Prevalence, placenta development, and perinatal outcomes of women with hypertensive disorders of pregnancy at Komfo Anokye Teaching Hospital

BACKGROUND

One of the most common medical problems associated with pregnancy is hypertension. Hypertensive disorders of pregnancy (HDP), which has been attributable to abnormal placentation may have adverse effects on both mother and foetus if left unchecked. The objective of this study was to determine the prevalence of this condition and its effect on placental morphology as well as maternal and perinatal outcomes.

MATERIALS AND METHODS

This was a prospective case-control study, conducted at Komfo Anokye Teaching Hospital (KATH), Ghana between February 2018 and July 2018. The progression of pregnancy in normotensive and hypertensive pregnant women, and the eventual perinatal outcomes were closely followed. Statistical analysis was performed using IMB-SPSS version 23. Associations were considered significant at p values of ≤ 0.05.

RESULTS

From a total of 214 deliveries recorded during the period of study, 84 (39.25%) were hypertensives. Forty four (52%) of the hypertensives had preeclampsia, 28 (33.3%) had gestational hypertension, 6 (7.1%) had eclampsia, 4 (4.8%) had chronic hypertension, and 2 (2.4%) had preeclampsia superimposed on chronic hypertension. The frequency of placental haematoma, placental infarction, and placental calcification in the normotensives were significantly (p = 0.001) lower than that of the hypertensives. The mean placental weight (p = 0.01), placental volume (p = 0.001), placental diameter (p = 0.03), and placental thickness (p = 0.001) of the normotensives were significantly higher than those of the hypertensives. The number of normotensives in whom labour was induced, who had their babies delivered by caesarean section, and who were admitted after they had given birth were significantly (p = 0.001) lower than that of hypertensives who underwent similar procedures. No stillbirths were recorded in the normotensives compared with four in the hypertensives. The number of babies delivered to the normotensives who were admitted to the NICU was significantly (p = 0.001) lower than those delivered by hypertensives.

CONCLUSION

There was a high prevalence of hypertensive disorders of pregnancy in the study site. Pregnant women who developed HDP are at a risk of developing placental abnormalities that adversely affected perinatal outcomes. These adverse effects can be curtailed by embarking on a vigorous health education drive.

Placental morphometry in hypertensive disorders of pregnancy and its relationship with birth weight in a Latin American population

OBJECTIVE

To assess the placental morphometry in pregnancies with hypertensive disorders of pregnancy (HDP) and its relationship with birth weight (BW).

STUDY DESIGN

Cohort study of placental morphometry and fetal outcomes of 954 pregnancies at a university hospital in Ribeirão Preto, São Paulo, Brazil, in 2010. HDP categories were: chronic (CH), gestational (GH), preeclampsia (PRE) and pre-eclampsia superimposed on chronic hypertension (CH + PRE). Associations between BW and placental measures (PM) in pregnancies were evaluated by multiple linear regression analyses.

MAIN OUTCOME MEASURES (PM)

Placental weight (PW, g), largest and smallest diameters (cm), thickness (cm), eccentricity, area (cm²), volume (cm³), BW/PW ratio and PW/BW ratio (efficiency).

RESULTS

The frequencies of each HDP categories were 6.5% CH; 7.6% GH; 6.1% PRE, and 2.0% CH + PRE. PW, largest and smallest diameters, area and BW/PW ratio were statistically different between HDP and the normotensive group, with the lowest values for CH + PRE; the remaining measures showed no difference. BW was lower in HDP than in the normotensive group (p = 0.016). BW and PW were highly correlated in the presence of HDP (r = 0.79, p < 0.001). Sixty-seven percent of BW variability was accounted for PM (p < 0.001), and increased to 81% when maternal variables, gestational age and sex were added (p < 0.001).

CONCLUSIONS

Hypertensive disorders of pregnancy significantly influence the growth of both the placenta and the fetus. PM explain 67% of BW variability, and CH + PRE was the category with the strongest association to the results.

Preeclampsia: Syndrome or Disease?

The focus on disease mechanisms underlying the hypertension and proteinuria defining preeclampsia has increased knowledge of the pathophysiology yet we lack both therapy and predictors. We propose this is in part due to the fact that diagnostic findings identify a "preeclampsia syndrome" but do not necessarily indicate the most important pathophysiology nor if organs are involved as cause or consequence. The increased risk for later life cardiovascular disease in women who develop preeclampsia suggests the stress test of pregnancy exposes pre-existing subclinical vascular disease. The dogma that inadequate trophoblast invasion and ischemia/reperfusion injury to the placenta is "the" cause of preeclampsia is more relevant to early onset preeclampsia (<34 weeks). There is much less evidence for defective placentation in late onset preeclampsia where maternal constitutive factors or susceptibility to vascular damage is more relevant. The contribution of differing disease phenotypes to the syndrome may explain the inability of biomarker studies to identify all preeclampsia. Identification of phenotypes will require large amounts of prospective clinical data and biospecimens, collected in a harmonized manner with analysis in an unbiased discovery approach.

Endoglin in HIV-associated preeclamptic placentae

OBJECTIVE

To examine the placental immunoexpression of endoglin (Eng), in HIV-negative and HIV-positive normotensive (N- and N+) and preeclamptic (P- and P+) pregnancies at term, using immunohistochemistry and immunoelectron microscopy.

RESULTS

Strong Eng immunoreactivity was observed within endothelial cells, syncytio- and cyto-trophoblast cell populations. All extravillous trophoblast cells were immunopositive for Eng. Subcellularly, gold particles were immunolocalised within the endoplasmic reticulum, and mitochondria. Immunoexpression of Eng differed significantly between exchange (p = 0.02) and conducting villi (p < 0.001). A higher Eng immunoexpression was observed in both villi types of the preeclamptic compared to normotensive groups. Irrespective of pregnancy type (normotensive versus PE), there was no significant effect of HIV status on Eng immunoexpression within the exchange and conducting villi.

CONCLUSION

The immunostaining of Eng within the endothelial cells, syncytio-, cyto- and extravillous trophoblast cell populations of HIV-associated preeclamptic placentae is novel. Endoglin and its soluble component remains an area for dynamic placental exploration in preeclampsia development.

Comparison of 2-D and 3-D estimates of placental volume in early pregnancy

Ultrasound estimation of placental volume (PlaV) between 11 and 13 wk has been proposed as part of a screening test for small-for-gestational-age babies. A semi-automated 3-D technique, validated against the gold standard of manual delineation, has been found at this stage of gestation to predict small-for-gestational-age at term. Recently, when used in the third trimester, an estimate obtained using a 2-D technique was found to correlate with placental weight at delivery. Given its greater simplicity, the 2-D technique might be more useful as part of an early screening test. We investigated if the two techniques produced similar results when used in the first trimester. The correlation between PlaV values calculated by the two different techniques was assessed in 139 first-trimester placentas. The agreement on PlaV and derived "standardized placental volume," a dimensionless index correcting for gestational age, was explored with the Mann-Whitney test and Bland-Altman plots. Placentas were categorized into five different shape subtypes, and a subgroup analysis was performed. Agreement was poor for both PlaV and standardized PlaV (p < 0.001 and p < 0.001), with the 2-D technique yielding larger estimates for both indices compared with the 3-D method. The mean difference in standardized PlaV values between the two methods was 0.007 (95% confidence interval: 0.006-0.009). The best agreement was found for regular rectangle-shaped placentas (p = 0.438 and p = 0.408). The poor correlation between the 2-D and 3-D techniques may result from the heterogeneity of placental morphology at this stage of gestation. In early gestation, the simpler 2-D estimates of PlaV do not correlate strongly with those obtained with the validated 3-D technique.

Maternal imbalance between pro-angiogenic and anti-angiogenic factors in HIV-infected women with pre-eclampsia

Abstract

Angiogenic imbalance contributes to the development of preeclampsia. We evaluated the protein expression of the proangiogenic placental growth factor (PlGF) and transforming growth factor beta 1 (TGF-β₁) compared with the anti-angiogenic soluble fms-like tyrosine kinase receptor (sFlt1) and soluble endoglin (sEng) in HIV-infected normotensive and pre-eclamptic pregnancies.

Blood was obtained from 110 pregnant women, enrolled in four groups, namely, HIV-negative normotensives (27); HIV-positive normotensives (31); HIV-negative pre-eclamptics (27) and HIV-positive pre-eclamptics (25), and was used to measure PlGF, TGF-β1, sFlt1 and sEng levels.

Increased sFlt1 and sEng levels were associated with the pre-eclamptics (HIV negative and positive) compared with their counterparts. Decreased PlGF levels were observed between the HIV-negative pre-eclamptics versus HIV-negative normotensives, but levels differed significantly (p = 0.02) among the normotensives (HIV negative and positive). TGF-β₁ remained unchanged across all groups. Higher sEng/TGF-β₁ ratios were associated with the pre-eclamptics (HIV negative and positive) compared with their counterparts. This study demonstrated increased sFlt1 and sEng levels in pre-eclamptic compared with normotensive pregnancies, irrespective of the HIV status.

Risk factors for high and low placental weight

BACKGROUND

Placental weight is an independent predictor of adverse perinatal outcome. However, risk factors for high and low placental weight are poorly understood. The objective of this study was to identify maternal, placental, and umbilical cord determinants of placental weight, before and after accounting for birthweight.

METHODS

This cohort study of 87,600 singleton births at the Royal Victoria Hospital in Montreal, Canada assessed the relationship between maternal, placental, and umbilical cord characteristics and placental weight (standardised for sex and gestational age). We separately examined risk factors for high (z-score >+1) and low (z-score <-1) placental weight. Multivariable logistic regression was used to study associations after adjusting for confounders and further adjusting for birthweight.

RESULTS

Chronic hypertension was associated with low placental weight {relative risk (RR) 2.1 [95% confidence interval (CI) 1.8, 2.4] and 1.8 [95% CI 1.5, 2.1] before and after accounting for birthweight}, while pre-eclampsia was associated with low placenta weight before, but not after adjustment for birthweight. Anaemia and gestational diabetes were linked with high placental weight (RRs 1.2-1.4, respectively) before and after adjustment for birthweight, while smoking was linked with high placental weight only after adjustment for birthweight (RR 1.4 [95% CI 1.3, 1.5]). Placental and cord determinants of high placental weight included chorioamnionitis, chorangioma/chorangiosis, circumvallate placenta, marginal cord insertion, and other cord abnormalities.

CONCLUSIONS

The broad range of risk factors for high placental weight suggests multiple aetiologic pathways. Future work should seek to understand the pathways by which the placenta adapts to unfavourable intrauterine conditions, which may provide insights into potential therapies.

The interplay of human chorionic gonadotropin (hCG) with basic fibroblast growth factor and adipokines on angiogenesis in vitro

INTRODUCTION

Human chorionic gonadotropin (hCG) is suggested to regulate placental angiogenesis, however, its role is incompletely understood. hCG may directly stimulate angiogenesis or influence the effect of other angiogenic factors. We examined the effect of hCG and the interplay of hCG with basic fibroblast growth factor (bFGF) and with various adipokines on proliferation of vascular endothelial cells in vitro.

METHODS

Human umbilical vein endothelial cells (HUVEC) were incubated for 2 days with combinations of hCG, bFGF, leptin, resistin, adiponectin, IL6 and TNFα. Incorporation of radiolabelled thymidine was used to assess cell proliferation. Immunofluorescence and flow cytometry were used to examine activation of p44/42 mitogen-activated kinase (MAPK).

RESULTS

hCG induced proliferation of HUVEC alone and in combination with bFGF. Cells exposed to both hCG and bFGF displayed increased activation of p44/42 MAPK as compared to hCG or bFGF alone. Increased HUVEC proliferation was observed in the presence of increasing concentrations of leptin, resistin, adiponectin, and IL6, whereas HUVEC proliferation decreased in the presence of TNFα. hCG in combination with leptin, resistin, adiponectin or IL6 stimulated HUVEC proliferation beyond the effect of hCG alone.

DISCUSSION

An interplay of hCG with adipose tissue-derived factors with angiogenic properties is plausible. Thus, maternal obesity may affect placental angiogenesis in pregnancy.

CONCLUSIONS

hCG may directly stimulate angiogenesis. Also, hCG may indirectly stimulate angiogenesis through interplay with bFGF and adipokines.

Placental maturity, hypertensive disorders of pregnancy and birth weight

OBJECTIVES

To compare maturity of placentas from women with hypertensive disorders with those from normotensive pregnancies and to determine the relationship between placental maturity (PM) and the diagnosis of small-for-gestational-age (SGA) in the newborns.

MATERIALS AND METHODS

We examined placental stained specimens from women with normotensive pregnancies (n = 100), diagnosis of gestational hypertension (n = 38), mild (n = 10), or severe preeclampsia (n = 34) in an optical microscope. Placental Maturity Index (PMI) was calculated as the number of vasculo-syncytial membranes (VSM) in 1 mm(2) divided by VSM thickness (µm). Hypermaturity was defined as >90th percentile of the PMI from placentas of normotensive pregnancies. Newborns were classified as SGA, adequate-for-gestational-age (AGA) or large-for-gestational-age (<10th, 10-90th, and >90th percentile from weight for gestational age reference tables, respectively).

RESULTS

PMI in preeclamptic women (taking together mild and severe preeclampsia, PMI = 43.4 ± 1.6) was significantly higher than in normotensive women (PMI = 36 ± 2, p = 0.045). Hypermaturity was more frequent (p < 0.05) in placentas from women with preeclampsia than in those from normotensive women only in preterm pregnancies (<37 weeks), but not in those at term (p = 0.41). The frequency of hypermaturity in placentas from women with gestational hypertension was not statistically different than in normotensive women. Hypermaturity was also more frequent in placentas from SGA (OR = 2.63, p < 0.05) than in AGA newborns.

CONCLUSION

The PMI was increased in preeclampsia, but not in gestational hypertension. Placental hypermaturity was also associated with the diagnosis of SGA in newborns. PM might have a role in the relationship between maternal factors and SGA.

Is hyperemesis gravidarum associated with placental weight and the placental weight-to-birth weight ratio? A population-based Norwegian cohort study

INTRODUCTION

Studies have suggested a link between placental weight, placental weight-to-birth weight ratio (PW/BW) and adult health. Hyperemesis gravidarum (HG) may also have implications for adult health. No studies on HG and placental characteristics have been identified. We therefore explored the relationship between HG, placental weight and the PW/BW-ratio in a population-based cohort.

METHODS

Singleton births to primiparous women between 1999 and 2009 with data on HG, placental weight and birth weight in the Medical Birth Registry of Norway (MBRN) comprised the study base (n = 200,390). HG was defined through ICD-10 code 021.0, 021.1 and 021.9. Gender and gestational age specific percentile curves for placenta weight and PW/BW ratio were used to define those below the 10th and above the 90th percentile of both outcomes. Associations between HG and dichotomous outcomes were studied by multiple logistic regression. Multiple linear regression was applied to study placental weight as a continuous variable. Male and female offspring were analyzed separately.

RESULTS

The prevalence of HG was 1.2%. Women with HG and female offspring had significantly higher risk of a PW/BW-ratio above the 90th percentile (OR = 1.17, 95% CI: 1.03-1.34). HG and PW/BW-ratio below the 10th percentile were inversely associated (OR = 0.70, 95% CI: 0.56-0.89). For male offspring no association was observed for HG and PW/BW-ratio below the 10th or above the 90th percentile.

DISCUSSION/CONCLUSIONS

We observed positive associations between HG and high PW/BW ratio limited to female offspring only. The high PW/BW-ratio suggests that there may be a possible link between HG and adult health.

Soluble fms-like tyrosine kinase-1 and soluble endoglin in HIV-associated preeclampsia

OBJECTIVE

Preeclampsia is characterized by endothelial dysfunction combined with increased concentrations of sFlt1, which antagonizes the biological effects of VEGF and PlGF, and of sEng, which antagonizes TGFβ1. This angiogenic imbalance may have a role in its etiology. This study evaluated the expression of VEGF, PlGF, sFlt1 and sEng amongst third trimester pregnancies in women with HIV-associated pre-eclampsia.

METHOD

Serum and placental tissue were obtained from 76 pregnancies in women who were normotensive and HIV negative (N-) or positive (N+), and in women who were pre-eclamptic and HIV negative (P-) or positive (P+). The serum and placental samples were quantitatively evaluated using ELISAs and RT-PCR respectively.

RESULTS

Placental sFlt1 expression differed significantly between the N- and P- groups (p=0.001). Similarly, sEng expression differed between the N- and P- groups (p=0.001). No significant effect was shown between HIV status and pregnancy. Serum sFlt1 (p=0.02) and sEng (p=0.001) were up-regulated in the P- compared to the N- groups. Similarly, no significant effect was shown between HIV status and pregnancy. Both VEGF and PlGF did not differ significantly between groups. Notably, sEng expression was elevated in both placenta and serum, whilst placental sFlt1 differed from serum. A weak but significant correlation between serum and placental concentration for sFlt1, sEng and PlGF (r=0.26, p=0.031; r=0.42, p<0.001 and r=-0.3, p=0.014) was observed.

CONCLUSIONS

This novel study demonstrates an up-regulation of serum sFlt1 and sEng in preeclamptic compared to normotensive groups irrespective of the HIV status of the pregnancy. This implicates a contributory role of sFlt1 and sEng in preeclampsia development. The serum reduction of sFlt1 and sEng within the HIV positive compared to HIV negative cohorts may imply a neutralization of the immune hyperreactivity of preeclampsia.

Elsevier Trophoblast Research Award Lecture: Searching for an early pregnancy 3-D morphometric ultrasound marker to predict fetal growth restriction

Fetal growth restriction (FGR) is a major cause of perinatal morbidity and mortality, even in term babies. An effective screening test to identify pregnancies at risk of FGR, leading to increased antenatal surveillance with timely delivery, could decrease perinatal mortality and morbidity. Placental volume, measured with commercially available packages and a novel, semi-automated technique, has been shown to predict small for gestational age babies. Placental morphology measured in 2-D in the second trimester and ex-vivo post delivery, correlates with FGR. This has also been investigated using 2-D estimates of diameter and site of cord insertion obtained using the Virtual Organ Computer-aided AnaLysis (VOCAL) software. Data is presented describing a pilot study of a novel 3-D method for defining compactness of placental shape. We prospectively recruited women with a singleton pregnancy and BMI of <35. A 3-D ultrasound scan was performed between 11 and 13 + 6 weeks' gestation. The placental volume, total placental surface area and the area of the utero-placental interface were calculated using our validated technique. From these we generated dimensionless indices including sphericity (ψ), standardised placental volume (sPlaV) and standardised functional area (sFA) using Buckingham π theorem. The marker for FGR used was small for gestational age, defined as <10th customised birth weight centile (cSGA). Regression analysis examined which of the morphometric indices were independent predictors of cSGA. Data were collected for 143 women, 20 had cSGA babies. Only sPlaV and sFA were significantly correlated to birth weight (p < 0.001). Regression demonstrated all dimensionless indices were inter-dependent co-factors. ROC curves showed no advantage for using sFA over the simpler sPlaV. The generated placental indices are not independent of placental volume this early in gestation. It is hoped that another placental ultrasound marker based on vascularity can improve the prediction of FGR offered by a model based on placental volume.

Plasma kisspeptin levels in pregnancies with diabetes and hypertensive disease as a potential marker of placental dysfunction and adverse perinatal outcome

BACKGROUND

The aim of this study was to prospectively evaluate plasma kisspeptin levels in 129 singleton pregnancies with diabetes [pregestational insulin-dependent diabetes mellitus (type 1) and gestational diabetes (GD)] and hypertensive disease [chronic hypertension (CH), gestational hypertension, and preeclampsia (PE)] as a potential marker of placental dysfunction and adverse perinatal outcome.

STUDY DESIGN

Kisspeptin levels were evaluated in the first, second, and third trimesters in patients with type 1 diabetes (16 patients), H (22), and healthy control (25) and in the second and third trimesters in patients with GD (20), gestational hypertension (18), and PE (28). Maternal kisspeptin levels were correlated with pregnancy outcome, parameters of fetoplacental circulation, ultrasound-detected abnormalities of placental morphology, and placental weight at delivery.

RESULTS

In pregnancies with type 1 diabetes and H, mean kisspeptin levels were significantly lower compared with the control group (p<0.001 in the first and second trimesters and p<0.05 in the third trimester). Decreased plasma kisspeptin levels in the second and third trimesters were found in patients with GD (p<0.001 in the second and third trimesters) and PE (p<0.001 in the second trimester and p<0.05 in the third trimester). In patients with PE and placental dysfunction, low kisspeptin levels in the third trimester were associated with adverse perinatal outcome.

CONCLUSIONS

Our study demonstrates reduced kisspeptin levels in pregnancies with diabetes, H, PE, and placental dysfunction. In patients with PE and placental dysfunction, decreased kisspeptin levels were associated with adverse perinatal outcome. Larger studies are needed to investigate the role of kisspeptin as a potential marker of placental dysfunction and adverse perinatal outcome.

Increased endoplasmic reticulum stress in decidual tissue from pregnancies complicated by fetal growth restriction with and without pre-eclampsia

OBJECTIVES

Endoplasmic reticulum (ER) stress has been implicated in both pre-eclampsia (PE) and fetal growth restriction (FGR), and is characterised by activation of three signalling branches: 1) PERK-pEIF2α, 2) ATF6 and 3) splicing of XBP1(U) into XBP1(S). To evaluate the contribution of ER stress in the pathogenesis of PE relative to FGR, we compared levels of ER stress markers in decidual tissue from pregnancies complicated by PE and/or FGR.

STUDY DESIGN

Whole-genome transcriptional profiling was performed on decidual tissue from women with PE (n = 13), FGR (n = 9), PE+FGR (n = 24) and controls (n = 58), and used for pathway and targeted transcriptional analyses of ER stress markers. The expression and cellular localisation of ER stress markers was assesses by Western blot and immunofluorescence analyses.

RESULTS

Increased ER stress was observed in FGR and PE+FGR, including both the PERK-pEIF2α and ATF6 signalling branches, whereas ER stress was less evident in isolated PE. However, these cases demonstrated elevated levels of XBP1(U) protein. ATF6 and XBP1 immunoreactivity was detected in most (>80%) extravillous trophoblasts, decidual cells and macrophages. No difference in the proportion of immunopositive cells or staining pattern was observed between study groups.

CONCLUSIONS

Increased PERK-pEIF2α and ATF6 signalling have been associated with decreased cellular proliferation and may contribute to the impaired placental growth characterising pregnancies with FGR and PE+FGR. XBP1(U) has been proposed as a negative regulator of ER stress, and increased levels in PE may reflect a protective mechanism against the detrimental effects of ER stress.

Placental weight and excess postpartum haemorrhage: a population study of 308,717 pregnancies

OBJECTIVE

To investigate whether placental weight may be positively associated with the prevalence of excess postpartum haemorrhage because large placentas have large surface areas.

DESIGN

Registry-based cross-sectional study.

SETTING

Population study.

POPULATION

All singleton deliveries after 21 weeks of gestation in Norway during 1999-2004 (n = 308,717).

METHODS

Data were obtained from the Medical Birth Registry of Norway, which is based on compulsory notification of births by the midwife or doctor in charge of the delivery.

MAIN OUTCOME MEASURE

Excess postpartum haemorrhage was defined as bleeding of 500 ml or more within 2 hours of delivery.

RESULTS

There was a gradual increase in the prevalence of excess postpartum haemorrhage with increasing placental weight (test for trend, P < 0.05). Having a placenta of 1100 g or more was associated with 2.5 times (odds ratio 2.54, 95% CI 2.31-2.79) higher prevalence than having a placenta of 300-499 g, after adjustment for offspring birthweight, parity, caesarean section and placenta-related and delivery-related complications. A large placenta relative to birthweight was also associated with higher prevalence of excess postpartum haemorrhage.

CONCLUSION

The size of the placental surface may explain the positive association of placental weight with the prevalence of postpartum haemorrhage. In pregnancies with a large placenta relative to offspring birthweight, other factors that enhance bleeding may also play a role.