Longitudinal maternal hemodynamics in pregnancies affected by fetal growth restriction

Correlation between maternal hemodynamic and sFlt-1/PlGF ratio in pregnancies affected by hypertensive disorders and fetal growth restriction

OBJECTIVES

Our aim was to investigate the correlation between maternal hemodynamic and sFlt1/PlGF ratio in different phenotypes of Hypertensive Disorders of Pregnancy and Fetal Growth Restriction.

STUDY DESIGN

We recruited high risk pregnancies for Hypertensive Disorders and Fetal Growth Restriction. Heart rate, cardiac output, total vascular resistance and myocardial wall relaxation were derived from transthoracic echocardiography. Doppler Velocimetry of uterine arteries and serum sFlt1/PlGF ratio were measured.

MAIN OUTCOMES MEASURES

The effect of maternal hemodynamic on the oxidative stress of the syncytiotrophoblast was proved by the significant correlation coefficient of the linear regression between sFlt-1/PlGF ratio with mean arterial pressure, heart rate, cardiac output, total vascular resistance, myocardial wall relaxation and uterine arteries' pulsatility index, which showed the highest correlation coefficient.

RESULTS

We identified 17 cases of Hypertensive Disorders of Pregnancy without Fetal Growth Restriction, 19 hypertensive patients with Fetal Growth Restriction, 25 cases of early Fetal Growth Restriction, 25 cases of late Fetal Growth Restriction and 16 controls. At univariate linear regression the sFlt-1/PlGF ratio significantly increased on average 85 times (+8549%) in case of hypertension associated with growth restriction, 17 times in case of isolated hypertension (+1681%), 6 times in early growth restriction (661%) and more than 5 times in the late form (542%). There was a correlation between sFlt-1/PlGF ratio and both uterine arteries' pulsatility index (ρ=0.48) and mean arterial pressure (ρ=0.45).

CONCLUSIONS

There is a significant relationship between maternal hemodynamic and sFlt-1/PlGF ratio, confirming the different characteristics of patients affected by hypertension and/or fetal growth restriction.

Maternal cardiovascular profile is altered in the preclinical phase of normotensive early and late intrauterine growth restriction

BACKGROUND

The maternal cardiovascular profile of patients who develop late fetal growth restriction has yet to be well characterized, however, a subclinical impairment in maternal hemodynamics and cardiac function may be present before pregnancy and may become evident because of the hemodynamic alterations associated with pregnancy.

OBJECTIVE

This study aimed to investigate if maternal hemodynamics and the cardiovascular profile might be different in the preclinical stages (22-24 weeks' gestation) in cases of early and late fetal growth restriction in normotensive patients.

STUDY DESIGN

This was a prospective echocardiographic study of 1152 normotensive nulliparous pregnant women at 22 to 24 weeks' gestation. The echocardiographic evaluation included morphologic parameters (left ventricular mass index and relative wall thickness, left atrial volume index) and systolic and diastolic maternal left ventricular function (ejection fraction, left ventricular global longitudinal strain, E/A ratio, and E/e' ratio). Patients were followed until the end of pregnancy to note the development of normotensive early or late fetal growth restriction.

RESULTS

Of the study cohort, 1049 patients had no complications, 73 were classified as having late fetal growth restriction, and 30 were classified as having early fetal growth restriction. In terms of left ventricular morphology, the left ventricular end-diastolic diameter was greater in uneventful pregnancies (4.84±0.28 cm) than in late (4.67±0.26 cm) and in early (4.55±0.26 cm) (P<.001) fetal growth restriction cases, whereas left ventricular end-systolic diameter was smaller in uneventful pregnancies (2.66±0.39 cm) than in late (2.83±0.40 cm) and in early (2.82±0.38 cm) (P<.001) fetal growth restriction cases. The relative wall thickness was slightly higher in early (0.34±0.05) and late (0.35±0.04) fetal growth restriction cases than in uneventful pregnancies (0.32±0.05) (P<.05). In terms of systolic left ventricular function, at 22 to 24 weeks' gestation, cardiac output was higher in uneventful pregnancies (6.58±1.07 L/min) than in late (5.40±0.97 L/min) and in early (4.76±1.05 L/min) (P<.001) fetal growth restriction cases with the lowest values in the early-onset group. Left ventricular global longitudinal strain was lower in appropriate for gestational age neonates (-21.6%±2.0%) and progressively higher in late (-20.1%±2.2%) and early (-18.5%±2.3%) (P<.001) fetal growth restriction cases. In terms of diastolic left ventricular function, the E/e' ratio showed intermediate values in the late fetal growth restriction group (7.90±2.73) when compared with the appropriate for gestational age group (7.24±2.43) and with the early fetal growth restriction group (10.76±3.25) (P<.001). The total peripheral vascular resistance was also intermediate in the late fetal growth restriction group (1300±199 dyne·s·cm-5) when compared with the appropriate for gestational age group (993±175 dyne·s·cm-5) and the early fetal growth restriction group (1488±255 dyne.s.cm-5) (P<.001).

CONCLUSION

Early and late fetal growth restriction share similar maternal hemodynamic and cardiovascular profiles with a different degree of expression. These features are already present at 22 to 24 weeks' gestation and are characterized by a hypodynamic state. The degree of these cardiovascular changes may influence the timing of the manifestation of the disease; a hypovolemic, high resistance, low cardiac output state might be associated with early-onset fetal growth restriction, whereas a milder hypovolemic state seems to favor the development of the disease in the final stages of pregnancy.

Use of a weight indexed umbilical artery systolic diastolic ratio to predict the risk for adverse outcomes among growth restricted fetuses

Background and Objectives: To evaluate weight-indexed umbilical systolic diastolic ratio (UASDR) to discriminate risk for adverse outcomes among growth restricted fetuses (FGR).Design and Setting: Retrospective study using prenatal ultrasound data and neonatal outcome data. Two primary outcomes: admission to intensive care and a composite outcome of severe neonatal morbidity. We included births among individuals with a singleton pregnancy at 24-40 weeks gestation without other indications for preterm delivery. We calculated the percentile of the measured standard UASDR, and the same value indexed to the EFW (iUASDR).Results: 296 pregnancies met inclusion criteria. Forty-seven percent required NICU admission and 31% developed a component of the composite outcome. The sensitivity of the iUASDR increased at lower birthweight percentiles. The positive predictive value of the standard UASDR was higher among fetuses with EFW <5th % and <10th % for NICU admission and composite outcome ((EFW <5th %) 0.82 (95% CI: 0.71, 0.91) and 0.60 (95% CI: 0.48, 0.72) and ((EFW <10th %) 0.81 (95% CI: 0.70, 0.89) and 0.58 (95% CI: 0.45, 0.69) compared with indexed values.Discussion: Data does not support use of the iUASDR to improve the test characteristics of the UASDR. Despite a moderate increase in specificity, the positive predictive value was low. UASDR non-indexed or standard values in conjunction with clinical findings and severity of FGR perform best.

Maternal vascular indices at 36 weeks' gestation in pregnancy with small or growth-restricted fetus

OBJECTIVE

To compare maternal vascular indices and hemodynamic parameters at 35-37 weeks' gestation in pregnancies complicated by delivery of a small-for-gestational-age (SGA) or growth-restricted (FGR) neonate.

METHODS

This was a prospective observational study of women with a singleton pregnancy attending for a routine hospital visit at 35 + 0 to 36 + 6 weeks' gestation. The visit included recording of maternal demographic characteristics, medical history, vascular indices and hemodynamic parameters, which were obtained using a non-invasive operator-independent device and included pulse-wave velocity, augmentation index, cardiac output, stroke volume, central systolic and diastolic blood pressure, total peripheral resistance and heart rate. Women with hypertensive disorders of pregnancy were excluded. SGA was diagnosed if birth weight was < 10th percentile. FGR was diagnosed if, in addition to birth weight < 10th percentile, at the 35-37-week scan, uterine artery or umbilical artery pulsatility index (PI) was > 95th percentile or fetal middle cerebral artery PI was < 5th percentile.

RESULTS

Among the 6413 women included in the study, there were 605 (9.4%) cases of SGA, 133 (2.1%) cases of FGR and 5675 (88.5%) cases that were unaffected by SGA or FGR. Women with SGA or FGR, compared to unaffected pregnancies, had increased peripheral vascular resistance and reduced cardiac output. Central systolic and diastolic blood pressure were increased in the FGR group compared with the unaffected group. Aortic stiffness, as assessed by pulse-wave velocity, and augmentation index did not differ between affected and unaffected pregnancies. In the FGR group, compared with the SGA group, central systolic and diastolic blood pressure were higher, whereas heart rate was lower.

CONCLUSIONS

SGA and FGR pregnancies exhibit deranged maternal hemodynamic responses compared with unaffected pregnancies. Pregnancies with FGR have higher central blood pressure compared to those with SGA, but it remains unclear whether these differences are driven by the size of the fetus or pathological fetal growth. © 2024 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal Hemodynamics from Preconception to Delivery: Research and Potential Diagnostic and Therapeutic Implications: Position Statement by Italian Association of Preeclampsia and Italian Society of Perinatal Medicine

OBJECTIVE

 The Italian Association of Preeclampsia (AIPE) and the Italian Society of Perinatal Medicine (SIMP) developed clinical questions on maternal hemodynamics state of the art.

STUDY DESIGN

 AIPE and SIMP experts were divided in small groups and were invited to propose an overview of the existing literature on specific topics related to the clinical questions proposed, developing, wherever possible, clinical and/or research recommendations based on available evidence, expert opinion, and clinical importance. Draft recommendations with a clinical rationale were submitted to 8th AIPE and SIMP Consensus Expert Panel for consideration and approval, with at least 75% agreement required for individual recommendations to be included in the final version.

RESULTS

 More and more evidence in literature underlines the relationship between maternal and fetal hemodynamics, as well as the relationship between maternal cardiovascular profile and fetal-maternal adverse outcomes such as fetal growth restriction and hypertensive disorders of pregnancy. Experts agreed on proposing a classification of pregnancy hypertension, complications, and cardiovascular states based on three different hemodynamic profiles depending on total peripheral vascular resistance values: hypodynamic (>1,300 dynes·s·cm-5), normo-dynamic, and hyperdynamic (<800 dynes·s·cm-5) circulation. This differentiation implies different therapeutical strategies, based drugs' characteristics, and maternal cardiovascular profile. Finally, the cardiovascular characteristics of the women may be useful for a rational approach to an appropriate follow-up, due to the increased cardiovascular risk later in life.

CONCLUSION

 Although the evidence might not be conclusive, given the lack of large randomized trials, maternal hemodynamics might have great importance in helping clinicians in understanding the pathophysiology and chose a rational treatment of patients with or at risk for pregnancy complications.

KEY POINTS

· Altered maternal hemodynamics is associated to fetal growth restriction.. · Altered maternal hemodynamics is associated to complicated hypertensive disorders of pregnancy.. · Maternal hemodynamics might help choosing a rational treatment during hypertensive disorders..

Resolvin D1 level during different trimesters of pregnancy for predicting the risk of fetal growth retardation in elderly pregnancy

Resolvin D1 (RvD1) is potentially associated with fetal growth retardation (FGR) through alleviating maternal inflammation and its linkage with several pregnancy complications. Thus, this study detected RvD1 levels at different trimesters of pregnancy, aiming to investigate its role in predicting FGR risk of elderly pregnant women. This prospective, observational cohort study enrolled 165 elderly pregnant women aged ≥35 years. Serum RvD1 was detected at 10-13 weeks (early pregnancy), 20-23 weeks (middle pregnancy), and 30-33 weeks (late pregnancy) of gestational week by enzyme-linked immunosorbent assay. RvD1 was varied among different trimesters of pregnancy in elderly pregnant women (p < 0.001). FGR occurred in 25 (15.2%) women in this study. RvD1 at early (p = 0.009), middle (p = 0.002), and late (p = 0.003) pregnancy was decreased in women with FGR versus those without. By multivariate analysis, RvD1 at middle pregnancy (odds ratio (OR): 0.477, p < 0.001), pre-pregnancy body mass index (OR: 0.763, p = 0.025), and gestational diabetes mellitus (yes versus no) (OR: 0.071, p = 0.031) were independently correlated with declined FGR risk. While age (OR: 1.382, p = 0.009) was independently associated with elevated risk of FGR. Furthermore, the combination of these independent factors as a predictive model exhibited a good potential for assessing FGR risk (area under the curve: 0.802, 95% confidence interval: 0.711-0.894). In conclusion, RvD1 at different trimesters of pregnancy is negatively linked with the risk of FGR, whose level at middle pregnancy serves as an independent factor for FGR risk in elderly pregnant women.

Reference ranges for third-trimester maternal cardiovascular function parameters measured in normotensive pregnant women using a non-invasive cardiac output monitor: A study based on data from the prospective PEACH cohort study

OBJECTIVE

We defined reference ranges for maternal cardiac output, systemic vascular resistance, and stroke volume measured in the third trimester of pregnancy using the Ultrasound Cardiac Output Monitor 1A.

DESIGN

Based on data from the prospective PEACH (PreEclampsia, Angiogenesis, Cardiac dysfunction and Hypertension) cohort study.

SETTING

Rigshospitalet and Hvidovre Hospital, Denmark.

SAMPLE

Normotensive pregnant women aged 18-45 years with singleton pregnancies, enrolled in the PEACH study in 2016-2018.

METHODS

We modelled cardiac output, systemic vascular resistance and stroke volume as a function of gestational age using multilevel linear models with fractional polynomials.

MAIN OUTCOME MEASURES

Unconditional and conditional reference ranges for cardiovascular parameters measured in gestational weeks 28-40.

RESULTS

Our study cohort included 405 healthy pregnant women who contributed 1210 cardiovascular function measurements for analysis. Maximum cardiac output and stroke volume values were measured in gestational weeks 30-32 and decreased over the third trimester, whereas systemic vascular resistance increased during the same period. We created reference ranges for eight combinations of maternal height, age and parity. We also created a simple calculator to allow for implementation of the reference ranges in clinical practice.

CONCLUSIONS

Our reference ranges allow the use of a bedside ultrasound device to non-invasively assess cardiac function in pregnancy and identify women at risk of complications. The unconditional ranges allow clinicians to evaluate isolated measurements and identify women needing follow-up. The conditional ranges incorporate information from previous measurements and improve monitoring over time.

The dilemma of sodium intake in preeclampsia: beneficial or detrimental?

Preeclampsia (PE) is a disorder involving de novo development of hypertension plus end organ damage after 20 weeks of gestation. PE is considered to be a heterogeneous disease. There are 2 main types of PE: early-onset (<34 weeks of gestation), which is considered to be a placental disorder and is associated with vasoconstriction, low cardiac output, and placental hypoperfusion and organ damage due to decreased microcirculation to maternal organs; and late-onset PE, which is primarily a disorder of pregnant women with obesity, diabetes, and/or cardiovascular abnormalities. In late-onset PE, there is avid sodium reabsorption by the maternal kidneys, causing hypervolemia and increased cardiac output, along with vasodilatation causing venous congestion of organs. Although PE has been a well-known disease for a long time, it is interesting to note that there is no specific sodium (salt) intake recommendation for these patients. This may be due to the fact that studies since as far back as the 1900s have shown conflicting results, and the reasons for the inconsistent findings have not been fully explained; furthermore, the type of PE in these studies was not specifically defined. Some studies suggest that sodium restriction may be detrimental in early-onset PE, but may be feasible in late-onset PE. To explore this paradox, the current review explains the hemodynamic factors involved in these 2 types of PE, summarizes the findings of the current studies, and highlights the knowledge gaps and the research needed to determine whether increase or restriction of salt or sodium intake is beneficial in different types of PE.

Sex differences in growth and mortality in pregnancy-associated hypertension

BACKGROUND

It is hypothesized that male fetuses prioritize growth, resulting in increased mortality, whereas females reduce growth in the presence of adversity. Preeclampsia reflects a chronic condition, in which fetuses have the opportunity to adjust growth. If females reduce their growth in response to preeclampsia, but males attempt to maintain growth at the cost of survival, we predict that differences in birthweight between preeclamptic and non-preeclamptic pregnancies will be greater among females, whereas differences in mortality will be greater among males.

METHODS

We analysed data from the Centers for Disease Control and Prevention. We compared pregnancies with pregnancy-associated hypertension (PAH) and controls.

RESULTS

The difference in birthweight between pregnancies affected by PAH and controls varied by fetal sex and gestational age. Among pregnancies of White individuals, at 34-35 weeks, the difference between PAH and controls was higher among females, as predicted. However, this pattern was reversed earlier in pregnancy and around term. Such variation was not significant in Black pregnancies. In both Black and White pregnancies, early in gestation, males had lower odds of death in PAH pregnancies, but higher odds of death in control pregnancies, counter to our prediction. Later, males had higher odds of death in PAH and controls, although the increased odds of death in males was not higher in PAH pregnancies than in controls. Overall, the difference in birthweight between surviving and non-surviving infants was greater in males than in females, opposite to our prediction.

CONCLUSIONS

The impact of PAH on birthweight and survival varies widely throughout gestation. Differences in birthweight and survival between male and female PAH and controls are generally not consistent with the hypothesis that males prioritize fetal growth more than females, and that this is a cause of increased mortality in males.

Feasibility of MRI assessment of maternal-fetal oxygen transport and consumption relative to maternal position in healthy late gestational pregnancies

Late gestational supine positioning reduces maternal cardiac output due to inferior vena caval (IVC) compression, despite increased collateral venous return. However, little is known about the impact of maternal position on oxygen (O2 ) delivery and consumption of the gravid uterus, fetus, placenta and lower limbs. We studied the effects of maternal positioning on these parameters in 20 healthy pregnant subjects at 36 ± 2 weeks using magnetic resonance imaging (MRI); a follow-up MRI was performed 6-months postpartum (n = 16/20). MRI techniques included phase-contrast and T1/T2 relaxometry for blood flow and oximetry imaging, respectively. O2 transport was measured in the following vessels (bilateral where appropriate): maternal abdominal descending aorta (DAoabdo ), IVC, ovarian, paraspinal veins (PSV), uterine artery (UtA) and external iliacs, and umbilical. Maternal cardiac output was measured by summing DAothoracic and superior vena cava flows. Supine mothers (n = 6) had lower cardiac output and O2 delivery in the DAoabdo , UtA and external iliac arteries, and higher PSV flow than those in either the left (n = 8) or right (n = 6) lateral positions during MRI. However, O2 consumption in the gravid uterus, fetus, placenta and lower limbs was unaffected by maternal positioning. The ratio of IVC/PSV flow decreased in supine mothers while ovarian venous flow and O2 saturation were unaltered, suggesting a major route of pelvic venous return unaffected by maternal position. Placental-fetal O2 transport and consumption were similar between left and right lateral maternal positions. In comparison to non-pregnant findings, DAoabdo and UtA O2 delivery and pelvic O2 consumption increased, while lower-limb consumption remained constant , despite reduced external iliac artery O2 delivery in late gestation. KEY POINTS: Though sleeping supine during the third trimester is associated with an increased risk of antepartum stillbirth, the underlying biological mechanisms are not fully understood. Maternal cardiac output and uteroplacental flow are reduced in supine mothers due to inferior vena caval compression from the weight of the gravid uterus. This MRI study provides a comprehensive circulatory assessment, demonstrating reduced maternal cardiac output and O2 delivery (uteroplacental, lower body) in supine compared to lateral positioning; however, O2 consumption (gravid uterus, fetus, placenta, lower limbs) was preserved. Unlike other mammalian species, the ovarian veins conduct substantial venous return from the human pregnant uterus that is unaffected by maternal positioning. Lumbar paraspinal venous flow increased in supine mothers. These observations may have important considerations during major pelvic surgery in pregnancy (i.e. placenta percreta). Future studies should address the importance of maternal positioning as a potential tool to deliver improved perinatal outcomes in pregnancies with compromised uteroplacental O2 delivery.

The Effects of Music-Based Interventions for Pain and Anxiety Management during Vaginal Labour and Caesarean Delivery: A Systematic Review and Narrative Synthesis of Randomised Controlled Trials

Music-based interventions are not physically invasive, they usually have minimal side effects, and they are increasingly being implemented during the birthing process for pain and anxiety relief. The aim of this systematic review is to summarise and evaluate published, randomised controlled trials (RCTs) assessing the effects of music-based interventions for pain and anxiety management during vaginal labour and caesarean delivery. Following the PRISMA guidelines, a systematic search of the literature was conducted using: PsychInfo (Ovid), PubMed, and Web of Science. Studies were included in the review if they were RCTs that assessed the effects of music on pain and anxiety during vaginal and caesarean delivery by human mothers. A narrative synthesis was conducted on 28 identified studies with a total of 2835 participants. Most, but not all, of the included studies assessing music-based interventions resulted in reduced anxiety and pain during vaginal and caesarean delivery. Music as part of a comprehensive treatment strategy, participant-selected music, music coupled with another therapy, and relaxing/instrumental music was specifically useful for reducing light to moderate pain and anxiety. Music-based interventions show promising effects in mitigating pain and anxiety in women during labour. However, the long-term effects of these interventions are unclear.

Maternal socioeconomic and lifestyle factors and life dissatisfaction associated with a small for gestational age infant. The Survey of Neonates in Pomerania (SNiP)

PURPOSE

The aim is to investigate the associations of the mother's socioeconomic and lifestyle factors and life satisfaction with the delivery of a small for gestational age (SGA) infant.

METHODS

Data from 4598 participants of the population-based birth cohort study Survey of Neonates in Pomerania (SniP) including comprehensive information on pregnancies, mothers, and their offspring in Western Pomerania, Germany were used in this study. The associations were analyzed using linear and logistic regression models.

RESULTS

After logistic regression analysis adjusted for height of the mother, women who delivered SGA infants, had lower education (p < 0.01) and smoked more frequently during pregnancy (p < 0.01) compared with mothers of adequate for gestational age (AGA) neonates. A mother with less than 10 years of education and one who continued smoking during pregnancy had an odds ratio (OR) of 2.23 [95% confidence interval (CI) = 1.44 to 3.46] and 2.68 (95% CI = 2.06-3.49) of having an SGA infant, respectively. There was no association between the employment of the mother (p = 0.28), the monthly income (p = 0.09), the family status (p = 0.80), the number of friendships outside the household that the mother would not wish to relinquish (p = 0.47), the number of people that she could rely on in case of an emergency (p = 0.75), or alcohol consumption prior to (p = 0.14) or during the pregnancy (p = 0.99) with SGA. Finally, women who delivered SGA infants were more frequently dissatisfied with their employment (p = 0.03) and financial status (p < 0.01).

CONCLUSIONS

Women who delivered SGA infants had more associated socioeconomic and lifestyle risk factors and were more frequently dissatisfied with their life conditions than mothers of AGA neonates.

A mathematical model of vascular and hemodynamics changes in early and late forms of preeclampsia

Preeclampsia-eclampsia syndrome is a leading cause of maternal mortality. The precise etiology of preeclampsia is still not well-defined and different forms exist, including early and late forms or preeclampsia, which may arise via distinctly different mechanisms. Low-dose aspirin administered at the end of the first trimester in women identified as high risk has been shown to reduce the incidence of early, but not late, preeclampsia; however, current risk factors show only fair predictive capability. There is a pressing need to develop accurate descriptions for the different forms of preeclampsia. This paper presents 1D fluid, solid, growth, and remodeling models for pregnancies complicated with early and late forms of preeclampsia. Simulations affirm a broad set of literature results that early forms of preeclampsia are characterized by elevated uterine artery pulsatility index (UA-PI) and total peripheral resistance (TPR) and lower cardiac output (CO), with modestly increased mean arterial blood pressure (MAP) in the first half of pregnancy, with elevation of TPR and MAP beginning at 20 weeks. Conversely, late forms of preeclampsia are characterized by only slightly elevated UA-PI and normal pre-term TPR, and slightly elevated MAP and CO throughout pregnancy, with increased TPR and MAP beginning after 34 weeks. Results suggest that preexisting arterial stiffness may be elevated in women that develop both early forms and late forms of preeclampsia; however, data that verify these results are lacking in the literature. Pulse wave velocity increases in early- and late-preeclampsia, coincident with increases in blood pressure; however, these increases are mainly due to the strain-stiffening response of larger arteries, rather than arterial remodeling-derived changes in material properties. These simulations affirm that early forms of preeclampsia may be associated with abnormal placentation, whereas late forms may be more closely associated with preexisting maternal cardiovascular factors; simulations also highlight several critical gaps in available data.

The cardiac-fetal-placental unit: fetal umbilical vein flow rate is linked to the maternal cardiac profile in fetal growth restriction

BACKGROUND

The functional maternal-fetal hemodynamic unit includes fetal umbilical vein flow and maternal peripheral vascular resistance.

OBJECTIVE

This study investigated the relationships between maternal and fetal hemodynamics in a population with suspected fetal growth restriction.

STUDY DESIGN

This was a prospective study of normotensive pregnancies referred to our outpatient clinic for a suspected fetal growth restriction. Maternal hemodynamics measurement was performed, using a noninvasive device (USCOM-1A) and a fetal ultrasound evaluation to assess fetal biometry and velocimetry Doppler parameters. Comparisons among groups were performed with 1-way analysis of variance with Student-Newman-Keuls correction for multiple comparisons and with Kruskal-Wallis test where appropriate. The Spearman rank coefficient was used to assess the correlation between maternal and fetal hemodynamics. Pregnancies were observed until delivery.

RESULTS

A total of 182 normotensive pregnancies were included. After the evaluation, 54 fetuses were classified as growth restricted, 42 as small for gestational age, and 86 as adequate for gestational age. The fetus with fetal growth restriction had significantly lower umbilical vein diameter (P<.0001), umbilical vein velocity (P=.02), umbilical vein flow (P<.0001), and umbilical vein flow corrected for fetal weight (P<.01) than adequate-for-gestational-age and small-for-gestational-age fetuses. The maternal hemodynamic profile in fetal growth restriction was characterized by elevated systemic vascular resistance and reduced cardiac output. The umbilical vein diameter was positively correlated to maternal cardiac output (r_s=0.261), whereas there was a negative correlation between maternal systemic vascular resistance (r_s=-0.338) and maternal potential energy-to-kinetic energy ratio (r_s=-0267). The fetal umbilical vein time averaged max velocity was positively correlated to maternal cardiac output (r_s=0.189) and maternal inotropy index (r_s=0.162), whereas there was a negative correlation with maternal systemic vascular resistance (r_s=-0.264) and maternal potential energy-to-kinetic energy ratio (r_s=-0.171). The fetal umbilical vein flow and the flow corrected for estimated fetal weight were positively correlated with maternal cardiac output (r_s=0.339 and r_s=0.297) and maternal inotropy index (r_s=0.217 and r=0.336), whereas there was a negative correlation between maternal systemic vascular resistance (r_s=-0.461 and r_s=-0.409) and maternal potential energy-to-kinetic energy ratio (r_s=-0.336 and r_s=-0.408).

CONCLUSION

Maternal and fetal hemodynamic parameters were different in the 3 groups of fetuses: fetal growth restriction, small for gestational age, and adequate for gestational age. Maternal hemodynamic parameters were closely and continuously correlated with fetal hemodynamic features. In particular, a maternal hemodynamic profile with high systemic vascular resistance, low cardiac output, reduced inotropism, and hypodynamic circulation was correlated with a reduced umbilical vein flow and increased umbilical artery pulsatility index. The mother, placenta, and fetus should be considered as a single cardiac-fetal-placental unit. The correlations of systemic vascular resistance, cardiac output, and inotropy index with umbilical artery impedance indicate the key role of these 3 parameters in placental vascular tree development. The umbilical vein flow rate and, therefore, the placental perfusion seems to be influenced not only by these three parameters but also by the maternal cardiovascular kinetic energy.

The effectiveness of auricular acupressure on pain management during labor: A systematic review and meta-analysis of randomized controlled trials

AIM

This meta-analysis aimed to systematically evaluate the effectiveness of auricular acupressure on pain management during labor.

METHODS

Six English and three Chinese electronic databases were comprehensively searched from inception to 6 November 2021. The PRISMA checklist was followed. The methodological quality of the included studies was assessed with the Cochrane Collaboration Bias Risk Assessment Tool. The meta-analysis was performed using Review Manager 5.3 software. Heterogeneity between studies was calculated using I² .

RESULTS

Five studies comprising 312 participants were included. The labor pain scores of the auricular acupressure group were significantly lower than those of the usual care group at cervix dilations of 6, 8, and 10 cm, with mean differences (95% confidence intervals) of -1.05 (-1.41, -0.69), -1.44 (-2.07, -0.82), and -1.96 (-3.30, -0.61), respectively. Auricular acupressure can thus effectively improve the labor pain perception at cervix dilations of 6, 8, and 10 cm. Moreover, auricular acupressure shortened the active phase, and had the trend of shortening the second and third stages of labor. There was no evidence that auricular acupressure had an effect on the rate of cesarean section or the 1 and 5 min Apgar scores.

CONCLUSION

Effective labor pain relief, better labor pain perception, and the lack of adverse effects support the use of auricular acupressure. More high-quality and rigorous trials are needed to verify our findings before we can make strong recommendations.

Association of exposure to per- and polyfluoroalkyl substances with hemoglobin and hematocrit during pregnancy

BACKGROUND

Per- and polyfluoroalkyl substances (PFASs) are common environmental contaminants and are widely detected in humans. Previous studies have linked PFASs exposure to adverse birth outcomes. However, the association between maternal exposure to PFASs and hemoglobin (Hb) and hematocrit (HCT) remains unclear.

OBJECTIVES

We aimed to explore the relationship between PFASs exposure with Hb and HCT during pregnancy.

METHODS

The present birth cohort study included 1044 pregnant women from Wuhan, China. Maternal HCT and Hb were measured in the first, second and third trimesters, and 13 PFASs were detected in the cord sera. Mixed linear models and general linear regression were applied to analyze the association between each single PFASs and Hb and HCT. Weighted quantile sum (WQS) regressions were used to investigate the association between PFASs mixture and Hb and HCT during pregnancy.

RESULTS

In single-PFAS models, 10 PFASs were positively associated with HCT and Hb across pregnancy (a 10-fold increase in PFASs was associated with 1.47-3.54 % change in HCT and 1.46-3.20 % change in Hb (All P-FDR < 0.05). In addition, Hb and HCT were more positively related to PFASs in the second and third trimesters rather than the first trimester. The association between PFASs exposure and maternal HCT and Hb was not significant in the iron supplementation group, whereas significant in the non-iron supplementation group. A significant interaction between iron supplementation and non-iron supplementation was also detected. WQS regressions showed that perfluorononanoic acid (PFNA) and perfluorohexane sulfonate (PFHxS) contributed most to the association between PFASs and HCT and Hb in the second and third trimesters, respectively.

CONCLUSION

Maternal PFASs exposure was positive with serum Hb and HCT. Moreover, maternal iron supplementation may play a modifying effect in influencing the relationship between PFASs and HCT and Hb.

Maternal cardiovascular function in the prediction of fetal distress in labor: a prospective cohort study

OBJECTIVE

To explore the strength of association and the diagnostic accuracy of maternal hemodynamic parameters detected noninvasively in predicting an adverse perinatal outcome in labor.

METHODS

Prospective cohort study of singleton women undergoing antepartum care at 37-39 weeks of gestation. A noninvasive ultrasonic cardiac output monitor (USCOM®) was used for cardiovascular assessment. The study outcome was a composite score of adverse perinatal outcome, which included at least one of the following variables: Cesarean or instrumental delivery for abnormal fetal heart monitoring, umbilical artery pH <7.10 or admission to neonatal special care unit. Attending clinicians were blinded to maternal cardiovascular indices. Multivariate logistic regression and area under the curve (AUC) analyses were used to test the diagnostic accuracy of different maternal and ultrasound characteristics in predicting adverse perinatal outcome.

RESULTS

A total of 133 women were recruited. The rate of adverse perinatal outcome was 25.6% (34/133). Women who delivered without abnormal perinatal outcome (controls) were more likely to be parous, compared to those who had an adverse perinatal outcome (44.4 vs. 73.5%; p = .005). Control women had significantly lower systemic vascular resistance (SVR) (median, 1166 vs. 1352 dynes × s/cm5, p = .023) and SVR index (SVRI) (median, 2168 vs. 2627 dynes × s/cm5/m2, p = .039) compared to women who had an adverse perinatal outcome. In this latter group the prevalence of SV <50 ml was significantly higher than in the control group (38.2% (13/34) vs. 11.1%, (11/99) p = .0012). At multivariable logistic regression analysis, SVR (aOR 1.307; 95% CI 1.112-2.23), SV <50 ml (aOR 4.70; 95% CI 1.336-12.006) and parity (3.90: 95% CI 1.545-10.334) were the only variables independently associated with adverse perinatal outcome. A model considering only SVR showed an AUC of 0.631. Integration of SVR with SV <50 ml and parity significantly improves the diagnostic performance of SVR alone to predict adverse outcome (AUC 0.732; p = .016).

CONCLUSION

Pre-labor modifications of maternal cardiovascular variables are associated with adverse perinatal outcome. However, their predictive accuracy for perinatal compromise is low, and thus their use as standalone screening test for adverse perinatal outcome in singleton pregnancies at term is not supported.

Is Maternal Cardiovascular Performance Impaired in Altitude-Associated Fetal Growth Restriction?

Mundo, William, Lilian Toledo-Jaldin, Alexandrea Heath-Freudenthal, Jaime Huayacho, Litzi Lazo-Vega, Alison Larrea-Alvarado, Valquiria Miranda-Garrido, Rodrigo Mizutani, Lorna G. Moore, Any Moreno-Aramayo, Richard Gomez, Patricio Gutierrez, and Colleen G. Julian. Is maternal cardiovascular performance impaired in altitude-associated fetal growth restriction? High Alt Med Biol. 23:352-360, 2022. Introduction: The incidence of fetal growth restriction (FGR) is elevated in high-altitude resident populations. This study aims to determine whether maternal central hemodynamics during the last trimester of pregnancy are altered in high-altitude FGR. Methods: In this cross-sectional study of maternal-infant pairs (FGR, n = 27; controls, n = 26) residing in La Paz, Bolivia, maternal heart rate, cardiac output (CO), stroke volume, and systemic vascular resistance (SVR) were assessed using continuous-wave Doppler ultrasound. Transabdominal Doppler ultrasound was used for uterine artery (UtA) resistance indices and fetal measures. Maternal venous soluble fms-like tyrosine kinase-1 (sFlt1) levels were measured. Results: FGR pregnancies had reduced CO, elevated SVR and UtA resistance, fetal brain sparing, and increased maternal sFlt1 versus controls. Maternal SVR was positively associated with UtA resistance and inversely associated with middle cerebral artery resistance and birth weight. Maternal sFlt1 was greater in FGR than controls and positively associated with UtA pulsatility index. Women with elevated sFlt1 levels also tended to have lower CO and higher SVR. Conclusion: Noninvasive assessment of maternal cardiovascular function may be an additional method for detecting high-risk pregnancies at high altitudes, thereby informing the need for increased surveillance and appropriate allocation of resources to minimize adverse outcomes.

Impact of maternal height, weight at presentation and gestational weight gain on cardiac adaptation in pregnancy

OBJECTIVE

To compare longitudinal maternal hemodynamic changes throughout gestation between different groups stratified according to weight at presentation and assess the relative influence of height, weight at presentation and gestational weight gain on cardiac adaptation.

METHODS

This was a prospective, longitudinal study assessing maternal hemodynamics using bioreactance technology at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. Women were divided into three groups according to maternal weight at presentation at the first visit at 11 + 0 to 13 + 6 weeks: Group 1, &lt; 60.0 kg (n = 421); Group 2, 60.0-79.7 kg (n = 904); Group 3, &gt; 79.7 kg (n = 427). A multilevel linear mixed-effects model was used to compare the repeated measures of hemodynamic variables, correcting for demographics, medical and obstetric history, pregnancy complications, maternal weight and time of evaluation. The linear mixed-effects model was then repeated using maternal height, weight at presentation and gestational weight gain Z-scores, and the standardized coefficients were used to evaluate the relative impact of each of these demographic parameters on longitudinal changes of maternal hemodynamics.

RESULTS

Compared with Group 1, women in Group 3 demonstrated higher cardiac output (CO), heart rate (HR) and mean arterial pressure (MAP) throughout pregnancy. Groups 2 and 3 had higher stroke volume (SV) than Group 1 at the first visit, but their SV plateaued between the first and second visits and demonstrated an earlier significant decrease from the second visit to the third visit when compared with Group 1. Compared with Groups 1 and 2, there was a higher prevalence of pre-eclampsia, gestational hypertension and gestational diabetes in Group 3. Maternal height was the most important contributor to CO, peripheral vascular resistance (PVR), SV and HR, while weight at presentation was the most important contributor to MAP. Gestational weight gain was the second most important characteristic influencing the longitudinal changes of PVR and SV.

CONCLUSIONS

Women with greater weight at presentation have a pathological hemodynamic profile, with higher CO, HR and MAP compared to women with lower weight at presentation. Height is the main determinant of CO, SV, HR and PVR, weight is the main determinant of MAP, and gestational weight gain is the second most important determinant of SV and PVR. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal hemodynamics and neonatal birth weight in pregnancies complicated by gestational diabetes: new insights from novel causal inference analysis modeling

OBJECTIVE

Normal pregnancy is characterized by significant changes in maternal hemodynamics that are associated with fetal growth. Pregnancies complicated by gestational diabetes mellitus (GDM) are associated with large-for-gestational age and macrosomia, but the relationship between maternal hemodynamic parameters and birth weight (BW) among women with GDM has not been established. Our objective was to investigate the influence of maternal hemodynamics on neonatal BW in healthy pregnancies and in those complicated by GDM.

METHODS

This was a prospective, cross-sectional case-control study of women aged ≥ 16 years with a singleton viable pregnancy, recruited between January 2016 and February 2021 at Leicester Royal Infirmary, Leicester, UK. GDM was defined as a fasting glucose level ≥ 5.3 mmol/L and/or serum glucose level ≥ 7.8 mmol/L, 2 h following a 75-g oral glucose load. We collected data on maternal characteristics and pregnancy outcome, including body mass index (BMI) at booking and BW centile adjusted for gestational age at delivery. Maternal hemodynamic parameters were assessed at 34-42 weeks' gestation using the Arteriograph® and bioreactance techniques. Graphical causal inference methodology was used to identify causal effects of the measured variables on neonatal BW centile.

RESULTS

Included in the analysis were 141 women with GDM and 136 normotensive non-diabetic pregnant controls. 62% of the women with GDM were managed pharmacologically, with metformin and/or insulin. Variables included in the final model were cardiac output (CO), mean arterial pressure (MAP), total peripheral resistance (TPR), aortic augmentation index (AIx), aortic pulse wave velocity (PWV) and BMI at booking. Among the controls, maternal BMI, CO and aortic PWV were significantly associated with neonatal BW. Each SD increase in booking BMI produced an increase of 8.4 BW centiles (P = 0.002), in CO produced an increase of 9.4 BW centiles (P = 0.008) and in aortic PWV produced an increase of 7.1 BW centiles (P = 0.017). We found no significant relationship between MAP, TPR or aortic AIx and neonatal BW. Maternal hemodynamics influenced neonatal BW among the women with GDM in a similar manner to that in the control group, but only the relationship between maternal BMI and neonatal BW reached statistical significance, with a 1-SD increase in BMI producing an increase of 6.1 BW centiles (P = 0.019).

CONCLUSIONS

Maternal BMI, CO and PWV were determinants of BW in our control group. The relationship between maternal hemodynamics and neonatal BW was similar between women with GDM and healthy controls. Our findings therefore suggest that fetal growth restriction in pregnancies complicated by GDM may indicate maternal cardiovascular dysfunction. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Maternal Low Volume Circulation Relates to Normotensive and Preeclamptic Fetal Growth Restriction

This narrative review summarizes current evidence on the association between maternal low volume circulation and poor fetal growth. Though much work has been devoted to the study of cardiac output and peripheral vascular resistance, a low intravascular volume may explain why high vascular resistance causes hypertension in women with preeclampsia (PE) that is associated with fetal growth restriction (FGR) and, at the same time, presents with normotension in FGR itself. Normotensive women with small for gestational age babies show normal gestational blood volume expansion superimposed upon a constitutionally low intravascular volume. Early onset preeclampsia (EPE; occurring before 32 weeks) is commonly associated with FGR, and poor plasma volume expandability may already be present before conception, thus preceding gestational volume expansion. Experimentally induced low plasma volume in rodents predisposes to poor fetal growth and interventions that enhance plasma volume expansion in FGR have shown beneficial effects on intrauterine fetal condition, prolongation of gestation and birth weight. This review makes the case for elevating the maternal intravascular volume with physical exercise with or without Nitric Oxide Donors in FGR and EPE, and evaluating its role as a potential target for prevention and/or management of these conditions.

Predictive role of Doppler indices of cerebral-placental-uterine ratio and umbilico-cerebral ratio for late-onset fetal growth restriction: a prospective cohort study

Predicting late-onset foetal growth restriction (FGR) has proven to be rather challenging. In this study, we propose a new parameter, cerebral-placental-uterine (CPU) ratio and umbilico-cerebral (UC) ratio for this matter. Results of this study which included a total of 227 nulliparous women showed that an increase in CPU ratio (OR = 0.45; 95% CI: 0.23-0.88; p=.020) was associated with lower odds of foetal weight above the 10th percentile at birth. CPU ratio measured at 35-37 weeks of gestation had an AUC of 0.78 (95% CI: 0.58, 0.98), sensitivity of 0.62 (95% CI: 0.24, 0.91) and specificity of 0.90 (95% CI: 0.79, 0.96) for prediction of late-onset FGR, which showed higher accuracy than UC ratio. As some cases of the late-onset FGR are not diagnosed by foetal biometry, it is important to find Doppler parameters that can help us predict these cases and CPU ratio may help physicians in detection of high-risk foetuses that will benefit from earlier intervention. Impact StatementWhat is already known on this subject? Late-onset foetal growth restriction (FGR) defined by an FGR diagnosis after 32 weeks of gestational age, can lead to short- and long-term morbidities and early diagnosis is the key to prevent these complications.What do the results of this study add? Results showed that each unit increase in numeric variables including CP ratio (OR = 0.29, p=.006), and CPU ratio (OR = 0.40, p=.006) was associated with lower odds of the foetal weight above the 10th percentile in the second ultrasound at 35-37 weeks. In other words, CPU ratio can prove to be useful marker in prediction of late-onset FGR.What are the implications of these findings for clinical practice and/or further research? Our prospective cohort study confirms the added value of low CPU ratio, with higher predictive accuracy than UC ratio, in predicting late-onset FGR. Detection of late FGR remains poor, but it is important to prevent stillbirth so further studies on the role of CPU ratio in predicting FGR and perinatal outcomes are needed.

Phenotype-Directed Management of Hypertension in Pregnancy

Hypertensive disorders of pregnancy are among the most serious conditions that pregnancy care providers face; however, little attention has been paid to the concept of tailoring clinical care to reduce associated adverse maternal and perinatal outcomes based on the underlying disease pathogenesis. This narrative review discusses the integration of phenotype-based clinical strategies in the management of high-risk pregnant patients that are currently not common clinical practice: real-time placental growth factor testing at Mount Sinai Hospital, Toronto and noninvasive hemodynamic monitoring to guide antihypertensive therapy at the University of Washington Medical Center, Seattle. Future work should focus on promoting more widespread integration of these novel strategies into obstetric care to improve outcomes of pregnancies at high risk of adverse maternal-fetal outcomes from these complications of pregnancy.

Association of N-Terminal Pro-Brain Natriuretic Peptide Concentration in Early Pregnancy With Development of Hypertensive Disorders of Pregnancy and Future Hypertension

IMPORTANCE

Hypertensive disorders of pregnancy are associated with future cardiovascular disease, perhaps because of subclinical cardiac dysfunction before pregnancy leading to impaired adaptation to pregnancy. Natriuretic peptides are promising biomarkers for detecting subclinical cardiac dysfunction outside of pregnancy.

OBJECTIVE

To investigate whether higher concentrations of N-terminal pro-brain natriuretic peptide (NT-proBNP) in early pregnancy would be associated with hypertensive disorders of pregnancy and hypertension 2 to 7 years post partum.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used data from the The Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-Be Heart Health Study, a prospective multicenter observational study. A total of 4103 nulliparous women with complete data and no prepregnancy hypertension or diabetes who were treated at 8 clinical sites were included. Women were followed up with for 2 to 7 years after pregnancy. Data were collected from October 2010 to October 2017, and data were analyzed from August 2020 to November 2021.

EXPOSURES

NT-proBNP concentration, measured using an electrochemiluminescence immunoassay from a first-trimester blood sample.

MAIN OUTCOMES AND MEASURES

Hypertensive disorders of pregnancy and incident hypertension (systolic blood pressure of 130 mm Hg or diastolic blood pressure of 80 mm Hg or use of antihypertensive agents) at follow-up visit.

RESULTS

A total of 4103 women met inclusion criteria; the mean (SD) age was 27.0 (5.6) years. Among these women, 909 (22.2%) had an adverse pregnancy outcome, and 817 (19.9%) had hypertension at the follow-up visit. Higher NT-proBNP concentrations were associated with a lower risk of hypertensive disorders of pregnancy (adjusted odds ratio per doubling, 0.81; 95% CI, 0.73-0.91), which persisted after adjustment for age, self-reported race and ethnicity, early-pregnancy body mass index, smoking, and aspirin use. Similarly, higher NT-proBNP concentration in early pregnancy was also associated with a lower risk of incident hypertension 2 to 7 years after delivery (adjusted odds ratio per doubling, 0.84; 95% CI, 0.77-0.93), an association that persisted after controlling for confounders, including hypertensive disorders of pregnancy.

CONCLUSIONS AND RELEVANCE

In this cohort study, higher NT-proBNP concentrations in early pregnancy were associated with a lower risk of hypertensive disorders of pregnancy and hypertension 2 to 7 years post partum. These findings suggest that normal early-pregnancy cardiovascular physiology, as assessed by NT-proBNP concentration, may provide biologic insights into both pregnancy outcome and cardiovascular disease risk.

Fetal Growth Restriction: Does an Integrated Maternal Hemodynamic-Placental Model Fit Better?

In recent years, a growing interest has arisen regarding the possible relationship between adverse pregnancy outcomes (APOs) and inadequate maternal hemodynamic adaptations to the pregnancy. A possible association between "placental syndromes," such as preeclampsia (PE) and fetal growth restriction (FGR), and subsequent maternal cardiovascular diseases (CVD) later in life has been reported. The two subtypes of FGR show different pathogenetic and clinical features. Defective placentation, due to a poor trophoblastic invasion of the maternal spiral arteries, is believed to play a central role in the pathogenesis of early-onset PE and FGR. Since placental functioning is dependent on the maternal cardiovascular system, a pre-existent or subsequent cardiovascular impairment may play a key role in the pathogenesis of early-onset FGR. Late FGR does not seem to be determined by a primary abnormal placentation in the first trimester. The pathological pathway of late-onset FGR may be due to a primary maternal cardiovascular maladaptation: CV system shows a flat profile and remains similar to those of non-pregnant women. Since the second trimester, when the placenta is already developed and increases its functional request, a hypovolemic state could lead to placental hypoperfusion and to an altered maturation of the placental villous tree and therefore to an altered fetal growth. Thus, this review focalizes on the possible relationship between maternal cardiac function and placentation in the development of both early and late-onset FGR. A better understanding of maternal hemodynamics in pregnancies complicated by FGR could bring various benefits in clinical practice, improving screening and therapeutic tools.

Effect of maternal age on cardiac adaptation in pregnancy

OBJECTIVE

To compare longitudinal maternal hemodynamic changes throughout gestation between different age groups.

METHODS

This was a prospective longitudinal study assessing maternal hemodynamics using a bioreactance technique at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. Women were divided into four groups according to maternal age at the first visit at 11 + 0 to 13 + 6 weeks: Group 1, < 25.0 years; Group 2, 25.0-30.0 years; Group 3, 30.1-34.9 years; and Group 4, ≥ 35.0 years. A multilevel linear mixed-effects model was performed to compare the repeat measurements of hemodynamic variables, correcting for demographics, medical and obstetric history, pregnancy complications, maternal age and gestational-age window.

RESULTS

The study population included 254 women in Group 1, 442 in Group 2, 618 in Group 3 and 475 in Group 4. Younger women (Group 1) had the highest cardiac output (CO) and lowest peripheral vascular resistance (PVR), and older women (Group 4) had the lowest CO and highest PVR throughout pregnancy. The higher CO seen in younger women was achieved through an increase in heart rate alone and not with a concomitant rise in stroke volume. Although the youngest age group demonstrated an apparently more favorable hemodynamic profile, it had the highest incidence of a small-for-gestational-age neonate. There was no significant difference between the groups in the incidence of pre-eclampsia.

CONCLUSION

Age-specific differences in maternal hemodynamic adaptation do not explain the differences in the incidence of a small-for-gestational-age neonate between age groups. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

Maternal and Fetal Hemodynamic Adaptations to Pregnancy and Clinical Outcomes in Maternal Cardiac Disease

BACKGROUND

Although insufficient maternal cardiac output (CO) has been implicated in poor outcomes in mothers with heart disease (HD), maternal-fetal interactions remain incompletely understood. We sought to quantify maternal-fetal hemodynamics using magnetic resonance imaging (MRI) and explore their relationships with adverse events.

METHODS

Pregnant women with moderate or severe HD (n=22; age 32±5 years) were compared with healthy controls (n=21; 34±3 years). An MRI was performed during the third trimester at peak output (maternal-fetal) and six-months postpartum with return of maternal hemodynamics to baseline (reference). Phase-contrast MRI was used for flow quantification and was combined with T1/T2 relaxometry for derivation of fetal oxygen delivery/consumption.

RESULTS

 Third trimester CO and cardiac index (CI) measurements were similar in HD and control groups (CO 7.2±1.5 versus 7.3±1.6 L/min, p=0.79; CI 4.0±0.7 versus 4.3±0.7 L/min/m², p=0.28). However, the magnitude of CO/CI increase (Δ, peak-pregnancy-reference) in the HD group exceeded controls (CO 46±24% versus 27±16%, p=0.007; CI 51±28% versus 28±17%, p=0.005). Fetal growth and oxygen delivery/consumption were similar between groups. Adverse cardiovascular outcomes (non-mutually exclusive) in 6 HD women included arrhythmia (n=4), heart failure (n=2) and hypertensive disorder of pregnancy (n=1); fetal prematurity was observed in 2 of these women. The odds of a maternal cardiovascular event were inversely associated with peak CI (OR 0.10 [95% confidence interval 0.001-0.86], p=0.04) and ΔCI (0.02 [0.001-0.71], p=0.03).

CONCLUSIONS

 Maternal-fetal hemodynamics can be well-characterized in pregnancy using MRI. Impaired adaptation to pregnancy in women with HD appears to be associated with development of adverse outcomes of pregnancy.

BRIEF SUMMARY

Maternal and placental-fetal vascular flows in women with heart disease (HD) were measured using magnetic resonance imaging. Adaptive peak pregnancy cardiac output and cardiac index (CI) were formidable in the majority of mothers. Placental-fetal hemodynamics were maintained and neonatal outcomes were favourable. Women with adverse cardiovascular events in pregnancy had insufficient augmentation of CI antenatally. Understanding hemodynamic responses of HD mothers in pregnancy may help physicians counsel women pre-conceptually and further optimize management antenatally.

The cardio-ankle vascular index as a predictor of adverse pregnancy outcomes

OBJECTIVE

To assess the association between maternal hemodynamic parameters; cardio-ankle vascular index (CAVI), representing arterial stiffness; mean arterial pressure (MAP), uterine artery pulsatility index (Ut-PI), and adverse pregnancy outcomes including preeclampsia (PE), fetal growth restriction (FGR), and gestational diabetes mellitus (GDM).

METHODS

A prospective cohort study was conducted on low-risk pregnancies. All were serially measured for the mean CAVI, MAP, and Ut-PI for four times at gestational age (GA) 11-14, 18-22, 28-32, and after 36 weeks. Also, the women were followed up for pregnancy outcomes, focusing on PE, FGR, and GDM.

RESULTS

Of 335 recruited cases meeting the inclusion criteria, 16 cases developed PE, 24 cases had FGR, and 83 cases had GDM. Compared to the non-PE group, women developing PE had a significant increase in CAVI at 18-22, 28-32, and after 36 weeks (P-value = 0.021, 0.003, and <0.001, respectively), a significant increase in MAP at all of the four periods (P-value < 0.001, for all periods), and a significant increase in Ut-PI during GA 18-22 weeks (P-value = 0.021). In pregnancies with FGR, there was a significant increase of CAVI at GA 18-22, 28-32 and after 36 weeks (P-value = 0.012, 0.015, and 0.004, respectively), an increase in Ut-PI in all gestational periods (P-value < 0.05) but no changes of MAP throughout pregnancy. In GDM, the three parameters were not significantly different from those in the non-GDM group in all of the four periods. CAVI could predict PE and FGR with AUC of 0.655-0.835 and 0.673-0.760, respectively. CAVI added predictive values when combined with MAP or Ut-PI.

CONCLUSION

Increased CAVI, like MAP and Ut-PI, can be used as a predictor of PE and FGR but not GDM. Also, it has an added predictive value when combined with MAP or Ut-PI.

Maternal cardiac adaptation and fetal growth

BACKGROUND

Pregnancies with small-for-gestational-age fetuses are at increased risk of adverse maternal-fetal outcomes. Previous studies examining the relationship between maternal hemodynamics and fetal growth were mainly focused on high-risk pregnancies and those with fetuses with extreme birthweights, such as less than the 3rd or 10th percentile and assumed a similar growth pattern in fetuses above the 10th percentile throughout gestation.

OBJECTIVE

This study aimed to evaluate the trends in maternal cardiac function, fetal growth, and oxygenation with advancing gestational age in a routine obstetrical population and all ranges of birthweight percentiles.

STUDY DESIGN

This was a prospective, longitudinal study assessing maternal cardiac output and peripheral vascular resistance by bioreactance at 11⁺⁰ to 13⁺⁶, 19⁺⁰ to 24⁺⁰, 30⁺⁰ to 34⁺⁰, and 35⁺⁰ to 37⁺⁰ weeks' gestation, sonographic estimated fetal weight in the last 3 visits and the ratio of the middle cerebral artery by umbilical artery pulsatility indices or cerebroplacental ratio in the last 2 visits. Women were divided into the following 5 groups according to birthweight percentile: group 1, <10th percentile (n=261); group 2, 10 to 19.9 percentile (n=180); group 3, 20 to 29.9 percentile (n=189); group 4, 30 to 69.9 percentile (n=651); and group 5, ≥70th percentile (n=508). The multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables and z scores of the estimated fetal weight and cerebroplacental ratio.

RESULTS

In visit 2, compared with visit 1, in all groups, cardiac output increased, and peripheral vascular resistance decreased. At visit 3, groups 1, 2, and 3, compared with 4 and 5, demonstrated an abrupt decrease in cardiac output and increase in peripheral vascular resistance. From visit 2, group 1 had a constant decline in estimated fetal weight, coinciding with the steepest decline in maternal cardiac output and rise in peripheral vascular resistance. In contrast, in groups 4 and 5, the estimated fetal weight had a stable or accelerative pattern, coinciding with the greatest increase in cardiac output and lowest peripheral vascular resistance. Groups 2 and 3 showed a stable growth pattern with intermediate cardiac output and peripheral vascular resistance. Increasing birthweight was associated with higher cerebroplacental ratio. Groups 3, 4, and 5 had stable cerebroplacental ratio across visits 3 and 4, whereas groups 1 and 2 demonstrated a significant decline (P<.001).

CONCLUSION

In a general obstetrical population, maternal cardiac adaptation at 32 weeks' gestation parallels the pattern of fetal growth and oxygenation; babies with birthweight<20th percentile have progressive decline in fetal cerebroplacental ratio, decline in maternal cardiac output, and increase in peripheral vascular resistance.

Pro- and Anti-Angiogenic Markers as Clinical Tools for Suspected Preeclampsia with and without FGR near Delivery—A Secondary Analysis

Objective—the objective of this study was to assess the accuracy of placental growth factor (PlGF), soluble Fms-like Tyrosine Kinase 1 (sFlt-1), and endoglin (sEng) in the diagnosis of suspected preeclampsia (PE) with and without fetal growth restriction (FGR) near delivery. Methods—this is a secondary analysis of a dataset of 125 pregnant women presenting at the high risk pregnancy clinic with suspected PE, FGR or PE + FGR in the University Medical Center of Slovenia. The dataset included 31 PE cases, 16 FGR cases, 42 PE + FGR cases, 15 cases who developed with unrelated complications before 37 weeks (wks) (PTD), and 21 unaffected controls who delivered a healthy baby at term. We also analyzed a sub-group of women who delivered early (<34 wks) including 10 PE, 12 FGR, 28 PE + FGR, and six PTD. Clinical management adhered to hospital guidelines. Marker levels were extracted from the dataset and were used to develop Receiver Operating Characteristic (ROC) curves and to calculate the area under the curve (AUC), the detection rates (DRs), and the false positive rates (FPRs). Previously published marker cutoffs for yes/no admission to hospital wards were extracted from the literature. Negative and positive predictive values (NPVs and PPVs) were evaluated for their value in determining whether hospital admission was required. Non-parametric tests were applied for statistical analysis; p < 0.05 was considered significant. Results—near delivery, all the pro-and anti-angiogenic markers provided diagnostic (ROC = 1.00) accuracy for the early (<34 wks) group of FGR. Diagnostic or near diagnostic (ROC = 0.95) accuracy was achieved by all marker for early PE + FGR but lower accuracy was achieved for early PE. For all cases, all markers, especially PlGF reached diagnostic or near diagnostic accuracy for FGR and PE + FGR. At this accuracy level, they can contribute to the clinical management of FGR, and PE + FGR. All the markers were less accurate for all PE cases. The use of published cutoffs was adequate for clinical management of FGR, whether early or for all cases, using an NPV > 90%. For PE + FGR, the PPV value approached 100%, especially for early cases, and can thus be implemented in clinical management. Neither NPV nor PPV were high enough for managing all cases of PE. There was no added value in measuring the PlGF/(sFlt-1 + sEng) ratio. Conclusion—This is the first study on a Slovenian population. It shows that near-delivery angiogenic biomarkers tests may be useful for confirming the diseases in cases where there is a diagnostic doubt. However, the clinical use of the biomarkers needs to be weighed against resources available and degree of certainty of the diagnosis made with and without them for managing suspected FGR and PE + FGR requiring delivery <34 wks, where they are very accurate, and furthermore in the management of all cases of FGR and FGR+PE. The markers were less accurate for the clinical diagnosis of PE.

Intrapartum Doppler ultrasound: where are we now?

Intrapartum hypoxic events most commonly occur in low-risk pregnancies with appropriately grown fetuses. Continuous intrapartum monitoring by means of cardiotocography has not demonstrated a reduction in the frequency of adverse perinatal outcome but has been linked with an increase in the caesarean section rate, particularly among women considered at low risk. Available data from the literature suggests that abnormalities in the uterine artery Doppler and in the ratio between fetal cerebral and umbilical Doppler (i.e. cerebroplacental ratio [CPR]) are associated with conditions of subclinical placental function occurring in fetuses who have failed to achieve their growth potential regardless of their actual size. In this review we summarize the available evidence on the use of intrapartum Doppler ultrasound for the fetal surveillance during labor and the identification of the fetuses at risk of intrapartum distress.

Oxidative Stress and Neurodevelopmental Outcomes in Rat Offspring with Intrauterine Growth Restriction Induced by Reduced Uterine Perfusion

Intrauterine growth restriction (IUGR) is a major cause of morbidity and mortality and is worldwide associated with delayed neurodevelopment. The exact mechanism involved in delayed neurodevelopment associated with IUGR is still unclear. Reduced uterine perfusion (RUP) is among the main causes of placental insufficiency leading to IUGR, which is associated with increases in oxidative stress. This study investigated whether oxidative stress is associated with delayed neurodevelopment in IUGR rat pups. Pregnant rats were exposed to RUP surgery on gestational day 14 to generate IUGR rat offspring. We evaluated offspring’s morphometric at birth, and neurodevelopment on postnatal day 21 (PD21) as well as markers of oxidative stress in plasma and brain. Offspring from dams exposed to RUP showed significant (p < 0.05) lower birth weight compared to controls, indicating IUGR. Motor and cognitive deficits, and levels of oxidative stress markers, were significantly (p < 0.05) elevated in IUGR offspring compared to controls. IUGR offspring showed significant (p < 0.05) negative correlations between brain lipid peroxidation and neurocognitive tests (open field and novel object recognition) in comparison with controls. Our findings suggest that neurodevelopmental delay observed in IUGR rat offspring is associated with increased levels of oxidative stress markers.

Hemodynamic Complications in Pregnancy: Preeclampsia and Beyond

Normal pregnancy is a complex and dynamic process that requires significant adaptation from the maternal system. Failure of this adaptive process in pregnancy contributes to many pregnancy related disorders, including the hypertensive disorders of pregnancy. This article discusses placental development and how abnormalities in the process of vascular remodeling contribute to the multisystem maternal and fetal disease that is preeclampsia and fetal growth restriction. We review some of the consequences of this condition on the mother and fetus, aspects of the clinical management of preeclampsia and how it can influence both mother and infant in the postnatal period and beyond.

Effect of race on longitudinal central hemodynamics in pregnancy

OBJECTIVE

To compare central hemodynamics between white, black and Asian women in pregnancy.

METHODS

This was a prospective, longitudinal study of maternal central hemodynamics in white, black and Asian women with a singleton pregnancy, assessed using a bioreactance method at 11 + 0 to 13 + 6, 19 + 0 to 24 + 0, 30 + 0 to 34 + 0 and 35 + 0 to 37 + 0 weeks' gestation. At each visit, cardiac output (CO), stroke volume (SV), heart rate (HR), peripheral vascular resistance (PVR) and mean arterial pressure were recorded. Multilevel linear mixed-effects analysis was performed to compare the repeated measures of the cardiac variables between white, black and Asian women, controlling for maternal characteristics, medical history and medication use.

RESULTS

The study population included 1165 white, 247 black and 116 Asian women. CO increased with gestational age to a peak at 32 weeks and then decreased; the highest CO was observed in white women and the lowest in Asian women. SV initially increased after the first visit but subsequently declined with gestational age in white women, decreased with gestational age in black women and remained static in Asian women. In all three study groups, HR increased with gestational age until 32 weeks and then remained constant; HR was highest in black women and lowest in white women. PVR showed a reversed pattern to that of CO; the highest values were in Asian women and the lowest in white women. The least favorable hemodynamic profile, which was observed in black and Asian women, was reflected in higher rates of a small-for-gestational-age infant.

CONCLUSIONS

There are race-specific differences in maternal cardiac adaptation to pregnancy. White women have the most favorable cardiac adaptation by increasing SV and HR, achieving the highest CO and lowest PVR. In contrast, black and Asian women have lower CO and higher PVR than do white women, with CO increasing through a rise in HR due to declining or static SV. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Placental function and fetal weight are associated with maternal hemodynamic indices in uncomplicated pregnancies at 35-37 weeks of gestation

BACKGROUND

Over the years, there has been an increasing interest in the assessment of maternal hemodynamic responses during pregnancy. With the use of both noninvasive devices and/or maternal echocardiography, it has been shown that mothers who have pregnancy complications have altered hemodynamics compared with those who have uncomplicated pregnancies. It also has been suggested that preexisting maternal cardiac changes might drive the development of complications in pregnancy that are associated with impaired placentation. To understand, however, this potential link in complicated pregnancies, it is important to clarify whether placental function is associated with maternal cardiac functional indices in normal pregnancies.

OBJECTIVE

To determine whether placental function, perfusion, and fetal weight are associated with maternal cardiac hemodynamic responses at 35-36 weeks of gestation in normal pregnancies.

STUDY DESIGN

Prospective screening of women attending Kings' College Hospital for routine hospital visit at 35-37 weeks' gestation. We recorded maternal characteristics and measured mean arterial pressure, uterine artery pulsatility index, sonographic estimated fetal weight, and serum placental growth factor and soluble fms-like tyrosine kinase 1. We also performed maternal echocardiogram to assess cardiac output and peripheral vascular resistance as well as indices of diastolic and systolic function, including global longitudinal systolic function and left ventricular mass indexed to body surface area.

RESULTS

We studied 1386 women. Maternal characteristics were associated with both maternal hemodynamics and functional and structural indices. Uterine artery pulsatility index was associated with left ventricular mass (P=.03) and global longitudinal systolic function (P=.017). There were significant nonlinear associations between placental growth factor and cardiac output and peripheral vascular resistance (P<.001 for both) and between soluble fms-like tyrosine kinase 1 and peripheral vascular resistance (P=.018). Estimated fetal weight was associated with maternal cardiac output (mean increase=0.186, 95% confidence interval, 0.133-0.238, P<.001) and peripheral vascular resistance (mean decrease=-0.164, 95% confidence interval, -0.217 to -0.111, P<.001). No association was noted between placental and fetal parameters and maternal cardiac functional and structural indices. In multivariable analysis, placental growth factor remained strongly associated with maternal cardiac output and peripheral vascular resistance (P=.002 for both) over and above maternal characteristics and estimated fetal weight. Estimated fetal weight was associated with left ventricular mass (0.102, 95% confidence interval, 0.044-0.162, P=.001).

CONCLUSION

The results of this study suggest a strong link between maternal hemodynamic responses and fetoplacental needs across the whole spectrum in normal pregnancies. These findings would also indicate that to diagnose maternal cardiac dysfunction in pregnancies complicated by impaired placentation a more extensive echocardiographic assessment might be needed rather than relying on hemodynamics which are strongly associated with fetoplacental indices.

Clinical validation of bioreactance for the measurement of cardiac output in pregnancy

Maternal cardiac dysfunction is associated with pre-eclampsia, fetal growth restriction and haemodynamic instability during obstetric anaesthesia. There is growing interest in the use of non-invasive cardiac output monitoring to guide antihypertensive and fluid therapies in obstetrics. The aim of this study was to validate thoracic bioreactance using the NICOM® instrument against transthoracic echocardiography in pregnant women, and to assess the effects of maternal characteristics on the absolute difference of stroke volume, cardiac output and heart rate. We performed a prospective study involving women with singleton pregnancies in each trimester. We recruited 56 women who were between 11 and 14 weeks gestation, 57 between 20 and 23 weeks, and 53 between 35 and 37 weeks. Cardiac output was assessed repeatedly and simultaneously over 5 min in the left lateral position with NICOM and echocardiography. The performance of NICOM was assessed by calculating bias, 95% limits of agreement and mean percentage difference relative to echocardiography. Multivariate regression analysis evaluated the effect of maternal characteristics on the absolute difference between echocardiography and NICOM. The mean percentage difference of cardiac output measurements between the two methods was ±17%, with mean bias of -0.13 l.min^-1 and limits of agreement of -1.1 to 0.84; stroke volume measurements had a mean percentage difference of ±15%, with a mean bias of -0.8 ml (-10.9 to 12.6); and heart rate measurements had a mean percentage difference of ±6%, with a mean bias of -2.4 beats.min^-1 (-6.9 to 2.0). Similar results were found when the analyses were confined to each individual trimester. The absolute difference between NICOM and echocardiography was not affected by maternal age, weight, height, race, systolic or diastolic blood pressure. In conclusion, NICOM demonstrated good agreement with echocardiography, and can be used in pregnancy for the measurement of cardiac function.

Maternal cardiac function in women at high risk for pre-eclampsia treated with 150 mg aspirin or placebo: an observational study

OBJECTIVE

To compare maternal haemodynamics in women at low and high risk for preterm pre-eclampsia (PE), and between those at high risk who are randomised to aspirin or placebo.

DESIGN

Prospective, longitudinal observational study.

SETTING

Maternity units in six UK hospitals.

POPULATION

Women participating in the Aspirin for Prevention of Preterm Pre-eclampsia (ASPRE) trial. The population comprised three groups of women: low risk for preterm PE (n = 1362), high risk for preterm PE treated with aspirin (n = 208) and high risk for preterm PE on placebo (n = 220).

METHODS

Women had four visits during pregnancy: 11-14, 19-24, 30-34, and 35-37 weeks' gestation. Blood pressure was measured with a device validated for pregnancy, and PE and maternal haemodynamics were assessed with a bioreactance monitor at each visit. A multilevel linear mixed-effects analysis was performed to examine longitudinal changes of maternal haemodynamic variables, controlling for demographic characteristics, past medical history and medication use.

MAIN OUTCOME MEASURES

Longitudinal changes of cardiac output (CO), mean arterial pressure (MAP), and peripheral vascular resistance (PVR).

RESULTS

The low-risk group demonstrated the expected changes with an increase in CO and reduction in MAP and PVR, with a quadratic change across gestation. In contrast, the high-risk groups had a declining CO, and higher MAP and PVR during pregnancy. The administration of aspirin did not appear to affect maternal haemodynamics.

CONCLUSIONS

Women screened as high risk for preterm PE have a pathological cardiac adaptation to pregnancy and the prophylactic use of aspirin (150 mg oral daily from the first trimester) in this group may not alter this haemodynamic profile.

TWEETABLE ABSTRACT

In women at high risk of pre-eclampsia, prophylactic use of aspirin may not alter the impaired maternal cardiac adaptation.

Are maternal hemodynamic indices markers of fetal growth restriction in pregnancies with a small-for-gestational-age fetus?

OBJECTIVE

Pregnancies complicated by fetal growth restriction (FGR) have a worse outcome than those with a small-for-gestational-age (SGA) fetus. There is increasing evidence of a maternal cardiovascular role in the pathophysiology of FGR. We aimed to compare maternal hemodynamic indices between pregnancies complicated by FGR and those delivering a SGA neonate, using a non-invasive device.

METHODS

This was a prospective study of normotensive pregnancies complicated by FGR (defined as estimated fetal weight (EFW) < 3^rd centile or Doppler evidence of impaired placental-fetal blood flow), those with a SGA fetus (defined as EFW < 10^th centile) and control pregnancies with an appropriately grown fetus. Assessment of maternal hemodynamics (heart rate (HR), cardiac output (CO), mean arterial pressure (MAP), systemic vascular resistance (SVR) and stroke volume) was performed using a non-invasive device (USCOM-1A®). Uterine artery (UtA) pulsatility index (PI) was measured using transabdominal ultrasound. Hemodynamic variables that are affected by gestational age and maternal characteristics were corrected for using device-specific reference ranges. Comparison between groups was performed using the chi-square test or the Mann-Whitney U-test, as appropriate.

RESULTS

A total of 102 FGR, 64 SGA and 401 control pregnancies, with a median gestational age of 36 weeks, were included in the analysis. Women with a pregnancy complicated by FGR and those with a SGA fetus were shorter and weighed less than did controls. Compared with controls, the FGR group had significantly lower median maternal HR (80 beats per min (bpm) vs 85 bpm; P = 0.001) and CO multiples of the median (MoM; 0.91 vs 0.98; P = 0.003), and higher median maternal MAP (90 mmHg vs 87 mmHg; P = 0.040), SVR MoM (1.2 vs 1.0; P < 0.001) and UtA-PI MoM (1.1 vs 0.96; P < 0.001), but there was no significant difference in stroke volume MoM (1.0 vs 0.98; P = 0.647). Compared with the SGA group, the FGR group had a significantly lower median HR (80 bpm vs 87 bpm; P = 0.022), and higher median maternal MAP (90 mmHg vs 85 mmHg; P = 0.025), SVR MoM (1.2 vs 1.0; P = 0.002) and UtA-PI MoM (1.1 vs 0.98; P = 0.005), but there was no significant difference in CO MoM (0.91 vs 0.96; P = 0.092) or stroke volume MoM (1.0 vs 1.0; P = 0.806). There were no significant differences in adjusted maternal hemodynamic indices between the SGA group and controls.

CONCLUSION

Pregnancies complicated by FGR presented with impaired maternal hemodynamic function, as evidenced by lower HR and CO, as well as higher MAP, SVR and UtA resistance. Pregnancies delivering a SGA neonate, without evidence of FGR, had normal maternal hemodynamic function. Maternal hemodynamic indices may therefore be of value in distinguishing FGR from SGA pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

Central hemodynamics are associated with fetal outcomes in pregnancies of advanced maternal age

OBJECTIVES

Age is a known risk factor for both maternal cardiovascular disease and adverse outcomes in pregnancy. We aimed to characterize the hemodynamic profiles in pregnancies of advanced maternal age (AMA) and correlate these with fetal outcomes.

STUDY DESIGN

This was a prospective observational study of pregnancies undergoing antenatal testing. Maternal hemodynamics were measured non-invasively using an imaging probe at the descending aorta and the Uscom BP + arm cuff utilizing pulse pressure wave analysis. The Wilcoxon rank-sum test, Fisher's exact test, and Spearman rank correlation test were used for statistical analysis in R.

MAIN OUTCOME MEASURES

Hemodynamic measurements, neonatal birthweight.

RESULTS

Twenty-one AMA and twenty-four control patients were enrolled. Mean age ± SD was 39 ± 3.22 in the AMA cohort and 28 ± 4.32 in the control cohort (p < 0.001). AMA patients were evaluated at a later gestational age (36 4/7 weeks) compared to control (34 1/7 weeks, p = 0.02). Between groups, there was no difference in BMI, race, hypertensive disease, diabetes, asthma, drug use, or indication for antenatal testing. 38% (AMA) and 37% (control) had hypertensive disorders of pregnancy. In AMA patients but not control patients, cardiac output (r = 0.52, p = 0.01), systemic vascular resistance (r = -0.53, p = 0.01), and systemic vascular resistance index (r = -0.62, p = 0.002) were significantly correlated with neonatal birthweight percentile.

CONCLUSIONS

Hemodynamic alterations consistent with a low output, high resistance cardiovascular circuit were associated with lower birthweight in AMA, but not in control pregnancies.

Clinical consequences of developmental programming of low nephron number

Nephron number in humans varies up to 13-fold, likely reflecting the impact of multiple factors on kidney development, including inherited body size and ethnicity, as well as maternal health and nutrition, fetal exposure to gestational diabetes or preeclampsia and other environmental factors, which may potentially be modifiable. Such conditions predispose to low or high offspring birth weight, growth restriction or preterm birth, which have all been associated with increased risks of higher blood pressures and/or kidney dysfunction in later life. Low birth weight, preterm birth, and intrauterine growth restriction are associated with reduced nephron numbers. Humans with hypertension and chronic kidney disease tend to have fewer nephrons than their counterparts with normal blood pressures or kidney function. A developmentally programmed reduction in nephron number therefore enhances an individual's susceptibility to hypertension and kidney disease in later life. A low nephron number at birth may not lead to kidney dysfunction alone except when severe, but in the face of superimposed acute or chronic kidney injury, a kidney endowed with fewer nephrons may be less able to adapt, and overt kidney disease may develop. Given that millions of babies are born either too small, too big or too soon each year, the population impact of altered renal programming is likely to be significant. Many gestational exposures are modifiable, therefore urgent attention is required to implement public health measures to optimize maternal, fetal, and child health, to prevent or mitigate the consequences of developmental programming, to improve the health future generations.

Cardiac maladaptation in obese pregnant women at term

OBJECTIVE

Obesity is an increasing problem worldwide, with well recognized detrimental effects on cardiovascular health; however, very little is known about the effect of obesity on cardiovascular adaptation to pregnancy. The aim of the present study was to compare biventricular cardiac function at term between obese pregnant women and pregnant women with normal body weight, utilizing conventional echocardiography and speckle-tracking assessment.

METHODS

This was a prospective case-control study of 40 obese, but otherwise healthy, pregnant women with a body mass index (BMI) of ≥ 35 kg/m² and 40 healthy pregnant women with a BMI of ≤ 30 kg/m² . All women underwent a comprehensive echocardiographic examination and speckle-tracking assessment at term.

RESULTS

Obese pregnant women, compared with controls, had significantly higher systolic blood pressure (117 vs 109 mmHg; P = 0.002), cardiac output (6.73 vs 4.90 L/min; P < 0.001), left ventricular (LV) mass index (74 vs 64 g/m² ; P < 0.001) and relative wall thickness (0.43 vs 0.37; P < 0.001). Diastolic dysfunction was present in five (12.5%) controls and 16 (40%) obese women (P = 0.004). In obese women, compared with controls, LV global longitudinal strain (-15.59 vs -17.61%; P < 0.001), LV endocardial (-17.30 vs -19.84%; P < 0.001) and epicardial (-13.10 vs -15.73%; P < 0.001) global longitudinal strain as well as LV early diastolic strain rate (1.05 vs 1.24 /s; P = 0.006) were all significantly reduced. No differences were observed in the degree of LV twist and torsion between the two groups.

CONCLUSIONS

Morbidly obese, but otherwise healthy, pregnant women at term had significant LV hypertrophy with evidence of diastolic dysfunction and impaired deformation indices compared with pregnant women of normal weight. These findings are likely to represent a maladaptive response of the heart to volume overload in obese pregnancy. The impact of theses changes on pregnancy outcome and long-term maternal outcome is unclear. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

The effect of parity on longitudinal maternal hemodynamics

BACKGROUND

Parous women have a lower risk for pregnancy complications, such as preeclampsia or delivery of small-for-gestational-age neonates. However, parous women are a heterogeneous group of patients because they contain a low-risk cohort with previously uncomplicated pregnancies and a high-risk cohort with previous pregnancies complicated by preeclampsia and/or small for gestational age. Previous studies examining the effect of parity on maternal hemodynamics, including cardiac output and peripheral vascular resistance, did not distinguish between parous women with and without a history of preeclampsia or small for gestational age and reported contradictory results.

OBJECTIVE

The objective of the study was to compare maternal hemodynamics in nulliparous women and in parous women with and without previous preeclampsia and/or small for gestational age.

STUDY DESIGN

This was a prospective, longitudinal study of maternal hemodynamics, assessed by a bioreactance method, measured at 11⁺⁰ to 13⁺⁶, 19⁺⁰ to 24⁺⁰, 30⁺⁰ to 34⁺⁰, and 35⁺⁰ to 37⁺⁰ weeks' gestation in 3 groups of women. Group 1 was composed of parous women without a history of preeclampsia and/or small for gestational age (n = 632), group 2 was composed of nulliparous women (n = 829), and group 3 was composed of parous women with a history of preeclampsia and/or small for gestational age (n = 113). A multilevel linear mixed-effects model was performed to compare the repeated measures of hemodynamic variables controlling for maternal characteristics, medical history, and development of preeclampsia or small for gestational age in the current pregnancy.

RESULTS

In groups 1 and 2, cardiac output increased with gestational age to a peak at 32 weeks and peripheral vascular resistance showed a reversed pattern with its nadir at 32 weeks; in group 1, compared with group 2, there was better cardiac adaptation, reflected in higher cardiac output and lower peripheral vascular resistance. In group 3 there was a hyperdynamic profile of higher cardiac output and lower peripheral vascular resistance at the first trimester followed by an earlier sharp decline of cardiac output and increase of peripheral vascular resistance from midgestation. The incidence of preeclampsia and small for gestational age was highest in group 3 and lowest in group 1.

CONCLUSION

There are parity-specific differences in maternal cardiac adaptation in pregnancy.

Maternal hemodynamics in screen-positive and screen-negative women of the ASPRE trial

OBJECTIVE

To compare maternal hemodynamics and perinatal outcome, in pregnancies that do not develop pre-eclampsia (PE) or deliver a small-for-gestational-age (SGA) neonate, between those identified at 11-13 weeks' gestation as being screen positive or negative for preterm PE, by a combination of maternal factors, mean arterial pressure, uterine artery pulsatility index, serum placental growth factor and pregnancy associated plasma protein-A.

METHODS

This was a prospective longitudinal cohort study of maternal cardiovascular function, assessed using a bioreactance method, in women undergoing first-trimester screening for PE. Maternal hemodynamics and perinatal outcome were compared between screen-positive and screen-negative women who did not have a medical comorbidity, did not develop PE or pregnancy-induced hypertension and delivered at term a live neonate with birth weight between the 5^th and 95^th percentiles. A multilevel linear mixed-effects model was used to compare the repeated measures of cardiac variables, controlling for maternal characteristics.

RESULTS

The screen-negative group (n = 926) had normal cardiac function changes across gestation, whereas the screen-positive group (n = 170) demonstrated static or reduced cardiac output and stroke volume and higher mean arterial pressure and peripheral vascular resistance with advancing gestation. In the screen-positive group, compared with screen-negative women, birth-weight Z-score was shifted toward lower values, with prevalence of delivery of a neonate below the 35^th , 30^th or 25^th percentile being about 70% higher, and the rate of operative delivery for fetal distress in labor also being higher.

CONCLUSION

Women who were screen positive for impaired placentation, even though they did not develop PE or deliver a SGA neonate, had pathological cardiac adaptation in pregnancy and increased risk of adverse perinatal outcome. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Low Volume Circulation in Normotensive Women Pregnant with Neonates Small for Gestational Age

BACKGROUND

Pregnancies complicated with small for gestational age (SGA) neonates are reported with maternal circulatory maladaptations.

OBJECTIVES

We aimed to understand the pathophysiology of the maternal circulation in normotensive SGA pregnancies and to point out the trimestral differences from those with appropriate-to-large (non-SGA [NGA]) neonates.

METHODS

An observational study was conducted in 3 trimestral cohorts of normotensive pregnancies, categorized after birth according to neonatal birth weight percentile (BW%) as SGA (BW% ≤10, n = 158) or NGA (BW% > 10, n = 1,038). Standardized electrocardiogram-Doppler ultrasound, impedance cardiography, and bio-impedance were used to assess the maternal heart, arteries, veins, and fluid.

RESULTS

Diastolic blood pressure and mean arterial pressure were not significantly different, unless in the third trimester. In SGA compared to NGA pregnancies, total peripheral resistance (TPR) was higher and total arterial compliance, cardiac output (CO), and total body water (TBW) were lower throughout pregnancy. Venous return-enhancing functions were activated. In NGA but not SGA pregnancies, a positive correlation was found between BW% and CO + TBW and a negative correlation between BW% and TPR.

CONCLUSIONS

SGA pregnancies are characterized by lower maternal body fluid volume and CO, while normal blood pressures are maintained via increased TPR already from the first trimester onwards. Pregnancy-induced hemodynamic changes are superimposed on these characteristics.

Correlation between uterine artery Doppler and the sFlt-1/PlGF ratio in different phenotypes of placental dysfunction

OBJECTIVE

To explore correlations between the sFlt-1/PlGF ratio and uterine arteries (UtA) Doppler indexes in placental dysfunction-related disorders (PDD).

METHODS

We prospectively included women with a singleton pregnancy with preeclampsia (PE) only (n = 22), preeclampsia with fetal growth restriction (FGR) (n = 32), FGR only (n = 12), or normal pregnancy (n = 29).

RESULTS

In PDDs, significantly positive correlations between the sFlt-1/PlGF ratio and the mean UtA pulsatility (mPI-UtA), as well as the resistance index (mRI-UtA) were found (p = 0.015, p = 0.019, respectively), but not in normal pregnancies. PDD with signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio and mPI-UtA, was found in 50.0%, and, by the increased sFlt-1/PlGF ratio and mRI-UtA, in 65.2%. PDD without signs of impaired placentation, evidenced by the increased sFlt-1/PlGF ratio but normal mPI-UtA, was found in 24.2%, and, by the increased sFlt-1/PlGF ratio but normal mRI-UtA, in 7.6%. A substantial proportion of women with signs of impaired placentation were diagnosed with FGR with or without PE.

CONCLUSION

In PDD, the sFlt-1/PlGF ratio and UtA Doppler indexes increase proportionally. Correlations between the sFlt-1/PlGF ratio and UtA Doppler indexes might help to distinguish between PDDs with and without impaired placentation. However, further studies are needed to explore the correlations in different phenotypes of PDD.

Body fluid volume homeostasis is abnormal in pregnancies complicated with hypertension and/or poor fetal growth

OBJECTIVES

To evaluate body water volumes and cardiac output in each trimester of pregnancies complicated with hypertension and/or poor fetal growth, relative to uncomplicated pregnancy.

METHODS

In this semi-longitudinal cohort study, a standardised non-invasive maternal hemodynamics assessment in first, second or third trimester was performed in 1068 women with uncomplicated pregnancy (UP), 75 with early onset (EPE) and 117 with late onset preeclampsia (LPE), 139 with gestational hypertension (GH), 129 with small for gestational age (SGA) neonates and 43 with essential hypertension (EH). Women with hypertension or SGA were included prior to onset of symptoms or at diagnosis of disease; 46% of women (758/1631) were assessed in ≥ 2 trimesters. Impedance cardiography and spectrum analysis were used to measure cardiac output, total body water (TBW), extracellular (ECW) and intracellular water (ICW). A linear mixed model was used for inter-trimestrial comparison of parity-, age- and BMI-corrected values within and between groups.

RESULTS

For all pregnancies, TBW is higher in each consecutive trimester, mainly due to increasing fraction of ECW (ECW%). Compared to first trimester UP, ECW and ECW% are higher in EPE whereas TBW, ECW and ICW are lower in SGA. Compared to inter-trimestrial differences in UP, abnormal changes for body water volumes are observed in GH, EPE and LPE and for CO in EPE and LPE. Changes in EH are not different from UP.

CONCLUSIONS

This study is the first to show that concomitant gestational changes of ECW and CO are different from UP already in preclinical stages of pregnancies complicated with hypertension and/or poor fetal growth, except EH. This finding highlights the relevance of early gestational assessment of maternal body fluid status in pregnancies at risk for hypertension or poor fetal growth.

Maternal hemodynamics, fetal biometry and Doppler indices in pregnancies followed up for suspected fetal growth restriction

OBJECTIVES

To assess whether, in a cohort of patients with a small-for-gestational-age (SGA) fetus with estimated fetal weight ≤ 10^th percentile, maternal hemodynamics, fetal biometry and Doppler indices at presentation can predict the subsequent development of an abnormal fetal Doppler index or delivery of a baby with birth weight < 3^rd percentile.

METHODS

This was a prospective observational cohort study conducted at a specialist clinic for the management of pregnancies with a SGA fetus at King's College Hospital, London, UK. The study population comprised 86 singleton pregnancies with a SGA fetus, presenting at a median gestational age of 32 (range, 26-35) weeks. We measured maternal cardiac function using a non-invasive transthoracic bioreactance monitor, as well as mean arterial pressure, fetal biometry, and umbilical artery (UA), fetal middle cerebral artery (MCA) and uterine artery (UtA) pulsatility indices (PI), and the deepest vertical pool of amniotic fluid. Z-scores of these variables were calculated based on reported reference ranges and the values were compared between pregnancies with evidence of an abnormal fetal Doppler index at presentation (Group 1), those that had developed an abnormal Doppler index at a subsequent visit (Group 2) and those that did not develop an abnormal Doppler index throughout pregnancy (Group 3). Abnormal fetal Doppler was defined as UA-PI > 95^th percentile and/or MCA-PI < 5^th percentile. Differences in measured variables at presentation were also compared between pregnancies delivering a baby with birth weight < 3^rd percentile and those delivering a baby with birth weight ≥ 3^rd percentile. Multivariate logistic regression analysis was used to determine significant predictors of birth weight < 3^rd percentile and evolution from normal to abnormal fetal Doppler.

RESULTS

In the study population, 14 (16%) cases were in Group 1, 19 (22%) in Group 2 and 53 (62%) in Group 3. Birth weight was < 3^rd percentile in 39 (45%) cases and ≥ 3^rd percentile in 47 (55%). There was decreased cardiac output and stroke volume and increased peripheral vascular resistance compared with a normal population, and the deviations from normal were most marked in Group 1. Pregnancies with birth weight < 3^rd percentile, compared with those with birth weight ≥ 3^rd percentile, had greater deviations from normal in fetal biometry, maternal cardiac output, stroke volume, heart rate, peripheral vascular resistance and UtA-PI. Multivariate logistic regression analysis demonstrated that, in the prediction of birth weight < 3^rd percentile, maternal hemodynamic profile provided significant improvement to the prediction provided by maternal demographics, fetal biometry, UtA-PI, UA-PI and MCA-PI (difference between areas under receiver-operating characteristics curves, 0.18 (95% CI, 0.06-0.29); P = 0.002). In contrast, there was no significant independent contribution from maternal hemodynamics in the prediction of the subsequent development of abnormal fetal Doppler.

CONCLUSIONS

In pregnancies with a SGA fetus, there is decreased maternal cardiac output and stroke volume and increased peripheral vascular resistance, and the deviations from normal are most marked in cases of redistribution in the fetal circulation and reduced amniotic fluid volume. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Association Between Prepregnancy Cardiovascular Function and Subsequent Preeclampsia or Fetal Growth Restriction

Preeclampsia and fetal growth restriction during pregnancy are associated with increased risk of maternal cardiovascular disease later in life. It is unclear whether this association is causal or driven by similar antecedent risk factors. Clarification requires recruitment before conception which is methodologically difficult with high attrition rates and loss of outcome numbers to nonconception/miscarriage. Few prospective studies have, therefore, been adequately powered to address these questions. We recruited 530 healthy women (mean age: 35.0 years) intending to conceive and assessed cardiac output, cardiac index, stroke volume, total peripheral resistance, mean arterial pressure, and heart rate before pregnancy. Participants were followed to completion of subsequent pregnancy with repeat longitudinal assessments. Of 356 spontaneously conceived pregnancies, 15 (4.2%) were affected by preeclampsia and fetal growth restriction. Women who subsequently developed preeclampsia/fetal growth restriction had lower preconception cardiac output (4.9 versus 5.8 L/min; P=0.002) and cardiac index (2.9 versus 3.3 L/min per meter²; P=0.031) while mean arterial pressure (87.1 versus 82.3 mm Hg; P=0.05) and total peripheral resistance (1396.4 versus 1156.1 dynes sec cm^-5; P<0.001) were higher. Longitudinal trajectories for cardiac output and total peripheral resistance were similar between affected and healthy pregnancies, but the former group showed a more exaggerated fall in mean arterial pressure in the first trimester, followed by a steeper rise and a steeper fall to postpartum values. Significant relationships were observed between cardiac output, total peripheral resistance, and mean arterial pressure and gestational epoch. We conclude that in healthy women, an altered prepregnancy hemodynamic phenotype is associated with the subsequent development of preeclampsia/fetal growth restriction.