Hypertensive disorders in twin versus singleton gestations. National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units

The association between neonatal birthweight discordance and preeclampsia in twin pregnancy

PURPOSE

To investigate the association between neonatal birthweight (NBW) discordance and preeclampsia (PE) in twin pregnancy.

METHODS

This was a single-center retrospective cohort study. Women with two live births in the First Affiliated Hospital of Sun Yat-sen University from January 2011 to June 2020 were eligible. They were classified into four groups based on the quartiles of NBW discordance in monochorionic (MC) and dichorionic (DC) twin pregnancy. The relationship between NBW discordance and the risk of PE was assessed by logistic regression, subgroup analyses was further analyzed.

RESULTS

A total of 1566 women were eligible for the final analysis, there were 445 MC cases and 1121 DC cases. No matter in monochorionic or dichorionic pregnancy, higher NBW discordance quartiles were associated with increased risks of PE. Compared with women in the lowest NBW discordance quartile, women in the highest NBW discordance quartile had approximately 3.6 and 6.0 times risk of PE in monochorionic and dichorionic pregnancy respectively. The association between quartiles of NBW discordance and the risk of PE were higher in dichorionic pregnancy than in monochorionic pregnancy. No matter in MC or DC pregnancy, no significant interaction effects were identified for maternal age, pregnancy body mass index, mode of conception and whether complicated with gestational diabetes mellitus.

CONCLUSIONS

The increased NBW discordance quartile was related to an increased risk of PE. Assessing estimated fetal weight discordance by using ultrasound in clinical practice to predict PE remained to be further researched.

Is Increasing Parity Associated with Adverse Perinatal Outcomes in Dichorionic Twin Gestations?

OBJECTIVE

 Dichorionic twins have increased risk of preterm birth and hypertensive disorders of pregnancy. Grand multiparity may be associated with adverse perinatal outcomes in singleton pregnancies, although the effect of increasing parity in twins is unclear. This study aimed to elucidate whether grand multiparity leads to adverse outcomes in dichorionic twins compared with multiparity and nulliparity.

STUDY DESIGN

 This was a retrospective review of dichorionic twins at a single institution between January 2008 and December 2019 comparing pregnancy outcomes among grand multiparity, multiparity, and nulliparity. Primary outcome was preterm birth less than 37 weeks. Multivariable regression controlled for differing demographics, prior preterm birth, use of reproductive technologies, and hypertensive disorders of pregnancy. Chi square and Fisher's exact were used for categorical variables and Kruskal-Wallis was used for continuous variables.

RESULTS

 A total of 843 (60.3%) pregnancies were nulliparous, 499 (35.7%) multiparous, and 57(4.1%) grand multiparous. Univariate analysis indicated that multiparous women had lower incidence of preterm birth less than 37, 34, and 32 weeks (57 vs. 51%, p = 0.04; 19.2 vs. 14.0%, p = 0.02; 9.6 vs. 5.6%, p = 0.01) and that grand multiparous women had lower incidence of preterm birth less than 34 weeks (19.2 vs. 5.3%, p = 0.008) compared with nulliparous women. Multivariable regression confirmed multiparous women had lower odds of preterm birth less than 34 and 32 weeks compared with nulliparous women (<34 wk: odds ratio [OR] = 0.69, 95% confidence interval [CI] = 0.49-0.97, p = 0.03; <32 wk: OR = 0.48, 95% CI = 0.29-0.79, p = 0.004) and that multiparous women (OR = 0.57, 95% CI = 0.42-0.77, p = 0.0002) and grand multiparous women (OR = 0.23, 95% CI = 0.08-0.68, p = 0.0074) had lower incidence of hypertensive disorders of pregnancy when compared with nulliparous women.

CONCLUSION

 Grand multiparity is not associated with adverse perinatal outcomes compared with nulliparity or multiparity in dichorionic twins. Increasing parity may protect against incidence of preterm birth and hypertensive disorders of pregnancy even among grand multiparous women.

KEY POINTS

· Incidence of preterm birth may decrease with increasing parity in twins.. · Hypertensive disorders of pregnancy may decrease with increasing parity in twins.. · Grand multiparity is not associated with adverse perinatal outcomes in twins..

Risk of adverse pregnancy outcomes in twin- and singleton-born women: An inter-generational cohort study

OBJECTIVE

To compare the risk of adverse pregnancy outcomes between twin-born and singleton-born women. We also evaluated whether in utero exposure to pre-eclampsia or preterm delivery affected adverse pregnancy outcomes in women's own pregnancies.

DESIGN

Population-based cohort study.

SETTING

Medical Birth Registry of Norway 1967-2020.

POPULATION

9184 twin-born and 492 894 singleton-born women during 1967-2005, with their later pregnancies registered during 1981-2020.

METHODS

Data from an individual's birth were linked to their later pregnancies. We used generalised linear models with log link binomial distribution to obtain exponentiated regression coefficients that estimated relative risks (RRs) with 95% confidence intervals (CIs) for associations between twin- or singleton-born women and later adverse pregnancy outcomes.

MAIN OUTCOME MEASURES

Pre-eclampsia, preterm delivery or perinatal loss in twin-born compared with singleton-born women.

RESULTS

There was no increased risk for adverse outcomes in twin-born compared with singleton-born women: adjusted RRs for pre-eclampsia were 1.00 (95% CI 0.93-1.09), for preterm delivery 0.96 (95% CI 0.90-1.02) and for perinatal loss 1.00 (95% CI 0.84-1.18). Compared with singleton-born women exposed to pre-eclampsia in utero, twin-born women exposed to pre-eclampsia had lower risk of adverse outcomes in their own pregnancies; the aRR for pre-eclampsia was 0.73 (95% CI 0.58-0.91) and for preterm delivery was 0.71 (95% CI 0.56-0.90). Compared with preterm singleton-born women, preterm twin-born women did not differ in terms of risk of pre-eclampsia (aRR 1.05, 95% CI 0.92-1.21) or perinatal loss (aRR 0.99, 95% CI 0.71-1.37) and had reduced risk of preterm delivery (RR 0.83, 95% CI 0.74-0.94).

CONCLUSIONS

Twin-born women did not differ from singleton-born women in terms of risk of adverse pregnancy outcomes. Twin-born women exposed to pre-eclampsia in utero, had a lower risk of pre-eclampsia and preterm delivery compared with singleton-born women exposed to pre-eclampsia.

Risk Factors for Adverse Maternal Outcomes among Patients with Severe Preeclampsia Before 34 Weeks

OBJECTIVE

 This study aimed to characterize rates of maternal morbidity associated with early (<34 wk) preeclampsia with severe features and to determine factors associated with developing these morbidities.

STUDY DESIGN

 Retrospective cohort study of patients with early preeclampsia with severe features at a single institution from 2013 to 2019. Inclusion criteria were admission between 23 and 34 weeks and diagnosis of preeclampsia with severe features. Maternal morbidity defined as death, sepsis, intensive care unit (ICU) admission, acute renal insufficiency (acute kidney injury [AKI]), postpartum (PP) dilation and curettage, PP hysterectomy, venous thromboembolism (VTE), PP hemorrhage (PPH), PP wound infection, PP endometritis, pelvic abscess, PP pneumonia, readmission, and/or need for blood transfusion. Death, ICU admission, VTE, AKI, PP hysterectomy, sepsis, and/or transfusion of >2 units were considered severe maternal morbidity (SMM). Simple statistics used to compare characteristics among patients experiencing any morbidity and those not. Poisson regression used to assess relative risks.

RESULTS

 Of 260 patients included, 77 (29.6%) experienced maternal morbidity and 16 (6.2%) experienced severe morbidity. PPH (n = 46, 17.7%) was the most common morbidity, although 15 (5.8%) patients were readmitted, 16 (6.2%) needed a blood transfusion, and 14 (5.4%) had AKI. Patients who experienced maternal morbidity were more likely to be advanced maternal age, have preexisting diabetes, have multiples, and deliver nonvaginally (all ps < 0.05). Diagnosis of preeclampsia < 28 weeks or longer latency from diagnosis to delivery were not associated with increased maternal morbidity. In regression models, the relative risk of maternal morbidity remained significant for twins (adjusted odds ration [aOR]: 2.57; 95% confidence interval [CI]: 1.67, 3.96) and preexisting diabetes (aOR: 1.64; 95% CI: 1.04, 2.58), whereas attempted vaginal delivery was protective (aOR: 0.53; 95% CI: 0.30, 0.92).

CONCLUSION

 In this cohort, more than 1 in 4 patients diagnosed with early preeclampsia with severe features experienced maternal morbidity, whereas 1 in 16 patients experienced SMM. Twins and pregestational diabetes were associated with higher risk of morbidity, whereas attempted vaginal delivery was protective. These data may be helpful in promoting risk reduction and counseling patients diagnosed with early preeclampsia with severe features.

KEY POINTS

· One in four patients diagnosed with preeclampsia w/ severe features experienced maternal morbidity.. · One in 16 patients with preeclampsia w/ severe features experienced severe maternal morbidity.. · Factors most associated with morbidity/severe morbidity were twins and pregestational diabetes.. · Patients who attempted vaginal delivery appeared to have a lower rate of morbidity..

Association between gestational diabetes and cardiovascular disease within 24 months postpartum

BACKGROUND

Cardiovascular disease is the leading cause of death among women in the United States. It is well established that gestational diabetes mellitus is associated with an overall lifetime increased risk of cardiometabolic disease, even among those without intercurrent type 2 diabetes. However, the association between gestational diabetes mellitus and short-term risk of cardiovascular disease is unclear. Establishing short-term risks of cardiovascular disease for patients with gestational diabetes mellitus has significant potential to inform early screening and targeted intervention strategies to reduce premature cardiovascular morbidity among women.

OBJECTIVE

This study aimed to compare the risk of cardiovascular disease diagnosis in the first 24 months postpartum between patients with and without gestational diabetes mellitus.

STUDY DESIGN

Our longitudinal population-based study included pregnant individuals with deliveries from 2007 to 2019 in the Maine Health Data Organization's All Payer Claims Database. We excluded records with gestational age <20 weeks, non-Maine residence, multifetal gestation, no insurance in the month of delivery or the 3 months before pregnancy, an implausibly short interval until next pregnancy (<60 days), pregestational diabetes mellitus, and any prepregnancy diagnosis of the cardiovascular conditions being examined postpartum. Gestational diabetes mellitus and cardiovascular disease (heart failure, ischemic heart disease, arrhythmia/cardiac arrest, cardiomyopathy, cerebrovascular disease/stroke, and new chronic hypertension) were identified by International Classification of Diseases 9/10 diagnosis codes. Cox proportional hazards models were used to estimate hazard ratios, adjusting for potential confounding factors. We assessed whether the association between gestational diabetes mellitus and chronic hypertension was mediated by intercurrent diabetes mellitus.

RESULTS

Among the 84,746 pregnancies examined, the cumulative risk of cardiovascular disease within 24 months postpartum for those with vs without gestational diabetes mellitus was 0.13% vs 0.20% for heart failure, 0.16% vs 0.14% for ischemic heart disease, 0.60% vs 0.44% for cerebrovascular disease/stroke, 0.22% vs 0.16% for arrhythmia/cardiac arrest, 0.20% vs 0.20% for cardiomyopathy, and 4.19% vs 1.83% for new chronic hypertension. After adjusting for potential confounders, those with gestational diabetes had an increased risk of new chronic hypertension (adjusted hazard ratio, 1.56; 95% confidence interval, 1.32-1.86) within the first 24 months postpartum compared with those without gestational diabetes. There was no association between gestational diabetes and ischemic heart disease (adjusted hazard ratio, 0.75; 95% confidence interval, 0.34-1.65), cerebrovascular disease/stroke (adjusted hazard ratio, 1.13; 95% confidence interval, 0.78-1.66), arrhythmia/cardiac arrest (adjusted hazard ratio, 1.16; 95% confidence interval, 0.59-2.29), or cardiomyopathy (adjusted hazard ratio, 0.75; 95% confidence interval, 0.40-1.41) within the first 24 months postpartum. Those with gestational diabetes appeared to have a decreased risk of heart failure within 24 months postpartum (adjusted hazard ratio, 0.45; 95% confidence interval, 0.21-0.98). Our mediation analyses estimated that 28% of the effect of gestational diabetes on new chronic hypertension was mediated through intercurrent diabetes mellitus.

CONCLUSION

Patients with gestational diabetes mellitus have a significantly increased risk of new chronic hypertension as early as 24 months postpartum. Most of this effect was not due to the development of diabetes mellitus. Our findings suggest that all women with gestational diabetes need careful monitoring and screening for new chronic hypertension in the first 2 years postpartum.

The Association of Twin Chorionicity with Maternal Outcomes

OBJECTIVE

 Our objective was to investigate the association between maternal outcomes and twin chorionicity in a large, contemporary obstetric population.

STUDY DESIGN

 Retrospective cohort study was conducted at a single, large tertiary care center. Prenatal and inpatient records for all individuals with twin gestations were reviewed from 2000 to 2016. Patients with monoamniotic twins, higher-order multiples reduced to twins, multiple sets of twins in the study period, or undetermined chorionicity were excluded. Patients with monochorionic twins were compared with those with dichorionic twins. The co-primary outcomes were gestational diabetes mellitus and hypertensive disorders of pregnancy. Secondary outcomes included cesarean delivery, preterm delivery, postpartum hemorrhage, and other maternal outcomes. Bivariate and multivariate analyses were performed to assess associations of chorionicity with maternal outcomes.

RESULTS

 Of the 2,979 patients eligible for inclusion, 2,627 (88.2%) had dichorionic twin gestations and 352 (11.8%) had monochorionic twin gestations. Patients with monochorionic twins were less likely to self-identify as non-Hispanic White and to have conceived via assisted reproductive technology but were more likely to be publicly insured, multiparous and have prenatal care with a maternal-fetal medicine provider. Neither gestational diabetes mellitus (6.8% monochorionic vs. 6.2% dichorionic, p = 0.74; adjusted odds ratio [OR] 1.06, 95% confidence interval (CI) 0.60-1.86) nor hypertensive disorders of pregnancy (21.9% monochorionic vs. 26.3% dichorionic, p = 0.09; adjusted OR 0.99, 95% CI, 0.71-1.38) differed by chorionicity. Of the secondary maternal outcomes, patients with monochorionic twins experienced a lower frequency of cesarean delivery (46.0 vs. 61.8%, p < 0.001), which persisted after multivariate analyses (adjusted OR 0.60, 95% CI 0.46-0.80). There were no differences in preterm delivery, preterm premature rupture of membranes, hemorrhage, hysterectomy, or intrahepatic cholestasis of pregnancy.

CONCLUSION

 The odds of gestational diabetes mellitus and hypertensive disorders of pregnancy do not appear to differ by twin chorionicity.

KEY POINTS

· Hypertensive disorders of pregnancy do not differ by twin chorionicity.. · Gestational diabetes mellitus does not differ by twin chorionicity.. · Maternal outcomes are similar for individuals with monochorionic and dichorionic twin gestations..

The association between maternal insurance status on maternal and neonatal outcomes in women with hypertensive disorders of pregnancy

The objective of this study was to examine the association between maternal insurance status and maternal and neonatal adverse outcomes in women who had hypertensive disorders in pregnancy. A population-based retrospective cohort study was undertaken using the US Vital Statistics dataset on Period Linked Birth-Infant Data from 2016-2020. The study population was restricted to non-anomalous births from women whose pregnancies were complicated by hypertensive disorders. Insurance status was categorized as private, Medicaid, self-pay and other. The primary outcome was a composite of maternal adverse outcomes, which included admission to the intensive care unit, unplanned hysterectomy, maternal blood transfusion or uterine rupture. We examined the role of prenatal care in these relationships using a mediation analysis with Kotelchuck's Adequacy of Prenatal Care Utilization Index. Multivariable logistic regression models were used to estimate the association between maternal insurance status and adverse outcomes (using adjusted odds ratios [aOR] and 99% confidence interval [CI]). Of the 18,999,865 live births in the five-year study, 1,642,654 (8.6%) met the inclusion criteria. The frequency of the composite maternal adverse outcome was 1.3%. The maternal composite occurred more frequently in women with Medicaid (aOR = 1.11, 99% CI: 1.06, 1.16) or self-pay (aOR = 1.40, 99% CI: 1.25, 1.55) when compared to private insurance. Adjusting for prenatal care slightly attenuated this association, but remained significant. Among women with hypertensive disorders in pregnancy, women with Medicaid insurance or self-pay were more likely to experience maternal and neonatal adverse outcomes than women with private insurance.

Epidemiology and factors associated with preterm births in multiple pregnancy: a retrospective cohort study

OBJECTIVE

Multiple pregnancies carry an increased risk of maternal and perinatal complications, notably prematurity. Few studies have evaluated the risk factors for preterm births in multiple pregnancies within the Thai population. This study aims to ascertain maternal and perinatal outcomes and identify factors linked to preterm births in multiple pregnancies.

METHODS

This study was carried out at Khon Kaen University, Faculty of Medicine, Department of Obstetrics and Gynecology in Thailand. We reviewed the medical records of women with multiple pregnancies who delivered at a gestational age of more than 20 weeks between January 1, 2012 and December 31, 2021. We excluded patients with incomplete data or those for whom data were missing.

RESULTS

Out of 21,400 pregnancies, 427 were multiple pregnancies, constituting approximately 1.99%. Over the ten-year period, 269 multiple pregnancies (65.1%) resulted in preterm births. Of these, 173 (64.3%) were monochorionic twins, and 96 (35.7%) were dichorionic twins. Monochorionic twins had a notably higher rate of preterm delivery (AOR, 2.06; 95%CI 1.29-3.30). Vaginal delivery was observed in 7.9% of the cases, while cesarean sections were performed for both twins in 91.5% of cases. In 0.5% of the cases, only the second twin was delivered by cesarean section. In terms of neonatal outcomes, 160 infants (19.4%) weighed less than 1,500 g at birth, and there were 78 perinatal deaths (9.4%). Birth asphyxia was noted in 97 cases (20.2%) among monochorionic twins and in 28 cases (8.1%) for dichorionic twins.

CONCLUSION

The prevalence of multiple pregnancies was 1.99%, with 65.1% resulting in preterm births. Neonatal complications were notably more frequent in monochorionic twins. Monochorionic placenta and antepartum complications emerged as significant risk factors for preterm birth.

Timing of Delivery for Twins

The optimal gestational age for delivery of twin gestations balances the risk to the mother with the risks to the fetus and newborn. Primary considerations should include chorionicity and the presence or absence of other obstetrical complications such as fetal growth restriction or hypertensive disorders of pregnancy. More than half of twin gestations will deliver preterm, and a significant portion will be due to spontaneous labor or medical indications, such that the timing of delivery for twins is typically less determined by the provider discretion. Future studies are needed to assist in clarifying the optimal timing for delivery of twin pregnancies.

Risk factors for adverse outcomes in twin pregnancies: a narrative review

PURPOSE

Globally, the incidence of twin pregnancies is rising owing to the use of assisted reproductive technologies (ART), emigration and deferment of pregnancy until advanced maternal age (AMA). While twin pregnancies have higher absolute risks of adverse outcomes, including miscarriage, stillbirth, neonatal death and preterm delivery, the impact of specific exposures and risk factors related to these outcomes may differ between twin pregnancies and singleton pregnancies. Regarding modifiable factors, data are sometimes based on evidence extrapolated from singleton or whole obstetric populations. Therefore, targeted evidence is required to provide care tailored to twin pregnancies to prevent adverse outcomes. We aimed to comprehensively review the association between different risk factors and adverse outcomes in twin pregnancies, including data on chorionicity, and to compare these to singletons.

MATERIALS AND METHODS

This review examines the risks associated with chorionicity, AMA, body mass index (BMI), socioeconomic and ethnic inequalities, maternal smoking, use of ART, maternal perception of fetal movement, and maternal comorbidities, including hypertensive disorders of pregnancy (HDP) and gestational diabetes mellitus (GDM). Adverse outcomes reported were preterm birth, admission to the neonatal intensive care unit (NICU), stillbirth and neonatal mortality. As such, fetal mortality and morbidity will be under-represented, as pregnancy loss before 22-24 weeks is omitted.

RESULTS

Monochorionicity increases the risk of stillbirth, NICU admission, and preterm delivery in twin pregnancy. AMA predisposes twin pregnancies to higher risks of mortality, admission to the NICU, and preterm birth than singleton pregnancies do. Conversely, the impact of BMI, socioeconomic inequalities, smoking, ART, and HDP on adverse outcomes appears to be lower in twin pregnancies than in singleton pregnancies. This attenuation might be explained by the higher baseline risk of adverse outcomes such as preterm birth in twin pregnancies. Some exposures, such as ART use and GDM, appear to be "protective" against perinatal mortality in twin pregnancies, despite being established risk factors for adverse outcomes in singleton pregnancies, potentially related to access to specialist care. There is a paucity of evidence available to counsel mothers of twin pregnancies regarding reduced fetal movement.

CONCLUSIONS

Overall, the risk factors for adverse pregnancy outcomes differ between twin and singleton pregnancies. This highlights the need for further studies to examine the association between risk factors and adverse outcomes in twin pregnancies. The resulting data would facilitate tailored guidance for twin pregnancies, contribute to improved antenatal care, and inform wider public health strategies.

Hypertensive Disorders in Pregnancy: Global Burden From 1990 to 2019, Current Research Hotspots and Emerging Trends

Hypertensive disorders in pregnancy (HDP) constitute a worldwide health problem for pregnant women and their infants. This study provided HDP burden over 1990 to 2019 by region and age distribution, and predicted changes in related values for the next 25 years. We then conducted an econometric analysis of the author distribution, collaborative networks, keyword burst clustering, and spatio-temporal analysis of HDP-related publications from 2012 to 2022 to access current scientific developments and hotspots. The number of pregnant women with HDP has been increasing over the past 30 years, with regional and age-stratified differences in the burden of disease. Additionally, projections suggest an increase of deaths due to maternal HDP among adolescents younger than 20 years. Current research is mostly centered on pre-eclampsia, with hot keywords including trophoblast, immune tolerance, frozen-thawed embryo transfer, aspirin, gestational diabetes association, and biomarkers. Researches on the pathological mechanism, classification, and subtypes of HDP need to be further advanced.

Glycemic control and neonatal outcomes in twin pregnancies with gestational diabetes mellitus

BACKGROUND

Preliminary data suggest that strict glycemic control in twin pregnancies with gestational diabetes mellitus may not improve outcomes but might increase the risk of fetal growth restriction.

OBJECTIVE

This study aimed to investigate the association of maternal glycemic control with the risk of gestational diabetes mellitus-related complications and small for gestational age in twin pregnancies complicated by gestational diabetes mellitus.

STUDY DESIGN

This was a retrospective cohort study of all patients with a twin pregnancy complicated by gestational diabetes mellitus in a single tertiary center between 2011 and 2020, and a matched control group of patients with a twin pregnancy without gestational diabetes mellitus in a 1:3 ratio. The exposure was the level of glycemic control, described as the proportion of fasting, postprandial, and overall glucose values within target. Good glycemic control was defined as a proportion of values within target above the 50th percentile. The first coprimary outcome was a composite variable of neonatal morbidity, defined as at least 1 of the following: birthweight >90th centile for gestational age, hypoglycemia requiring treatment, jaundice requiring phototherapy, birth trauma, or admission to the neonatal intensive care unit at term. A second coprimary outcome was small for gestational age, defined as birthweight <10th centile or <3rd centile for gestational age. Associations between the level of glycemic control and the study outcomes were estimated using logistic regression analysis and were expressed as adjusted odds ratio with 95% confidence interval.

RESULTS

A total of 105 patients with gestational diabetes mellitus in a twin pregnancy met the study criteria. The overall rate of the primary outcome was 32.4% (34/105), and the overall proportion of pregnancies with a small for gestational age newborn at birth was 43.8% (46/105). Good glycemic control was not associated with a reduction in the risk of composite neonatal morbidity when compared with suboptimal glycemic control (32.1% vs 32.7%; adjusted odds ratio, 2.06 [95% confidence interval, 0.77-5.49]). However, good glycemic control was associated with higher odds of small for gestational age compared with nongestational diabetes mellitus pregnancies, especially in the subgroup of diet-treated gestational diabetes mellitus (65.5% vs 34.0%, respectively; adjusted odds ratio, 4.17 [95% confidence interval, 1.74-10.01] for small for gestational age <10th centile; and 24.1% vs 7.0%, respectively; adjusted odds ratio, 3.97 [95% confidence interval, 1.42-11.10] for small for gestational age <3rd centile). In contrast, the rate of small for gestational age in gestational diabetes mellitus pregnancies with suboptimal control was not considerably different when compared with non-gestational diabetes mellitus pregnancies. In addition, in cases of diet-treated gestational diabetes mellitus, good glycemic control was associated with a left-shift of the distribution of birthweight centiles, whereas the distribution of birthweight centiles among gestational diabetes mellitus pregnancies with suboptimal control was similar to that of nongestational diabetes mellitus pregnancies.

CONCLUSION

In patients with gestational diabetes mellitus in a twin pregnancy, good glycemic control is not associated with a reduction in the risk of gestational diabetes mellitus-related complications but may increase the risk of a small for gestational age newborn in the subgroup of patients with mild (diet-treated) gestational diabetes mellitus. These findings further question whether the gestational diabetes mellitus glycemic targets used in singleton pregnancies also apply to twin pregnancies and support the concern that applying the same diagnostic criteria and glycemic targets in twin pregnancies may result in overdiagnosis and overtreatment of gestational diabetes mellitus and potential neonatal harm.

Birthweight of the subsequent singleton pregnancy following a first twin or singleton pregnancy

INTRODUCTION

Birthweight is an important pregnancy indicator strongly associated with infant, child, and later adult life health. Previous studies have found that second-born babies are, on average, heavier than first-born babies, indicating an independent effect of parity on birthweight. Existing data are mostly based on singleton pregnancies and do not consider higher order pregnancies. We aimed to compare birthweight in singleton pregnancies following a first twin pregnancy relative to a first singleton pregnancy.

MATERIAL AND METHODS

This was a prospective registry-based cohort study using maternally linked offspring with first and subsequent pregnancies registered in the Medical Birth Registry of Norway between 1967 and 2020. We studied offspring birthweights of 778 975 women, of which 4849 had twins and 774 126 had singletons in their first pregnancy. Associations between twin or singleton status of the first pregnancy and birthweight (grams) in subsequent singleton pregnancies were evaluated by linear regression adjusted for maternal age at first delivery, year of first pregnancy, maternal education, and country of birth. We used plots to visualize the distribution of birthweight in the first and subsequent pregnancies.

RESULTS

Mean combined birthweight of first-born twins was more than 1000 g larger than mean birthweight of first-born singletons. When comparing mean birthweight of a subsequent singleton baby following first-born twins with those following first-born singletons, the adjusted difference was just 21 g (95% confidence interval 5-37 g).

CONCLUSIONS

Birthweights of the subsequent singleton baby were similar for women with a first twin or a first singleton pregnancy. Although first twin pregnancies contribute a greater combined total offspring birthweight including more extensive uterine expansion, this does not explain the general parity effect seen in birthweight. The physiological reasons for increased birthweight with parity remain to be established.

The adverse effect of gestational diabetes mellitus and hypertensive disorders of pregnancy on maternal-perinatal outcomes among singleton and twin pregnancies: a retrospective cohort study (2011-2019)

Background

Gestational diabetes mellitus (GDM) and hypertensive disorders of pregnancy (HDP) are the predominant pregnancy complications among singleton and twin pregnancies worldwide. Our primary objective was to explore the adverse effect of GDM and HDP on maternal-perinatal outcomes compared with non-GDM and non-HDP in singleton and twin pregnancies. The secondary objective was to find the risk of adverse maternal-perinatal outcomes in twin pregnancies compared with singleton pregnancies complicated with GDM and HDP in Hubei, China.

Methods

A tertiary hospital-based retrospective study was conducted at Wuhan University Renmin Hospital, Hubei Province, China, from 2011 to 2019. A chi-square test was used to determine the difference in adverse maternal-perinatal outcomes between singleton and twin pregnancies. A multiple binary logistic regression model and a joinpoint regression model were used to determine the association of GDM and HDP with adverse maternal-perinatal outcomes and GDM and HDP temporal trend among singleton and twin pregnancies.

Results

The trend of HDP [average annual percentage change (AAPC) 15.1% (95% confidence interval (95%CI): 5.3, 25.7)] among singleton pregnancies and GDM [AAPC 50.4% (95%CI: 19.9, 88.7)] among twin pregnancies significantly increased from 2011 to 2019. After adjusting for confounding factors, GDM is associated with an increased risk of C-section (adjusted odds ratio (aOR), 1.5; 95%CI: 1.3, 1.6) and macrosomia (aOR, 1.3; 95%CI: 1.1, 1.6) in singleton and preterm birth (PTB) (aOR, 2.1; 95%CI: 1.2, 3.3) in twin pregnancies compared with non-GDM. HDP was associated with a higher risk of C-section, PTB, perinatal mortality, and low birth weight (LBW) in both singleton and twin pregnancies compared with the non-HDP. Compared with singleton pregnancies complicated with GDM and HDP, twin pregnancies showed higher odds of C-section [(aOR, 1.7; 95%CI: 1.1, 2.7), (aOR, 4.6; 95%CI: 2.5, 8.7), respectively], PTB [(aOR, 22.9; 95%CI: 14.1, 37.3), (aOR, 8.1; 95%CI: 5.3, 12.3), respectively], LBW [(aOR, 12.1; 95%CI: 8.2, 18.1), (aOR, 5.1; 95%CI: 3.6, 7.4), respectively], and low Apgar score [(aOR, 8.2; 95%CI: 4.4, 15.1), (aOR, 3.8; 95%CI: 2.4, 5.8), respectively] complicated with GDM and HDP.

Conclusion

In conclusion, GDM showed an increased risk of a few adverse maternal-perinatal outcomes and HDP is associated with a higher risk of several adverse maternal-perinatal outcomes in singleton and twin pregnancies compared to non-GDM and non-HDP. Moreover, twin pregnancies complicated with GDM and HDP showed higher odds of adverse maternal-neonatal outcomes compared with singleton pregnancies complicated with GDM and HDP.

Exploring the efficacy and beneficial population of preimplantation genetic testing for aneuploidy start from the oocyte retrieval cycle: a real-world study

BACKGROUND

Preimplantation genetic testing for aneuploidy (PGT-A) is widely used as an embryo selection technique in in vitro fertilization (IVF), but its effectiveness and potential beneficiary populations are unclear.

METHODS

This retrospective cohort study included patients who underwent their first oocyte retrieval cycles at CITIC-Xiangya between January 2016 and November 2019, and the associated fresh and thawed embryo transfer cycles up to November 30, 2020. PGT-A (PGT-A group) and intracytoplasmic sperm injection (ICSI)/IVF (non-PGT-A group) cycles were included. The numbers of oocytes and embryos obtained were unrestricted. In total, 60,580 patients were enrolled, and baseline data were matched between groups using 1:3 propensity score matching. Sensitivity analyses, including propensity score stratification and traditional multivariate logistic regression, were performed on the original unmatched cohort to check the robustness of the overall results. Analyses were stratified by age, body mass index, ovarian reserve/responsiveness, and potential indications to explore benefits in subgroups. The primary outcome was cumulative live birth rate (CLBR). The other outcomes included live birth rate (LBR), pregnancy loss rate, clinical pregnancy rate, pregnancy complications, low birth weight rate, and neonatal malformation rate.

RESULTS

In total, 4195 PGT-A users were matched with 10,140 non-PGT-A users. A significant reduction in CLBR was observed in women using PGT-A (27.5% vs. 31.1%; odds ratio (OR) = 0.84, 95% confidence interval (CI) 0.78-0.91; P < 0.001). However, women using PGT-A had higher first-transfer pregnancy (63.9% vs. 46.9%; OR = 2.01, 95% CI 1.81-2.23; P < 0.001) and LBR (52.6% vs. 34.2%, OR = 2.13, 95% CI 1.92-2.36; P < 0.001) rates and lower rates of early miscarriage (12.8% vs. 20.2%; OR = 0.58, 95% CI 0.48-0.70; P < 0.001), preterm birth (8.6% vs 17.3%; P < 0.001), and low birth weight (4.9% vs. 19.3%; P < 0.001). Moreover, subgroup analyses revealed that women aged ≥ 38 years, diagnosed with recurrent pregnancy loss or intrauterine adhesions benefited from PGT-A, with a significant increase in first-transfer LBR without a decrease in CLBR.

CONCLUSION

PGT-A does not increase and decrease CLBR per oocyte retrieval cycle; nonetheless, it is effective in infertile populations with specific indications. PGT-A reduces complications associated with multiple gestations.

OX40 (CD134) Expression on T Regulatory Cells Is Related to Serious Hypertensive Disorders in Pregnancy

Hypertension is one of the leading causes of morbidity and mortality among women related to pregnancy, childbirth and the postpartum period. The pathogenesis of gestational hypertension is complex and still not fully understood. The aim of this study was to assess the population of circulating CD4+CD25+FoxP3+ cells and its differentiation in terms of OX40 expression in two forms of hypertension: isolated hypertension developing after the 20th week of pregnancy and pre-eclampsia. The study included a group of 60 patients with hypertension and 48 healthy controls. The analysis of the percentage of Tregs was performed by flow cytometry. There was no difference in the percentage of peripheral lymphocytes between the groups. In the group of women with preeclampsia compared to the group with gestational hypertension, significantly higher percentages of CD4+CD25+FoxP3+ cells (p = 0.03) and percentages of CD4+CD25+FoxP3+ cells expressing the OX40 antigen (p = 0.001) were observed. OX40 expression on Tregs seems to be related to more serious type of hypertensive disorders in pregnant women.

Advances in preeclampsia testing

Preeclampsia is a multisystem hypertensive disorder and one of the leading causes of maternal and fetal morbidity and mortality. The clinical hallmarks such as hypertension and proteinuria, and additional laboratory tests currently available including liver enzyme testing, are neither specific nor sufficiently sensitive. Therefore, biomarkers for timely and accurate identification of patients at risk of developing preeclampsia are extremely valuable to improve patient outcomes and safety. In this chapter, we will first discuss the clinical characteristics of preeclampsia and current evidence of the role of angiogenic factors, such as placental growth factor (PlGF) and soluble FMS like tyrosine kinase 1 (sFlt-1) in the pathogenesis of preeclampsia. Second, we will review the clinical practice guidelines for preeclampsia diagnostic criteria and their recommendations on laboratory testing. Third, we will review the currently available PlGF and sFlt-1 assays in terms of their methodologies, analytical performance, and clinical diagnostic values. Finally, we will discuss the future research needs from both an analytical and clinical perspective.

Association between hypertensive disorders of pregnancy and cardiovascular diseases within 24 months after delivery

BACKGROUND

Despite the well-known association between hypertensive disorders of pregnancy and cardiovascular diseases, there are limited data on which specific cardiovascular diagnoses have the greatest risk profiles during the first 24 months after delivery. Most existing data on hypertensive disorders of pregnancy and short-term cardiovascular disease risks are limited to the immediate postpartum period; however, it is crucial to determine cardiovascular disease risk up to 24 months after delivery to inform cardiovascular disease screening protocols during the extended postpartum period.

OBJECTIVE

This study aimed to delineate the risk of cardiovascular diagnoses in the first 24 months after delivery among patients with hypertensive disorders of pregnancy compared with patients without hypertensive disorders of pregnancy.

STUDY DESIGN

This longitudinal population-based study included pregnant individuals with deliveries during 2007 to 2019 in the Maine Health Data Organization's All Payer Claims Data. This study excluded patients with preexisting cardiovascular disease, with multifetal pregnancies, or without continuous insurance during pregnancy. Hypertensive disorders of pregnancy and cardiovascular diseases (categorized by specific conditions: heart failure, ischemic heart disease, arrhythmia or cardiac arrest, cardiomyopathy, cerebrovascular disease or stroke, and new chronic hypertension) were identified using International Classification of Diseases, Ninth Revision, and International Classification of Diseases, Tenth Revision, diagnosis codes. Cox proportional hazards models were used to estimate hazard ratios, adjusting for potential confounding factors.

RESULTS

Of the 119,422 pregnancies examined, the cumulative risk of cardiovascular disease within 24 months after delivery for those with hypertensive disorders of pregnancy vs those without hypertensive disorders of pregnancy was 0.6% vs 0.2% for heart failure, 0.3% vs 0.1% for ischemic heart disease, 0.2% vs 0.2% for arrhythmia or cardiac arrest, 0.6% vs 0.2% for cardiomyopathy, 0.8% vs 0.4% for cerebrovascular disease or stroke, 1.6% vs 0.7% for severe cardiac disease (composite outcome of heart failure, cerebrovascular disease or stroke, or cardiomyopathy), and 9.7% vs 1.5% for new chronic hypertension. After adjustment for potential confounders, those with hypertensive disorders of pregnancy had an increased risk of heart failure, cerebrovascular disease, cardiomyopathy, and severe cardiac disease within the first 24 months after delivery (adjusted hazard ratio, 2.81 [95% confidence interval, 1.90-4.15], 1.43 [95% confidence interval, 1.07-1.91], 2.90 [95% confidence interval, 1.96-4.27], and 1.90 [95% confidence interval, 1.54-2.30], respectively) compared with those without hypertensive disorders of pregnancy. In addition, those with hypertensive disorders of pregnancy had an increased risk for new chronic hypertension diagnosed after 42 days after delivery (adjusted hazard ratio, 7.29; 95% confidence interval, 6.57-8.09). There was no association between hypertensive disorders of pregnancy and ischemic heart disease (adjusted hazard ratio, 0.92; 95% confidence interval, 0.55-1.54) or cardiac arrest or arrhythmia (adjusted hazard ratio, 0.90; 95% confidence interval, 0.52-1.57). In addition, among women with hypertensive disorders of pregnancy, the highest proportion of first cardiovascular disease diagnoses occurred during the first month after delivery for cardiomyopathy (44%), heart failure (39%), cerebrovascular disease or stroke (39%), and severe cardiac disease (41%).

CONCLUSION

Patients with hypertensive disorders of pregnancy had an increased risk of developing new chronic hypertension, heart failure, cerebrovascular disease, and cardiomyopathy within 24 months after delivery. There was no association between hypertensive disorders of pregnancy and ischemic heart disease or cardiac arrest or arrhythmia. Patients with hypertensive disorders of pregnancy need targeted early postpartum interventions and increased monitoring in the first 24 months after delivery. This may preserve long-term health and improve maternal and neonatal outcomes in a subsequent pregnancy.

Adverse outcome following selective termination of presenting twin vs non-presenting twin

OBJECTIVE

Data are lacking on the impact on pregnancy outcome of the position of the abnormal fetus in a discordant twin pregnancy undergoing selective termination (ST). Tissue maceration post ST of the presenting twin may lead to early rupture of membranes, amnionitis and preterm labor. The aim of this study was to evaluate pregnancy complications and outcome following ST of the presenting vs non-presenting twin.

METHODS

This was a multicenter retrospective cohort study of dichorionic diamniotic twin pregnancies that underwent ST due to a discordant fetal anomaly (structural or genetic) between 2007 and 2021. The study population was divided into two groups according to the position of the reduced twin (presenting or non-presenting) and outcomes were studied accordingly. The primary outcome was a composite of early complications following ST, including infection, preterm prelabor rupture of membranes and pregnancy loss.

RESULTS

A total of 190 dichorionic twin pregnancies were included, of which 73 underwent ST of the presenting twin and 117 of the non-presenting twin. The groups did not differ in either baseline demographic characteristics or mean gestational age at the time of the procedure. ST of the presenting twin resulted in a significantly higher rate of early complications compared with the non-presenting twin (19.2% vs 7.7%; P = 0.018). Moreover, the rates of preterm delivery (75.3% vs 37.6%; P < 0.001) and neonatal intensive care unit admission (45.3% vs 17.1%; P < 0.001) were higher, and birth weight was lower (P < 0.001), in those pregnancies in which the presenting twin was reduced.

CONCLUSIONS

ST of the presenting twin resulted in a higher rate of adverse pregnancy outcome compared with that of the non-presenting twin. These findings should be acknowledged during patient counseling and, if legislation permits, taken into consideration when planning ST. © 2023 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Association of Prenatal Depression With New Cardiovascular Disease Within 24 Months Postpartum

Background Although depression is well established as an independent risk factor for cardiovascular disease (CVD) in the nonpregnant population, this association has largely not been investigated in pregnant populations. We aimed to estimate the cumulative risk of new CVD in the first 24 months postpartum among pregnant individuals diagnosed with prenatal depression compared with patients without depression diagnosed during pregnancy. Methods and Results Our longitudinal population-based study included pregnant individuals with deliveries during 2007 to 2019 in the Maine Health Data Organization's All Payer Claims Data. We excluded those with prepregnancy CVD, multifetal gestations, or no continuous health insurance during pregnancy. Prenatal depression and CVD (heart failure, ischemic heart disease, arrhythmia/cardiac arrest, cardiomyopathy, cerebrovascular disease, and chronic hypertension) were identified by International Classification of Diseases, Ninth Revision (ICD-9)/International Classification of Diseases, Tenth Revision (ICD-10) codes. Cox models were used to estimate hazard ratios (HRs), adjusting for potential confounding factors. Analyses were stratified by hypertensive disorder of pregnancy. A total of 119 422 pregnancies were examined. Pregnant individuals with prenatal depression had an increased risk of ischemic heart disease, arrhythmia/cardiac arrest, cardiomyopathy, and new hypertension (adjusted HR [aHR], 1.83 [95% CI, 1.20-2.80], aHR, 1.60 [95% CI, 1.10-2.31], aHR, 1.61 [95% CI, 1.15-2.24], and aHR, 1.32 [95% CI, 1.17-1.50], respectively). When the analyses were stratified by co-occurring hypertensive disorders of pregnancy, several of these associations persisted. Conclusions The cumulative risk of a new CVD diagnosis postpartum was elevated among individuals with prenatal depression and persists even in the absence of co-occurring hypertensive disorders of pregnancy. Further research to determine the causal pathway can inform postpartum CVD preventive measures.

Induction of Labor in Twins-Double Trouble?

OBJECTIVE

To determine and compare the safety and efficacy of different methods of induction of labor in twin gestations and their effect on maternal and neonatal outcomes.

METHODS

A retrospective observational cohort study was conducted at a single university-affiliated medical center. Patients with a twin gestation undergoing induction of labor at >32 + 0 weeks comprised the study group. Outcomes were compared to patients with a twin gestation at >32 + 0 weeks who went into labor spontaneously. The primary outcome was cesarean delivery. Secondary outcomes included operative vaginal delivery, postpartum hemorrhage, uterine rupture, 5 min APGAR < 7, and umbilical artery pH < 7.1. A subgroup analysis comparing outcomes for the induction of labor with oral prostaglandin E1 (PGE1), IV Oxytocin ± artificial rupture of membranes (AROM), and extra-amniotic balloon (EAB)+ IV Oxytocin was performed. Data were analyzed using Fisher's exact test, ANOVA, and chi-square tests.

RESULTS

268 patients who underwent induction of labor with a twin gestation comprised the study group. 450 patients with a twin gestation who went into labor spontaneously comprised the control group. There were no clinically significant differences between the groups for maternal age, gestational age, neonatal birthweight, birthweight discordancy, and non-vertex second twin. There were significantly more nulliparas in the study group compared to the control group (23.9% vs. 13.8% p < 0.001). The study group was significantly more likely to undergo a cesarean delivery of at least one twin (12.3% vs. 7.5% OR, 1.7 95% CI 1.04-2.85 p = 0.03). However, there was no significant difference in the rate of operative vaginal delivery (15.3% vs. 19.6% OR, 0.74, 95% CI 0.5-1.1 p = 0.16), PPH (5.2% vs. 6.9% OR, 0.75 95% CI 0.39-1.42 p = 0.37), 5-min APGAR scores < 7 (0% vs. 0.2% OR, 0.99 95%CI 0.99-1.00 p = 0.27), umbilical artery pH < 7.1 (1.5% vs. 1.3% OR, 1.12 95% CI 0.3-4.0), or combined adverse outcome (7.8% vs. 8.7% OR, 0.93 95% CI 0.6-1.4 p = 0.85). Furthermore, there were no significant differences in the rates of cesarean delivery or combined adverse outcomes in patients undergoing induction with oral PGE1 compared to IV Oxytocin ± AROM (13.3% vs. 12.5% OR, 1.1 95% CI 0.4-2.0 p = 1.0) (7% vs. 9.3% OR, 0.77 95% CI 0.5-3.5 p = 0.63 ) or EAB+ IV Oxytocin (13.3% vs. 6.9% OR, 2.1 95% CI 0.1-2.1 p = 0.53) (7% vs. 6.9% OR, 1.4 95% CI 0.15-3.5 p = 0.5) or between patients undergoing induction of labor with IV Oxytocin ± AROM and EAB+ IV Oxytocin (12.5% vs. 6.9% OR, 2.1 95% CI 0.1-2.4 p = 0.52) (9.3% vs. 6.9% OR, 0.98 95% CI 0.2-4.7 p = 0.54). There were no cases of uterine rupture in our study.

CONCLUSIONS

Induction of labor in twin gestations is associated with a two-fold increased risk of cesarean delivery, although this is not associated with adverse maternal or neonatal outcomes. Furthermore, the method of induction of labor used does not affect the chances of success nor the rate of adverse maternal or neonatal outcomes.

Fetal Growth Restriction and Long-Term Cardiovascular Morbidity of Offspring in Dichorionic-Diamniotic Twin Pregnancies

Objective: We opted to investigate whether fetal growth restriction (FGR) in dichorionic-diamniotic twins is a risk factor for long-term cardiovascular morbidity in offspring. Study design: A population-based retrospective cohort study, comparing long-term cardiovascular morbidity among FGR and non-FGR twins, born between the years 1991 and 2021 in a tertiary medical center. Study groups were followed until 18 years of age (6570 days) for cardiovascular-related morbidity. A Kaplan-Meier survival curve compared the cumulative cardiovascular morbidity. A Cox proportional hazard model assisted with adjusting for confounders. Results: In this study, 4222 dichorionic-diamniotic twins were included; 116 were complicated with FGR and demonstrated a significantly higher rate of long-term cardiovascular morbidity (4.4% vs. 1.3%, OR = 3.4, 95% CI 1.35-8.78, p = 0.006). The cumulative incidence of long-term cardiovascular morbidity was significantly higher among FGR twins (Kaplan-Meier Log rank test p = 0.007). A Cox proportional-hazard model found an independent association between FGR and long-term cardiovascular morbidity, when adjusted for both birth order and gender (adjusted HR 3.3, 95% CI 1.31-8.19, p = 0.011). Conclusions: FGR in dichorionic-diamniotic twins is independently associated with an increased risk for long-term cardiovascular morbidity in offspring. Therefore, increased surveillance may be beneficial.

Perspectives on the Use of Placental Growth Factor (PlGF) in the Prediction and Diagnosis of Pre-Eclampsia: Recent Insights and Future Steps

Pre-eclampsia (PE) is a complex multisystem disease of pregnancy that is becoming increasingly recognized as a state of angiogenic imbalance characterized by low concentrations of placental growth factor (PlGF) and elevated soluble fms-like tyrosine kinase (sFlt-1). PlGF is a protein highly expressed by the placenta with vasculogenic and angiogenic properties, which has a central role in spiral artery remodeling and the development of a low-resistance placental capillary network. PlGF concentrations are significantly lower in women with preterm PE, and these reduced levels have been shown to precede the clinical onset of disease. Subsequently, the clinical utility of maternal serum PlGF has been extensively studied in singleton gestations from as early as 11 to 13 weeks' gestation, utilizing a validated multimarker prediction model, which performs superiorly to the National Institute for Health and Care Excellence (NICE) and American College of Obstetricians and Gynecologists (ACOG) guidelines in the detection of preterm PE. There is extensive research highlighting the role of PlGF-based testing utilizing commercially available assays in accelerating the diagnosis of PE in symptomatic women over 20 weeks' gestation and predicting time-to-delivery, allowing individualized risk stratification and appropriate antenatal surveillance to be determined. "Real-world" data has shown that interpretation of PlGF-based test results can aid clinicians in improving maternal outcomes and a growing body of evidence has implied a role for sFlt-1/PlGF in the prognostication of adverse pregnancy and perinatal events. Subsequently, PlGF-based testing is increasingly being implemented into obstetric practice and is advocated by NICE. This literature review aims to provide healthcare professionals with an understanding of the role of angiogenic biomarkers in PE and discuss the evidence for PlGF-based screening and triage. Prospective studies are warranted to explore if its implementation significantly improves perinatal outcomes, explore the value of repeat PlGF testing, and its use in multiple pregnancies.

Adverse obstetric outcomes in women with PCOS and multiple gestations

RESEARCH QUESTION

Does multiple gestation alter the risks for adverse obstetric outcomes in women with polycystic ovary syndrome (PCOS)?

DESIGN

Retrospective population-based cohort study using data from the HCUP-NIS from 2004 to 2014. A total of 14,882 women with PCOS, who delivered within that time period, were identified. The study group comprised women with PCOS who had had a multiple gestation (n = 880); the reference group was comprised of the remaining women with PCOS and singleton gestation (n = 14,002).

RESULTS

In women with PCOS, multiple gestation increased the risks of pregnancy complications including pregnancy-induced hypertension (adjusted odds ratio [aOR] 2.030; 95% confidence interval [CI] 1.676-2.460), pre-eclampsia (aOR 2.879; 95% CI 2.277-3.639), pre-eclampsia and eclampsia superimposed on pre-existing hypertension (aOR 1.917; 95% CI 1.266-2.903) and gestational diabetes (aOR 1.358; 95% CI 1.114-1.656). Multiple gestation increases the risk of preterm premature rupture of membranes (aOR 5.807; 95% CI 4.153-8.119), preterm delivery (aOR 8.466; 95% CI 7.071-10.135), Caesarean section (aOR 5.146; 95% CI 4.184-6.329), post-partum haemorrhage (aOR 1.540; 95% CI 1.065-2.228) and the need for transfusion (aOR 3.268; 95% CI 2.010-5.314), as well as wound complications (aOR 3.089; 95% CI 1.647-5.794). Neonates born to mothers with PCOS and having multiple gestations are more likely to be small for gestational age when compared to singleton neonates born to mothers with PCOS (aOR 4.606; 95% CI 3.480-6.095). Among PCOS women with multiple gestations, obesity increased the risks of developing pregnancy-induced hypertension (P < 0.001), pre-eclampsia (P < 0.001) and wound complications (P = 0.045).

CONCLUSION

These results highlight the importance of single embryo transfer and ovulation induction to develop a single follicle in women with PCOS. Obesity further increases obstetrical complications.

Association of State Insurance Mandates for Fertility Treatment With Multiple Embryo Transfer After Preimplantation Genetic Testing for Aneuploidy

IMPORTANCE

Multiple gestation is one of the biggest risks after in vitro fertilization (IVF), largely due to multiple embryo transfer (MET). Single embryo transfer (SET) uptake has increased over time and has been attributed to various factors, such as mandated insurance coverage for IVF and preimplantation genetic testing for aneuploidy (PGT-A).

OBJECTIVE

To investigate whether mandates for IVF insurance coverage are associated with decreased use of MET after PGT-A.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study was conducted using data on embryo transfers reported to the Society for Assisted Reproductive Technology between 2014 and 2016. Data were analyzed from January to October 2021.

EXPOSURES

State-mandated coverage for fertility treatment and type of cycle transfer performed (PGT-A, untested fresh, and untested frozen).

MAIN OUTCOMES AND MEASURES

Use of MET compared with SET, live birth, and live birth of multiples.

RESULTS

There were 110 843 embryo transfers (mean [SD] patient age, 34.0 [4.5] years; 5520 individuals identified as African American [5.0%], 10 035 as Asian [9.0%], 5425 as Hispanic [4.9%], 45 561 as White [41.1%], and 44 302 as other or unknown race or ethnicity [40.0%]); 17 650 transfers used embryos that underwent PGT-A. Overall, among transferred embryos that had PGT-A, there were 9712 live births (55.0%). The odds of live birth were 70% higher with MET vs SET after frozen embryo transfer with PGT-A (OR, 1.70; 95% CI, 1.61-1.78), but the risk of multiples was 5 times higher (OR, 5.33; 95% CI, 5.22-5.44). The odds of MET in cycles with PGT-A in states with insurance mandates were 24% lower than in states without mandates (OR, 0.76; 95% CI, 0.68-0.85).

CONCLUSIONS AND RELEVANCE

This study found that despite the promise of using SET with PGT-A, MET after PGT-A was not uncommon. This practice was more common in states without insurance mandates and was associated with a high risk of multiples.

Aspirin Responsiveness at a Dose of 80 mg and Its Impact on Birth Weight when Used in Twin Pregnancies: The GAP Pilot Randomized Trial

OBJECTIVE

Daily aspirin, started in the first trimester of pregnancy, is commonly used for the prevention of preeclampsia and fetal growth restriction in multiple gestation. However, the optimal dose remains controversial and the evidence for the use of aspirin in multiple pregnancies is scarce. We aimed to estimate the impact of 80 mg of aspirin in twin pregnancies.

STUDY DESIGN

We performed a pilot double-blind randomized trial of women with twin pregnancies recruited between 8 and 14 weeks of gestation. Fifty participants (25 in each group) were randomized to 80 mg of aspirin daily at bedtime or a placebo from randomization until 36 weeks of gestation. Primary and secondary outcomes included the birth weight of live infants, preeclampsia, and aspirin responsiveness evaluated by a platelet aggregation test (platelet function assay [PFA]-100).

RESULTS

All participants were followed until birth, including 48 and 47 live newborns in the aspirin and the placebo groups, respectively. The mean birth weight difference between the aspirin (2,385 ± 529 g) and placebo (2,224 ± 706 g) groups was of 179 g (95% confidence interval [CI]: -172-531 g, p = 0.32). We observed two (8%) cases of preeclampsia in the aspirin group and no case with placebo (p = 0.49). Most importantly,16 of 24 participants who received aspirin (67%; 95% CI: 45-84%) had a normal PFA-100 test at 22 to 23 weeks, including the two cases of preeclampsia, suggesting that the majority of the participants were nonresponsive to 80 mg of aspirin.

CONCLUSION

Our results suggest that the majority of women with twin pregnancies showed a lack of response to a daily dose of 80 mg of aspirin according to the PFA-100 test, compared with the expected 29% of nonresponsiveness in singleton pregnancies. A daily dose of 80 mg of aspirin is likely to be insufficient for the prevention of preeclampsia and other placenta-mediated complications in twin pregnancies.

KEY POINTS

· Most women with twin pregnancies are nonresponsive to a daily dose of 80-mg aspirin.. · An 80 mg aspirin dose is insufficient to prevent placenta-mediated complications in twin pregnancies.. · Randomized trials using 100 to 160 mg of aspirin in twin pregnancies are needed..

Regulation of Placental Efflux Transporters during Pregnancy Complications

The placenta is essential for regulating the exchange of solutes between the maternal and fetal circulations. As a result, the placenta offers support and protection to the developing fetus by delivering crucial nutrients and removing waste and xenobiotics. ATP-binding cassette transporters, including multidrug resistance protein 1, multidrug resistance-associated proteins, and breast cancer resistance protein, remove chemicals through active efflux and are considered the primary transporters within the placental barrier. Altered transporter expression at the barrier could result in fetal exposure to chemicals and/or accumulation of xenobiotics within trophoblasts. Emerging data demonstrate that expression of these transporters is changed in women with pregnancy complications, suggesting potentially compromised integrity of placental barrier function. The purpose of this review is to summarize the regulation of placental efflux transporters during medical complications of pregnancy, including 1) placental inflammation/infection and chorioamnionitis, 2) hypertensive disorders of pregnancy, 3) metabolic disorders including gestational diabetes and obesity, and 4) fetal growth restriction/altered fetal size for gestational age. For each disorder, we review the basic pathophysiology and consider impacts on the expression and function of placental efflux transporters. Mechanisms of transporter dysregulation and implications for fetal drug and toxicant exposure are discussed. Understanding how transporters are up- or downregulated during pathology is important in assessing possible exposures of the fetus to potentially harmful chemicals in the environment as well as the disposition of novel therapeutics intended to treat placental and fetal diseases. SIGNIFICANCE STATEMENT: Diseases of pregnancy are associated with reduced expression of placental barrier transporters that may impact fetal pharmacotherapy and exposure to dietary and environmental toxicants.

Prospective observational comparison of arteria uterina blood flow between two frozen embryo transfer cycle regimens: natural cycle versus hormonal replacement cycle

PURPOSE

Is there a difference in the blood flow of the Arteria uterina in frozen embryo transfer (FET) cycles between a Natural Cycle (NC) and a Hormonal Replacement Therapy (HRT) cycle?

METHODS

Prospective observational study with measurement of the pulsatility index (PI) and resistance index (RI) throughout the ovarian stimulation cycle for IVF/ICSI, the FET cycle and at 12 weeks of gestation.

RESULTS

A total of 124 ovarian stimulation cycles with preimplantation genetic testing for aneuploidy (PGT-A) and "freeze-all" strategy due to PGT-A were included. Mean patient's age was 31.4 years, mean BMI 26.47 kg/m2, mean AMH 3.62 ng/ml and a mean AFC of 13. FET cycles were performed in 77 patients (NC protocol: 37.7%, HRT protocol: 62.2%). The overall pregnancy rate was 75%, (NC group: 79%, HRT-group 73%; not significant). No significant change of PI and RI was seen during hormonal stimulation. In FET cycles, there was a significant increase between cycle day 2/3 and ovulation/P4-start in the HRT-cycle, followed by a significant decrease until 12 weeks of gestation. The slope of the decrease in patients with a pregnancy in an HRT-approach was a bit steeper than in the NC-approach for both PI and RI, however, without a significant difference.

CONCLUSIONS

Early measurements of the blood flow parameters during the FET cycle do not reveal a difference between the NC- and the HRT-approach for FET, which could be predictive for development of pre-eclampsia.

Prediction of maternal complications and neonatal outcome in dichorionic diamniotic twins with fetal weight discordancy measured by ultrasonography

This study aimed to determine the relationship between estimated fetal weight discordance by ultrasonography and maternal and neonatal outcomes in dichorionic diamniotic twin pregnancies. We conducted a retrospective review of the medical records of 106 twin pregnancies delivered at a single tertiary center between January 2011 and February 2020. At 20–24 and 28–32 weeks of gestation, participants were divided into two groups: discordant twins with an estimated fetal weight difference of more than 20% and concordant twins with a weight difference of less than 20%. Maternal complications and neonatal outcomes were compared between the two groups. Although the incidences of preeclampsia and placenta previa were significantly higher in discordant twins measured between 20 and 24 weeks, no statistical significance was found in neonatal outcomes. Delivery times were earlier, and neonatal weights were lower in discordant twins measured between 28 and 32 weeks. Neonatal outcomes such as ventilator use and neurodevelopment were also significantly different. Discordance in estimated fetal weight measured using ultrasonography between 20 and 24 weeks can be a risk factor for maternal preeclampsia and placenta previa, whereas discordance at 28–32 weeks may predict poor neonatal outcomes.

Gestational hypertensive disease and small for gestational age infants in twin pregnancy: A systematic review and meta-analysis

AIM

The review is to explore the connection between gestational hypertension diseases (GHD) and small for gestational age (SGA) in twin pregnancies.

METHODS

According to the recommendations of PRISMA, relevant studies were systematically searched through PubMed, Web of Science, Cochrane Library, Embase from inception until January 16, 2022. Subgroup analysis was performed according to chorionicity and diagnostic criteria of SGA. Odds ratios (OR) were assessed to judge the link between GHD and SGA in twin pregnant women. A random-effect model was used to estimate the pooled hazard ratio when there was significant heterogeneity (I²  > 50%); otherwise, a fixed-effect model was conducted.

RESULTS

Seven articles containing 470 589 twin pregnant women were included. The increased risk of SGA was connected to the twin pregnancies complicated with GHD (OR = 1.57, 95% confidence interval [CI] = 1.10-2.24, p = 0.01). After subgroup analysis, the connection between SGA and GHD had no statistical significance (OR = 1.17, 95% CI = 0.95-1.44, p = 0.14) when the enrolled studies using the SGA diagnosis referred to singleton birth weight, but significant (OR = 2.14, 95% CI = 1.77-2.60, p<0.001) in the group using the SGA diagnosis referred to twin birth weight. Stratified by chorionicity, SGA was relevant to GHD in the dichorionic (DC) group (OR = 1.68, 95% CI = 1.17-2.42, p = 0.005), while not in the monochorionic (MC) group (OR = 1.68, 95% CI = 0.93-3.03, p = 0.09). More future articles are warranted to confirm these outcomes.

CONCLUSIONS

Our review demonstrated that GHD in DC twin pregnancies was related to an enlarged risk of SGA. Two SGA diagnosis references led to different results. Twin pregnancies complicated with GHD were at significantly higher risk of SGA when twin birth weight reference was used.

Results of a Five-Year Experience in First Trimester Preeclampsia Screening

Background and Objectives: The study aimed to evaluate the ability defining the risk of developing preeclampsia by a screening test carried out in the first trimester (between 11 + 0 and 13 + 6 weeks of gestational age), in order to identify high-risk women requiring more intensive health surveillance. The secondary objective was to evaluate the ability of this test to predict the risk of adverse obstetric outcomes such as fetal growth restriction, intrauterine fetal death, gestational hypertension, HELLP syndrome, placental abruption, and preterm birth. Materials and Methods: This was a single-center study, conducted at the Operative Unit of Obstetrics of the State Hospital of the Republic of San Marino. Medical history was collected at the time of enrolment in writing. Subsequently, obstetric outcomes were collected for each enrolled woman, through the analysis of medical records. Results: From October 2014 to May 2019, 589 pregnant women were recruited, of whom, 474 (80.5%) were included in the “low-risk” group, and 115 (19.5%) in the “high-risk” group. At the time of analysis of this population, the obstetric outcomes were available for 498 women (84.5%), while 91 cases (15.5%) were current pregnancies. The PI of the uterine arteries was not significantly different between the two study groups. Otherwise, a significant difference was highlighted for MAP, which is higher in the case of pregnancies at high risk based on the risk factors only, and for PAPP-A, higher in the case of low-risk pregnancies. Regarding the percentage of fetal DNA, according to the most recent literature data, in our series, we report a statistically significant difference of the average between the low and high-risk groups. Conclusions: In our study, we demonstrate that the multiparametric screening test for early PE performed well in identifying women at high risk of early PE, which certainly has the most severe maternal–fetal outcomes. The data reported that ASA intake at low doses is significantly higher in the population with high-risk tests for both early PE and late PE suggest once again that anamnestic evaluation plays an essential role in women’s screening.

Time trend analysis of perinatal mortality, stillbirth, and early neonatal mortality of multiple pregnancies for each gestational week from the year 2000 to 2019: A population-based study in Japan

Multiple pregnancies pose a high risk of morbidity and mortality in both mothers and infants; thus, obtaining reliable information based on a large population is essential to improve management. We used the maternal and child health statistics, which are published annually, from the database of the Ministry of Health, Labor, and Welfare. The data obtained were aggregated in 5-year intervals, and we used them to analyze the proportion of the number of births for each week of pregnancy to the total of each singleton and multiple pregnancy. For perinatal health indicators (perinatal mortality, stillbirth, and neonatal mortality), the obtained data were calculated and plotted on graphs for each week of pregnancy. Moreover, these indicators were calculated by dividing them into first twin and second twin fetuses. Stillbirth weights were aggregated in several groups, and a histogram was displayed. Between 2000 and 2019, there were 21,068,275 live births, 67,666 stillbirths, and 16,443 early neonatal deaths, excluding 7,148 (7,104 singletons, 44 multiple births) cases, in which the exact gestational weeks at birth were unknown. More than 95% of multiple pregnancies were twin births. Perinatal mortality, stillbirth, and early neonatal mortality rates in multiple pregnancies were the lowest at approximately 37 weeks of gestation and lower than those of single pregnancies at approximately 36 weeks of gestation. Perinatal mortality and stillbirth rates were higher during the delivery of the second twins than the first-born twins, but the early neonatal mortality rate remained approximately the same during the delivery of both twins. As the data in the government database are accumulated and published continuously, indicators can be calculated in the future using the method presented in this study. Further, our findings may be useful for policymaking related to managing multiple pregnancies.

The association between chronic liver diseases and preeclampsia

Background

Preeclampsia is a multisystem disorder characterized by an abnormal vascular response to placentation associated with increased systemic vascular resistance. As liver involvement is one of the main clinical features of preeclampsia, we sought to determine if there is an association between chronic liver diseases and preeclampsia.

Methods

A retrospective matched case–control analysis was conducted in a tertiary medical center. Three hundred eleven (311) pregnant women with preexisting chronic liver disease (study group), including viral and autoimmune hepatitis, non-alcoholic fatty liver, Wilson disease, and cirrhosis, were match for age, parity, and number of fetuses to 933 healthy pregnant women (control group). The primary outcome measure was the incidence of preeclampsia in each group. Secondary outcome measures were obstetrical and neonatal complications. Confounders found to be significant on univariate analysis were evaluated using logistic regression models, and odds ratios (OR) and confidence intervals (CI) were calculated.

Results

Preeclampsia was diagnosed in 28 women (9.0%) in the study group and 33 women (3.54%) in the control group (p < 0.001).

On multivariate analysis adjusted for maternal age, parity, previous preeclampsia, chronic hypertension, gestational diabetes mellitus, pregestational diabetes mellitus, antiphospholipid syndrome, and mode of conception, chronic liver disease was found to be an independent risk factor for preeclampsia (aOR 2.631, 95% CI 1.518–4.561). Although there was no difference in the gestational week at delivery between the groups (38.6 ± 2.13 vs. 38.8 ± 2.17 for study and control group, respectively, p = 0.410), the study group had a lower mean neonatal birthweight (3088 ± 551 vs. 3182 ± 566 g, p = 0.011). There were no between-group differences in the other parameters evaluated.

Conclusion

In our study, preexisting chronic liver disease was associated with a 2.6-fold increased risk of preeclampsia.

High risk and low prevalence diseases: Eclampsia

INTRODUCTION

Eclampsia is a rare partum and puerperal condition that carries a high rate of morbidity and mortality.

OBJECTIVE

This review highlights the pearls and pitfalls of the care of patients with eclampsia, including presentation, evaluation, and evidence-based management in the emergency department (ED).

DISCUSSION

Eclampsia is a hypertensive disease of pregnancy defined by new onset tonic-clonic, focal, or multifocal seizures or unexplained altered mental status in a pregnant or postpartum patient in the absence of other causative etiologies. However, signs and symptoms of preeclampsia and prodromes of eclampsia are often subtle and non-specific, making the diagnosis difficult. Thus, it should be considered in pregnant and postpartum patients who present to the ED. Laboratory testing including complete blood cell count, renal and liver function panels, electrolytes, glucose, coagulation panel, fibrinogen, lactate dehydrogenase, uric acid, and urinalysis, as well as imaging to include head computed tomography, can assist, but these evaluations should not delay management. Components of treatment include emergent obstetric specialist consultation, magnesium administration, and blood pressure control in patients with hypertension. Definitive treatment of eclampsia requires emergent delivery in pregnant patients. If consultants are not in-house, emergent stabilization and immediate transfer are required.

CONCLUSIONS

An understanding of eclampsia can assist emergency clinicians in rapid recognition and timely management of this potentially deadly disease.

Short-term neonatal and long-term infant outcome of late-preterm twins: nationwide population-based study

OBJECTIVES

To evaluate the short- and long-term outcome of late-preterm compared with term birth in twin pregnancy.

METHODS

This retrospective observational cohort study included all women who had a twin delivery between 1 January 2007 and 31 December 2010 recorded in the claims database of the Korea National Health Insurance, with at least one follow-up recorded in the database of the National Health Screening Program for Infants and Children. Outcomes were analyzed at the pregnancy level, with adverse outcome being defined as an adverse outcome in one or both twins, identified by a diagnosis according to the International Classification of Diseases 10^th Revision. The primary short-term outcome was composite morbidity, which included any of the following: transient tachypnea, respiratory distress syndrome, necrotizing enterocolitis, intraventricular hemorrhage and bronchopulmonary dysplasia. Long-term adverse outcome included any neurological or neurodevelopmental outcome, defined by prespecified neurological and developmental diagnoses; these were assessed by following up all neonates until the end of 2018, by which time they were 8-11 years of age. Outcomes were compared between twins delivered late preterm (34 + 0 to 36 + 6 weeks) and those delivered at term (≥ 37 weeks).

RESULTS

Among 17 189 women who delivered twins at ≥ 34 weeks of gestation during the study period, 5032 (29.27%) women delivered in the late-preterm period. On multivariate analysis, compared with the twins delivered at term, the late-preterm twins had an increased risk for the primary short-term outcome of composite morbidity (adjusted odds ratio (aOR), 2.09; 95% CI, 1.90-2.30), including transient tachypnea (aOR, 1.85; 95% CI, 1.64-2.09), respiratory distress syndrome (aOR, 2.31; 95% CI, 2.04-2.62), necrotizing enterocolitis (aOR, 2.10; 95% CI, 1.20-3.69) and intraventricular hemorrhage (aOR, 2.13; 95% CI, 1.46-3.11). For the long-term outcome, the late-preterm twins also had an increased risk for any neurological or neurodevelopmental outcome (adjusted hazard ratio, 1.14; 95% CI, 1.07-1.21).

CONCLUSIONS

Twins delivered in the late-preterm period have an increased risk for short- and long-term morbidity compared with twins delivered at term. These results should be considered when determining the timing of delivery in uncomplicated twin pregnancy. © 2021 International Society of Ultrasound in Obstetrics and Gynecology.

The Maternal-Neonatal Outcomes of Twin Pregnancies with Preeclampsia and Their Association with Assisted Reproductive Technology: A Retrospective Study

Objective: This study aimed to investigate the maternal−neonatal outcomes of twin pregnancies of mothers with preeclampsia and their association with assisted reproductive technology (ART). Methods: A retrospective study on the clinical and maternal−neonatal outcome data of 698 women with twin pregnancies who delivered in our hospital from December 2013 to September 2021 was conducted. Continuous variables were analyzed using a Student’s t-test or Wilcoxon rank-sum test. Categorical variables were analyzed using the Chi-square test. The risk factors of twin pregnancies with preeclampsia were analyzed by logistic regression. Results: The rate of twin pregnancy complicated by preeclampsia was 17.62% (123/698). Logistic regression analysis showed that ART increased the risk of preeclampsia in twin pregnancies (AOR: 1.868, 95% CI: 1.187−2.941). Mothers with preeclampsia carrying twins conceived with ART had a higher rate of delivery at gestational week < 34 (29.9% vs. 12.5%) and asphyxia of the neonate at 5 min after delivery (13.4% vs. 1.8%) than those with preeclampsia conceived without ART (p < 0.05). Conclusions: ART increases the risk of preeclampsia in twin pregnancies and the rate of adverse maternal−neonatal outcomes for twin pregnancies with preeclampsia. The policy of single embryo transfer is a method to reduce the adverse pregnancy outcomes of ART.

Delivery timing in dichorionic diamniotic twin pregnancies complicated by preeclampsia: a decision analysis

OBJECTIVE

To determine the optimal timing of delivery in Dichorionic-diamniotic (DCDA) pregnancies complicated by preeclampsia without severe features.

METHODS

A decision-analytic model was created to compare outcomes of expectant management vs. delivery from 34 to 37w0d. Outcomes included quality-adjusted life years (QALYs), development of severe preeclampsia, maternal mortality, maternal stroke, small for gestational age (SGA) due to fetal growth restriction (FGR) detected antenatally, stillbirth, cerebral palsy (CP), and neonatal mortality. Probabilities, utilities, and life expectancies were derived from the literature. Univariate analysis was used to evaluate the impact of delivery at various gestational ages. Maternal and neonatal outcomes were calculated for a theoretical cohort of 10,000 DCDA pregnancies with preeclampsia.

RESULTS

The optimal gestational age for delivery was 36w0d when the total QALYs (868,112) were highest. Delivery at 34w0d resulted in the fewest cases of severe preeclampsia, maternal mortality, and maternal stroke (0, 4, and 15 cases per 10,000, respectively). The incidence of each of these adverse outcomes increased with gestational age, with the greatest number of adverse outcomes at 37w0d (2452 cases of severe preeclampsia, eight maternal deaths, and 31 cases of maternal stroke per 10,000). Delivery at 34w0d resulted in the fewest cases of severe preeclampsia (0), maternal stroke (15), maternal mortality (4), stillbirth (0), and SGA (1183). However, this strategy was also associated with most cases of neonatal CP (91) and neonatal mortality (87).

CONCLUSION

DCDA twin pregnancies complicated by preeclampsia without severe features appear to have the best outcomes when delivered at 36w0d. Specifically, when compared to delivery at 37w0d, this strategy reduced maternal and neonatal morbidity and mortality.

A New Model for the Predicting the Risk of Preeclampsia in Twin Pregnancy

Objective

We aimed to develop an effective nomogram model for predicting the risk of preeclampsia in twin pregnancies.

Methods

The study was a retrospective cohort study of women pregnant with twins who attended antenatal care and labored between January 2015 and December 2020 at the Fujian Maternity and Child Health Hospital, China. We extracted maternal demographic data and clinical characteristics. Then we performed the least absolute shrinkage and selection operator regression combined with clinical significance to screen variables. Thereafter, multivariate logistic regression was used to construct a nomogram that predicted the risk of preeclampsia in twin pregnancies. Finally, the nomogram was validated using C-statistics (C-index) and calibration curves.

Results

A total of 2,469 women with twin pregnancies were included, of whom 325 (13.16%) had preeclampsia. Multivariate logistic regression models revealed that serum creatinine, uric acid, mean platelet volume, high-density lipoprotein, lactate dehydrogenase, fibrinogen, primiparity, pre-pregnancy body mass index, and regular prenatal were independently associated with preeclampsia in twin pregnancies. The constructed predictive model exhibited a good discrimination and predictive ability for preeclampsia in twin pregnancies (concordance index 0.821).

Conclusion

The model for the prediction of preeclampsia in twin pregnancies has high accuracy and specificity. It can be used to assess the risk of preeclampsia in twin pregnancies.

Screening for preeclampsia in twin pregnancies

Twin pregnancies are an important risk factor for preeclampsia, a hypertensive disorder of pregnancy that is associated with a significant risk of maternal and perinatal morbidity. Given the burden of preeclampsia, the identification of women at high risk in early pregnancy is essential to allow for preventive strategies and close monitoring. In singleton pregnancies, the risk factors for preeclampsia are well established, and a combined first-trimester prediction model has been shown to adequately predict preterm disease. Furthermore, intervention with low-dose aspirin at 150 mg/day in those identified as high-risk reduces the rate of preterm preeclampsia by 62%. In contrast, risk factors for preeclampsia in twin pregnancies are less established, the proposed screening models have shown poor performance with high false-positive rates, and the benefit of aspirin for the prevention of preeclampsia is not clearly demonstrated. In this review, we examine the literature assessing prediction and prevention of preeclampsia in twin pregnancies.

Experience in different modes of delivery in twin pregnancy

Background/purpose

Vaginal delivery, compared with Cesarean delivery, remains a less chosen mode of delivery for twin pregnancy. We studied the maternal and perinatal outcomes of twin pregnancy with different modes of delivery.

Methods

A retrospective study with data collected from a regional hospital, including vital twin pregnancies delivered at gestational age of 32 weeks and above. Medical charts were reviewed for prenatal conditions and postpartum outcomes.

Results

Ninety-eight pairs of twins were included and 44.9% were delivered via vaginal delivery. Women in the vaginal delivery group were significantly younger (32.5 ±4.3 years versus 34.8 ±4.6 years, p < 0.01), multiparous (34.1% versus 18.5%) and with more twins in vertex-vertex presentation (70.5% versus 33.3%) compared with women in the Cesarean delivery group. There were no differences between maternal postpartum complications and neonatal outcomes in both groups. The outcomes showed longer inter-twin delivery time interval (5.7 ± 5.6 versus 1.5 ± 0.9 min, p < 0.01), less estimated blood loss (198.7 ± 144.1 versus 763.2 ± 332.3 mL, p < 0.01), and shorter maternal hospital stay (3.0 ± 0.5 versus 5.7 ± 0.5 days, p< 0.01) in the vaginal delivery group. Twenty newborns had Apgar score below seven at birth. Logistic regression analysis revealed that low Apgar score was independently related to younger maternal age, maternal obstetric diseases and fetal non-vertex presentation. Gestational weeks and mode of delivery were not related to low Apgar score.

Conclusion

With careful case selection, vaginal delivery could be safely performed in twin pregnancies with less estimated blood loss and better recovery than Cesarean delivery.

Vanquishing multiple pregnancy in in vitro fertilization in the United States-a 25-year endeavor

The practice of in vitro fertilization has changed tremendously since the birth of the first in vitro fertilization infant in 1978. With the success of early in vitro fertilization programs in the United States, there was a substantial rise in twin births nationwide. In the mid-1990s, more than 30% of in vitro fertilization cycles resulted in twin or higher-order multifetal pregnancies. Since that time, we not only have witnessed improvements in laboratory and treatment efficacy but also have seen a dramatic impact on pregnancy outcomes, specifically regarding twin pregnancies. Because the field evolved and the risks of multifetal pregnancies became more salient, in 2019, the rate of twin pregnancies had dropped to <7% of cycles. This improvement was largely because of technical advancements and revised professional guidance: culturing embryos longer before transfer, improved freezing technology, embryo preimplantation genetic testing, and revised professional guidance regarding the number of embryos to transfer. These developments have led to single-embryo transfer becoming the standard of care in most scenarios. We used national in vitro fertilization surveillance data of all autologous in vitro fertilization cycles from 1996 to 2019 to illustrate trends in the following improved outcomes: autologous embryo transfer cycles involving blastocyst-stage embryos, vitrified embryos, preimplantation genetic testing cycles, total number of embryos being transferred per cycle, and single-embryo transfer usage over time. Among deliveries from autologous embryo transfers, we highlighted trends in singleton births over time and proportion of deliveries involving twins, triplets, quadruplets, or greater. The notable progress in reducing the rate of multifetal pregnancies with in vitro fertilization was largely attributed to a series of technical and clinical actions, culminating in an 80% reduction in the incidence of multiple births without a loss in overall treatment effectiveness.

Incidence and Implications of Twin Gestational Surrogacy at Two Large U.S. Military Hospitals: A 10-Year Retrospective Cohort Study

INTRODUCTION

Individuals seeking a gestational surrogate often turn to U.S. military dependents due to favorable insurance coverage. Surrogate pregnancies, including multiple gestations, may be at increased risk for adverse outcomes. The objectives of this study were to determine the incidence of surrogacy in a twin population conceived by assisted reproductive technology (ART), assess the impact on the military healthcare system, and determine if there is an increased rate of complications in twin surrogacy pregnancies.

MATERIALS AND METHODS

We conducted a 10-year retrospective cohort study of ART-conceived twin gestations at two military hospitals. Charts were reviewed for demographic data, surrogacy status, and obstetric complications. Number of prenatal visits and formal sonograms were tabulated for surrogate pregnancies. Complication rates were compared between groups using Fisher's exact test.

RESULTS

Over the 10-year period, 36 of the 249 pregnancies were identified as gestational surrogates, equating to a rate of 14.4%. Surrogate mothers were younger than non-surrogates (29.58 years vs. 33.11 years, P < .001). Care of surrogate pregnancies required a total of 306 prenatal visits and 98 formal ultrasounds. The incidence of gestational diabetes was higher among surrogates compared to other ART-conceived twin pregnancies at 27.8% vs. 12.2% (P < .05), while other complications did not significantly differ.

CONCLUSIONS

Approximately one in seven ART-conceived twin gestations were surrogacy pregnancies, requiring significant clinical resources. The incidence of gestational diabetes was higher among surrogate gestations.

Eclampsia in the 21st century

The reported incidence of eclampsia is 1.6 to 10 per 10,000 deliveries in developed countries, whereas it is 50 to 151 per 10,000 deliveries in developing countries. In addition, low-resource countries have substantially higher rates of maternal and perinatal mortalities and morbidities. This disparity in incidence and pregnancy outcomes may be related to universal access to prenatal care, early detection of preeclampsia, timely delivery, and availability of healthcare resources in developed countries compared to developing countries. Because of its infrequency in developed countries, many obstetrical providers and maternity units have minimal to no experience in the acute management of eclampsia and its complications. Therefore, clear protocols for prevention of eclampsia in those with severe preeclampsia and acute treatment of eclamptic seizures at all levels of healthcare are required for better maternal and neonatal outcomes. Eclamptic seizure will occur in 2% of women with preeclampsia with severe features who are not receiving magnesium sulfate and in <0.6% in those receiving magnesium sulfate. The pathogenesis of an eclamptic seizure is not well understood; however, the blood-brain barrier disruption with the passage of fluid, ions, and plasma protein into the brain parenchyma remains the leading theory. New data suggest that blood-brain barrier permeability may increase by circulating factors found in preeclamptic women plasma, such as vascular endothelial growth factor and placental growth factor. The management of an eclamptic seizure will include supportive care to prevent serious maternal injury, magnesium sulfate for prevention of recurrent seizures, and promoting delivery. Although routine imagining following an eclamptic seizure is not recommended, the classic finding is referred to as the posterior reversible encephalopathy syndrome. Most patients with posterior reversible encephalopathy syndrome will show complete resolution of the imaging finding within 1 to 2 weeks, but routine imaging follow-up is unnecessary unless there are findings of intracranial hemorrhage, infraction, or ongoing neurologic deficit. Eclampsia is associated with increased risk of maternal mortality and morbidity, such as placental abruption, disseminated intravascular coagulation, pulmonary edema, aspiration pneumonia, cardiopulmonary arrest, and acute renal failure. Furthermore, a history of eclamptic seizures may be related to long-term cardiovascular risk and cognitive difficulties related to memory and concentration years after the index pregnancy. Finally, limited data suggest that placental growth factor levels in women with preeclampsia are superior to clinical markers in prediction of adverse pregnancy outcomes. This data may be extrapolated to the prediction of eclampsia in future studies. This summary of available evidence provides data and expert opinion on possible pathogenesis of eclampsia, imaging findings, differential diagnosis, and stepwise approach regarding the management of eclampsia before delivery and after delivery as well as current recommendations for the prevention of eclamptic seizures in women with preeclampsia.

Prevention of preeclampsia with aspirin

Preeclampsia is defined as hypertension arising after 20 weeks of gestational age with proteinuria or other signs of end-organ damage and is an important cause of maternal and perinatal morbidity and mortality, particularly when of early onset. Although a significant amount of research has been dedicated in identifying preventive measures for preeclampsia, the incidence of the condition has been relatively unchanged in the last decades. This could be attributed to the fact that the underlying pathophysiology of preeclampsia is not entirely understood. There is increasing evidence suggesting that suboptimal trophoblastic invasion leads to an imbalance of angiogenic and antiangiogenic proteins, ultimately causing widespread inflammation and endothelial damage, increased platelet aggregation, and thrombotic events with placental infarcts. Aspirin at doses below 300 mg selectively and irreversibly inactivates the cyclooxygenase-1 enzyme, suppressing the production of prostaglandins and thromboxane and inhibiting inflammation and platelet aggregation. Such an effect has led to the hypothesis that aspirin could be useful for preventing preeclampsia. The first possible link between the use of aspirin and the prevention of preeclampsia was suggested by a case report published in 1978, followed by the first randomized controlled trial published in 1985. Since then, numerous randomized trials have been published, reporting the safety of the use of aspirin in pregnancy and the inconsistent effects of aspirin on the rates of preeclampsia. These inconsistencies, however, can be largely explained by a high degree of heterogeneity regarding the selection of trial participants, baseline risk of the included women, dosage of aspirin, gestational age of prophylaxis initiation, and preeclampsia definition. An individual patient data meta-analysis has indicated a modest 10% reduction in preeclampsia rates with the use of aspirin, but later meta-analyses of aggregate data have revealed a dose-response effect of aspirin on preeclampsia rates, which is maximized when the medication is initiated before 16 weeks of gestational age. Recently, the Aspirin for Evidence-Based Preeclampsia Prevention trial has revealed that aspirin at a daily dosage of 150 mg, initiated before 16 weeks of gestational age, and given at night to a high-risk population, identified by a combined first trimester screening test, reduces the incidence of preterm preeclampsia by 62%. A secondary analysis of the Aspirin for Evidence-Based Preeclampsia Prevention trial data also indicated a reduction in the length of stay in the neonatal intensive care unit by 68% compared with placebo, mainly because of a reduction in births before 32 weeks of gestational age with preeclampsia. The beneficial effect of aspirin has been found to be similar in subgroups according to different maternal characteristics, except for the presence of chronic hypertension, where no beneficial effect is evident. In addition, the effect size of aspirin has been found to be more pronounced in women with good compliance to treatment. In general, randomized trials are underpowered to investigate the treatment effect of aspirin on the rates of other placental-associated adverse outcomes such as fetal growth restriction and stillbirth. This article summarizes the evidence around aspirin for the prevention of preeclampsia and its complications.

Twin pregnancy, fetal reduction and the 'all or nothing problem'

Fetal reduction is the practice of reducing the number of fetuses in a multiple pregnancy, such as quadruplets, to a twin or singleton pregnancy. Use of assisted reproductive technologies increases the likelihood of multiple pregnancies, and many fetal reductions are done after in vitro fertilisation and embryo transfer, either because of social or health-related reasons. In this paper, I apply Joe Horton's all or nothing problem to the ethics of fetal reduction in the case of a twin pregnancy. I argue that in the case of a twin pregnancy, there are two intuitively plausible claims: (1) abortion is morally permissible, and (2) it is morally wrong to abort just one of the fetuses. But since we should choose morally permissible acts rather than impermissible ones, the two claims lead to another highly implausible claim: the woman ought to abort both fetuses rather than only one. Yet, this does not seem right. A plausible moral theory cannot advocate such a pro-death view. Or can it? I suggest ways to solve this problem and draw implications for each solution.

Hypertensive disorders of pregnancy and neonatal outcomes in twin vs. singleton pregnancies after assisted reproductive technology

OBJECTIVE

Hypertensive disorders of pregnancy (HDP) are associated with an increased risk of adverse neonatal outcomes. Although twin pregnancies had a higher risk of developing HDP, it is not known whether HDP in twins will increase the risk of adverse neonatal outcomes. We aimed to assess whether this association differed in singleton and twin pregnancies in women who conceived with assisted reproductive technology (ART).

METHODS

We finally included 193,590 live births born via ART from the National Vital Statistics System (NVSS) for the years 2015-2019. We used Log-binomial regression to evaluate the associations between HDP and the risk of adverse neonatal outcomes in ART mothers.

RESULTS

Among 193,590 ART-treated mothers, there were 140,870 and 52,720 mothers who had singleton pregnancies and twin pregnancies, respectively. Those ART mothers with twin pregnancies had a higher rate of HDP than singleton pregnancies (20.5% vs. 11.0%). In singleton pregnancies, the risks of preterm birth [adjusted risk ratio (aRR)): 2.80, 95% CI 2.67-2.93], low birth weight (aRR: 2.80, 95% CI 2.67-2.93), small for gestational age (aRR: 1.41, 95% CI 1.34-1.49), 5 min Apgar <7 (aRR: 1.66, 95% CI 1.50-1.83) and cesarean section (aRR: 1.23, 95% CI 1.21-1.25) were significantly higher in HDP mothers than in non-HDP mothers respectively. However, in contrast to singleton pregnancies, these associations were weak or reversed in twin pregnancies, after adjusting for confounding factors.

CONCLUSION

In ART-treated women, although twin pregnancies had a higher HDP rate, the risk of adverse neonatal outcomes associated with HDP was lower than that of singletons.

Evaluation of clinical parameters as predictors of monozygotic twins after single frozen embryo transfer

Objective

To determine if recent evolutions in laboratory protocols, including the increased use of natural cycles and the use of a hyaluronan-containing transfer medium, affected the rate of monozygotic twin (MZT) pregnancies after single frozen embryo transfer (FET).

Design

Retrospective cohort study.

Setting

Urban university-based fertility center.

Patients

Patients who underwent single FET between January 2016 and December 2018 resulting in an intrauterine pregnancy.

Interventions

Transition to a transfer protocol with a hyaluronan-containing transfer medium in July 2017.

Main Outcome Measures

Number of MZT pregnancies.

Results

There were 1,619 cycles that met the inclusion criteria and 31 (1.9%) resulted in MZT pregnancies. A hyaluronan-containing transfer medium was used in 875 (54.1%) cycles. Programmed cycles were used for 1,385 (85.5%) FETs and 234 (14.5%) cycles were natural. The mean age at FET, oocyte age, endometrial echo thickness, inner cell mass grade, trophectoderm grade, expansion, and day of blastocyst vitrification were similar between the groups. The use of a hyaluronan-containing transfer medium resulted in fewer MZTs. After controlling potential confounders with a multivariate regression, the use of the hyaluronan-containing medium still resulted in fewer MZTs. Monozygotic twins were colinear with preimplantation genetic testing (PGT), so PGT was excluded as a variable in our regression. A regression of PGT only cycles showed that the use of the hyaluronan-containing medium was still associated with a reduction in MZT pregnancies.

Conclusions

The use of a hyaluronan-containing transfer medium was associated with a lower rate of MZTs. Other clinical parameters, including cycle type, were not associated with changes in the number of MZTs. The use of PGT needs to be further investigated as a risk factor for MZTs.

Prediction of twin pregnancy preeclampsia based on clinical risk factors, early pregnancy serum markers, and uterine artery pulsatility index

Objectives:

To investigate whether a combination of clinical risk factors, early pregnancy serum markers, and uterine artery pulsatility index (UTPI) can be used to predict twin preeclampsia (PE).

Methods:

This case control study included women with twin pregnancies who had undergone obstetrics treatments and gave birth at the Huzhou Maternity and Child Health Care Hospital from October 2018 to November 2020. Patients with PE comprised study group, and patients without PE comprised control group based on selection criteria and a 1:1 ratio. Statistical analysis was performed using clinical risk factors, early pregnancy serum markers, and UTPIs, and the area under the receiver operating curve (AUC. Sensitivity, and the specificity of different combinations of these variables were calculated to predict PE in women with twin pregnancy.

Results:

Logistic regression analysis revealed four independent predictors for the onset of PE during twin pregnancies: first delivery (OR, 7.51; P=0.045), conception method (OR, 7.11; P=0.036), β-HCG level (per SD OR, 2.73; P=0.026), and UTPI (OR, 0.17; P=0.043). First-delivery and IVF pregnancy methods both lead to a 7-fold increase in the PE risk during twin pregnancies. Every one sigma (standard deviation) increase in the β-HCG level led to a 2.73-fold increase in the PE risk. Every UTPI increment by 1.0 reduces the risk of PE by 83%. The prediction efficiencies were based on an AUC of 0.837, a sensitivity of 69%, and a specificity of 92% for the clinical risk factors; an AUC of 0.800, a sensitivity of 81%, and specificity of 78% for the β-HCG level, and an AUC of 0.814, a sensitivity of 88%, and a specificity of 65% for the UTPI. AUC was 0.928, sensitivity 85%, and a specificity 88% after applying the three types of indicators together for prediction.

Conclusions:

By combining early pregnancy serum markers (β-HCG), and UTPI, the predictive value for PE during twin pregnancy is improved together with its sensitivity and specificity.