Pregnancy complications and maternal risk of ischaemic heart disease: a retrospective cohort study of 129,290 births

Free fatty acid profiles in preeclampsia

Preeclampsia has many characteristics similar to the metabolic syndrome. One of these is aberrant lipid metabolism. We studied free fatty acid (FFA) profiles at baseline and after oral glucose load in 21 preeclamptic and 11 normotensive pregnant women. Insulin sensitivity was measured by intravenous glucose tolerance test. We found that serum total FFA concentrations at baseline were 67% higher in preeclamptic than in normotensive pregnancies (P=0.0002). The difference between the two groups was largest in the concentrations of oleic (75%), linoleic (129%) and arachidonic (315%) acids. Oral intake of glucose suppressed total FFA in preeclamptic women by 40% (95% CI 32.1-46.1%, P<0.0001) but only 24% in control women (95% CI 0.01-42.0%, P=0.045). Insulin sensitivity, which in preeclamptic women was 37% lower (P=0.009), was unrelated to total or any individual FFA concentration. We concluded that preeclamptic women have higher circulating FFA concentrations, which despite insulin resistance are suppressed by oral glucose loading.

Primary atherothrombotic occlusive vascular events in premenopausal women with history of adverse pregnancy outcome

OBJECTIVE

To determine if adverse pregnancy outcomes are associated with atherothrombotic occlusive vascular disease (AOVD) in premenopausal women.

DESIGN

Retrospective matched case-control study.

SETTING

Tertiary, university-affiliated medical center.

POPULATION

Women aged less than 50 years treated for an AOVD (primary cerebrovascular, myocardial, or peripheral arterial ischemic event) from 1995 to 2004.

METHOD

The files were reviewed for classical risk factors for AOVD and complications of pregnancy (abortions, pregnancy-induced hypertension, preeclampsia, gestational diabetes, intrauterine growth restriction (IUGR), fetal loss and preterm delivery). Findings were compared with healthy women matched for age and body mass index.

MAIN OUTCOME MEASURES

Past pregnancy complications in premenopausal women with AOVD.

RESULTS

Of the 101 women with AOVD, 53 had a myocardial ischemic event, 33 a cerebrovascular event, and 15 a peripheral ischemic arterial event. On multivariate analysis, IUGR (OR 8.41, 95% CI 2.36-29.9, p=0.001) and more than one pregnancy complication (OR 13.7, 95% CI 1.56-120, p=0.02) were found to be independent significant variables associated with AOVD.

CONCLUSION

IUGR and composite pregnancy complications are independent significant variables associated with AOVD in premenopausal period. Pregnancy outcome might serve as a means to identify patients who may require increased medical surveillance and preventive measures for later vascular disease.

Role of monoamine oxidases in the exaggerated 5-hydroxytryptamine-induced tension development of human isolated preeclamptic umbilical artery

We investigated the role(s) of monoamine oxidases (MAOs) on the altered 5-hydroxytryptamine (5-HT, serotonin)-induced tension development of the isolated umbilical artery of preeclamptic pregnancy of Chinese women. An enhanced 5-HT-induced tension development of the umbilical artery of preeclamptic pregnancy was observed when compared with that of normal pregnancy. The enhanced component of 5-HT-induced tension development was eradicated by clorgyline (a MAO-A inhibitor). Blockade of eNOS (endothelial isoform nitric oxide synthase) (N(omega)-nitro-L-arginine methyl ester), 5-HT transporter (citalopram), 5-HT receptor subtypes (5HT2B, SB 204741; 5-HT2C, RS 102221; 5-HT7, SB 269970), and endothelium denudation of the umbilical artery of normal pregnancy mimicked the enhanced 5-HT-induced tension development as observed in the preeclamptic tissues. In contrast, no apparent changes in 5-HT-induced tension development of the umbilical artery of preeclamptic pregnancy were observed with the same pharmacological manipulations. A decreased protein expression levels of MAO-A and eNOS (no iNOS and MAO-B expression was detected) and no change in caveolin-1 and 5-HT transporter expression were demonstrated in the umbilical artery (endothelium intact) lysate of preeclamptic pregnancy, compared to that of the umbilical artery of normal pregnancy. Thus, in the umbilical artery of preeclamptic pregnancy, a decrease of MAO-A and eNOS protein expression levels are probably associated with, or responsible for, the exaggerated 5-HT-induced tension development.

Maternal cardiovascular disease risk in relation to the number of offspring born small for gestational age: national, multi-generational study of 2.7 million births

AIM

To investigate the risk of small for gestational age (SGA) births in relation to maternal history of cardiovascular disease (CVD) across two generations and additionally to analyse maternal CVD risk based on number of SGA offspring.

METHODS

We used register data from 1.4 million women and 2.7 million offspring. The outcome measures were risk of being SGA in relation to maternal total CVD (n = 10 436) across two generations, as well as risk of CVD in mothers in relation to the number of their SGA offspring, stratified by educational level.

RESULTS

Compared to no family history of CVD (reference) the hazard ratio (HR) for being SGA in female offspring was 1.11 (95% confidence interval (CI) 1.09-1.13) for a positive maternal history of CVD. The highest risk was shown in daughters when both the mother and the grandmother had a history of CVD (HR 1.32, 95% CI 1.24-1.39). There was a stepwise increased risk of CVD events in mothers in relation to the number of their SGA offspring (HR 1.41-1.86) when 'no SGA offspring' was used as reference. The risk of CVD in relation to SGA status was increased in the least educated group (HR 2.7-5.0) compared to the group with the highest level of education with no SGA offspring.

CONCLUSION

The risk of SGA offspring and the risk of maternal CVD are mutually interdependent and both conditions increased in women with a low level of education.

Cardiopulmonary complications of pre-eclampsia

Pre-eclampsia affects 3 to 8% of all pregnancies. In the USA, pre-eclampsia remains a leading cause of maternal morbidity and mortality, comprising 17% of maternal deaths in advanced gestations in 1999. The pathophysiologic changes associated with pre-eclampsia can have a profound impact on the uteroplacental unit and fetal and neonatal outcome. Equally important are the adverse effects on the maternal hematologic, cardiovascular and pulmonary, neurologic, renal, and gastrointestinal system. This article aims to review complications of pre-eclampsia as they impact on the cardiovascular and pulmonary systems.

Insulin resistance in women with a history of severe pre-eclampsia

AIM

This study investigated whether post-partum insulin resistance existed in women with a history of severe pre-eclampsia.

METHODS

The euglycemic hyperinsulinemic clamp technique was used to assess insulin sensitivity at least 6 months after delivery in 13 women who had had severe pre-eclampsia and 26 age- and body mass index-matched controls who had had normal pregnancy.

RESULTS

The mean (+/-SD) durations after delivery were 2.6 +/- 1.6 years and 4.5 +/- 2.8 years in the pre-eclampsia and control groups, respectively. The systolic blood pressure was significantly higher in the pre-eclampsia group (118 +/- 11 mmHg vs 109 +/- 12 mmHg, P = 0.028). Although the body mass indices were not different among the groups (25.8 +/- 3.1 kg/m(2) vs 24.6 +/- 3.9 kg/m(2)), the waist and waist-to-hip ratio were significantly higher in the women with prior pre-eclampsia. The pre-eclampsia group had lower insulin sensitivity index than the controls (5.4 +/- 2.5 mg/kg/min/mU/L vs 8.1 +/- 4.0 mg/kg/min/mU/L, P = 0.036). Serum triglyceride levels were significantly higher in the pre-eclampsia group (153 +/- 74 mg/dL vs 82 +/- 37 mg/dL, P < 0.01). High-density lipoprotein-cholesterol levels tended to be lower in the pre-eclampsia group (42.1 +/- 9.7 mg/dL vs 48.2 +/- 9.6 mg/dL, P = 0.07).

CONCLUSION

Women with a history of severe pre-eclampsia had characteristics of metabolic syndrome and had lower insulin sensitivity compared with those who had had normal pregnancy. These may explain an increased risk of cardiovascular disease in women with pre-eclampsia.

Hypertensive pregnancy disorders and subsequent cardiovascular morbidity and type 2 diabetes mellitus in the mother

Minimal data exist concerning the relationship between hypertensive pregnancy disorders and various subsequent cardiovascular events and the effect of type 2 diabetes mellitus on these. In a registry-based cohort study, we identified women delivering in Denmark from 1978 to 2007 with a first singleton (n=782 287) and 2 first consecutive singleton deliveries (n=536 419). The exposures were gestational hypertension and mild and severe preeclampsia. We adjusted for preterm delivery, small for gestational age, placental abruption, and stillbirth and, in a second model, we also adjusted for the development of type 2 diabetes mellitus. The end points were subsequent hypertension, ischemic heart disease, congestive heart failure, thromboembolic event, stroke, and type 2 diabetes mellitus. The risk of subsequent hypertension was increased 5.31-fold (range: 4.90 to 5.75) after gestational hypertension, 3.61-fold (range: 3.43 to 3.80) after mild preeclampsia, and 6.07-fold (range: 5.45 to 6.77) after severe preeclampsia. The risk of subsequent type 2 diabetes mellitus was increased 3.12-fold (range: 2.63 to 3.70) after gestational hypertension and 3.68-fold (range: 3.04 to 4.46) after severe preeclampsia. Women having 2 pregnancies both complicated by preeclampsia had a 6.00-fold (range: 5.40 to 6.67) increased risk of subsequent hypertension compared with 2.70-fold (range: 2.51 to 2.90) for women having preeclampsia in their first pregnancy only and 4.34-fold (range: 3.98 to 4.74) for women having preeclampsia in their second pregnancy only. The risk of subsequent thromboembolism was 1.03-fold (range: 0.73 to 1.45), 1.53-fold (range: 1.32 to 1.77), and 1.91-fold (range: 1.35 to 2.70) increased after gestational hypertension and mild and severe preeclampsia, respectively. Thus, hypertensive pregnancy disorders are strongly associated with subsequent type 2 diabetes mellitus and hypertension, the latter independent of subsequent type 2 diabetes mellitus. The severity, parity, and recurrence of these hypertensive pregnancy disorders increase the risk of subsequent cardiovascular events.

Investigating the risk of hypertension shortly after pregnancies complicated by preeclampsia

OBJECTIVE

Women with a history of preeclampsia are at increased risk for long-term cardiovascular morbidity and mortality. This study assessed whether a pregnancy complicated by preeclampsia is associated with an increased prevalence of maternal hypertension and other cardiovascular risk factors shortly after delivery.

STUDY DESIGN

Seventy-nine cases and 140 controls that had been enrolled in a prospective case-control study were evaluated in this planned follow-up analysis. The presence of hypertension, diabetes and dyslipidemia were assessed by standardized questionnaire 6-13 months after delivery.

RESULTS

Women with preeclampsia were significantly more likely than controls to have hypertension (adjusted odds ratio, 13.92; 95% CI, 5.17-37.4; P < .001) after adjusting for confounders. Women with preterm preeclampsia also had an increased odds of hypertension (adjusted odds ratio, 18.31; 95% CI, 5.04-66.46; P < .001) compared with controls.

CONCLUSION

Pregnancy complications, such as preeclampsia, may provide opportunities to identify women at risk for cardiovascular morbidity years before the onset of disease, allowing a window for prevention and intervention.

Birth weight of offspring, maternal pre-pregnancy characteristics, and mortality of mothers: the Jerusalem perinatal study cohort

PURPOSE

To explore the association between birth weight in offspring, a marker of the intrauterine environment, and mortality in their mothers, taking into account maternal pre-pregnancy characteristics, including maternal body mass index (BMI), smoking, and socioeconomic status. Distinguishing the effects of offspring's birth weight and pre-pregnancy characteristics on maternal outcome may provide clues regarding mechanisms underlying the association between birth weight and maternal mortality.

METHODS

We studied long-term total mortality (average follow-up period, 29.1 years) in a population-based cohort of 13,185 mothers, aged 15 to 48 years at their offspring's birth, who delivered in West Jerusalem during 1974 through 1976.

RESULTS

Univariate and multivariate Cox-proportional hazard models used to estimate the hazard of overall mortality among mothers indicated a nonlinear relationship with birth weight of offspring when introduced into the models as a continuous variable, and a linear positive association with maternal pre-pregnancy BMI. Inclusion of maternal BMI and other pre-pregnancy characteristics in the model did not alter the association between offspring's birth weight and mothers' all-cause mortality. When birth weight was introduced as a categorical variable, higher mortality was observed among mothers who gave birth to babies with birth weight less than 2500 g (hazard ratio [HR] = 1.90; 95% confidence interval [95%CI], 1.23-2.94) as compared to mothers whose offspring had birth weight between 3000 and 3499 g. The HR for mothers who gave birth to babies with birth weight 4000 g or more was 1.30 (95%CI, 0.88-1.91).

CONCLUSIONS

Independent of pre-pregnancy maternal BMI and other characteristics, birth weight of offspring was associated with mortality in their mothers, suggesting that intrauterine metabolic events reflected by birth weight and not explained by maternal obesity, smoking, and socioeconomic status have remote consequences for maternal health. These findings underline the need to explore specific genetic and/or environmental mechanisms that account for these associations.

Body composition by dual-energy X-ray absorptiometry in women with previous pre-eclampsia or small-for-gestational-age offspring

OBJECTIVE

To investigate differences in body composition and fat distribution between women with previous pre-eclampsia or small-for-gestational-age (SGA) offspring and those with uncomplicated pregnancies.

DESIGN

Cohort study.

SETTING

Population-based study in a genetically isolated population in the southwest of the Netherlands.

POPULATION

Women after pregnancies complicated by pre-eclampsia (n=45), SGA offspring (n=53) and uncomplicated pregnancies (n=106).

METHODS

Women were compared for body composition and fat distribution variables, assessed by dual-energy X-ray absorptiometry (DXA) and anthropometrics at a mean follow-up time of 10.8 (SD +/- 5.9) years after pregnancy.

MAIN OUTCOME MEASURES

Total lean and fat mass, android fat mass, gynoid fat mass, android-to-gynoid fat ratio, waist and hip circumference, waist-to-hip ratio.

RESULTS

Women with previous pre-eclampsia compared with controls had higher mean total fat mass index (11.5 +/- 0.6 versus 9.7 +/- 0.4 kg/m(2); P = 0.03), lean mass index (15.8 +/- 0.3 versus 14.5 +/- 0.2 kg/m(2); P =0.001) and body mass index ([BMI]; 28.4 +/- 0.8 versus 25.4 +/- 0.5 kg/m(2); P = 0.005). Their waist circumferences (90.7 +/- 2.0 versus 78.5 +/- 1.3 cm; P < 0.001) and waist-to-hip ratios (0.86 +/- 0.01 versus 0.77 +/- 0.01; P < 0.001) were also higher as well as android fat mass (2.8 +/- 0.2 versus 2.1 +/- 0.1 kg; P = 0.01) and android-to-gynoid fat ratios (0.45 +/- 0.02 versus 0.39 +/- 0.01; P = 0.02). Mean total fat, lean and BMI was not significantly different between women with previous SGA offspring and controls, yet waist-to-hip ratios (0.83 +/- 0.01; P < 0.001) were higher. The observed differences in waist and hip circumference, waist-to-hip ratio and gynoid fat mass could not be attributed to differences in BMI.

CONCLUSION

Women with previous pre-eclampsia or SGA offspring pregnancies compared with those with uncomplicated pregnancies have a preferential fat accumulation in the abdominal over hip region, which may explain, at least partly, their increased cardiovascular risk.

Association of Remote Hypertension in Pregnancy With Coronary Artery Disease

Because hypertensive pregnancies have been associated with increased cardiovascular disease, we aimed to identify whether angiographically characterized coronary artery disease differed in women with previous normotensive pregnancies or hypertensive pregnancies (HPs). The study group included 217 parous women, aged 60.9±9.2 (SD) years, who required coronary angiography between January 2006 and December 2007, 36.8±9.9 and 28.8±10.5 years after their first and last pregnancy, respectively; 146 had normotensive pregnancies and 71 had ≥1 HP, according to a questionnaire including reproductive history and cardiovascular risks. Body mass index, smoking, and frequency of diabetes were similar in both groups. Chronic hypertension (93% versus 78%; P =0.007), hyperlipidemia (82% versus 69%; P =0.049), and premature familial cardiovascular disease (42% versus 20%; P =0.001) prevailed in HPs. Participants with HPs were younger (58.9±8.3 versus 61.9±9.6 years; P =0.025) than participants with normotensive pregnancies. Although 49% of all participants had hemodynamically significant coronary artery disease (≥70% stenosis), no differences were observed between groups in the number of stenotic arteries; however, their number increased by 28% and 22% over a 10-year period in HPs and normotensive pregnancies, respectively ( P =0.034). Multivariate analysis showed that HPs had a nonsignificant risk of having coronary artery disease (odds ratio: 1.21; 95% CI: 0.64 to 2.28), and being a current smoker (odds ratio: 4.13; 95% CI: 1.85 to 9.25), a diabetic (odds ratio: 2.29; 95% CI: 1.85 to 9.25), or having a family history of premature cardiovascular disease (odds ratio: 2.34; 95% CI: 1.17 to 2.39) significantly increased the risk of coronary artery disease. This study demonstrates that women with HPs have earlier coronary disease, probably related to intermediate cardiovascular risks that have a gestational expression.

Vasculopathic and thrombophilic risk factors for spontaneous preterm birth

BACKGROUND

Mothers who give birth to preterm infants are at increased risk of mortality from coronary heart disease and stroke, but the biological pathways underlying these associations have not been explored.

METHODS

We carried out a case-control study nested in a large (n = 5337) prospective, multicentre cohort. All cohort women had an interview, examination and venipuncture at 24-26 weeks. Frozen plasma samples in spontaneous preterm births (n = 207) and 444 term controls were analysed for plasma homocysteine, folate, cholesterol (total, low-density lipoprotein and high-density lipoprotein) and thrombin-antithrombin (TAT) complexes. DNA was extracted and analysed for seven gene polymorphisms involved in thrombophilia or folate or homocysteine metabolism. Fresh placentas were fixed, stained and blindly assessed for histologic evidence of infarction and decidual vasculopathy.

RESULTS

High (above the median) plasma homocysteine and HDL cholesterol were significantly and independently associated with the risk of spontaneous preterm birth [adjusted odds ratios (OR)s = 1.9 (95% 1.1-3.3) and 0.5 (0.3-0.9), respectively]. A higher proportion of women with high homocysteine concentrations had decidual vasculopathy [(13.0 vs 6.8%; OR = 1.9 (1.1-3.5)], although the positive association between decidual vasculopathy and preterm birth did not achieve statistical significance [OR = 1.5 (0.9-2.7)]. No significant associations were observed with the DNA polymorphisms or with plasma TAT or folate levels.

CONCLUSIONS

Similar vasculopathic risk factors may underlie preterm birth and adult coronary heart disease and stroke.

Pre-eclampsia is associated with increased risk of stroke in the adult offspring: the Helsinki birth cohort study

BACKGROUND AND PURPOSE

Women who develop pre-eclampsia in pregnancy are at increased risk of cardiovascular disease. The offspring from pregnancies complicated by pre-eclampsia have higher blood pressures during childhood, but little is known about their long-term health. We hypothesized that pre-eclampsia would lead to an increased risk of cardiovascular disease in the offspring.

METHODS

We traced 6410 babies born in Helsinki, Finland, from 1934 to 1944. We used the mothers' blood pressure levels and the presence of proteinuria during pregnancy to define pre-eclampsia and gestational hypertension without proteinuria according to modern criteria.

RESULTS

Two hundred eighty-four of the pregnancies were complicated by pre-eclampsia (120 with nonsevere and 164 with severe disease) and 1592 by gestational hypertension. The crude hazard ratio for all forms of stroke among people whose mothers had pre-eclampsia was 1.9 (1.2 to 3.0; P=0.01); among people whose mothers had gestational hypertension, it was 1.4 (1.0 to 1.8; P=0.03). There was no evidence that these pregnancy disorders were associated with coronary heart disease in the offspring. Pre-eclampsia, in particular severe disease, was associated with a reduced mean head circumference at birth, whereas gestational hypertension was associated with an increased head circumference in relation to body length.

CONCLUSIONS

People born after pregnancies complicated by pre-eclampsia or gestational hypertension are at increased risk of stroke. The underlying processes may include a local disorder of the blood vessels of the brain as a consequence of either reduced brain growth or impaired brain growth leading to "brain-sparing" responses in utero.

Vascular biology of preeclampsia

Preeclampsia, a pregnancy-specific syndrome characterized by hypertension, proteinuria and edema, resolves on delivery of the placenta. Normal pregnancy is itself characterized by systemic inflammation, oxidative stress and alterations in levels of angiogenic factors and vascular reactivity. This is exacerbated in preeclampsia with an associated breakdown of compensatory mechanisms, eventually leading to placental and vascular dysfunction. The underlying pathology of preeclampsia is thought to be a relatively hypoxic or ischemic placenta. Both the placenta and maternal vasculatures are major sources of reactive oxygen and nitrogen species which can interact to produce peroxynitrite a powerful prooxidant that covalently modifies proteins by nitration of tyrosine residues, to possibly alter vascular function in preeclampsia. The linkage between placental hypoxia and maternal vascular dysfunction has been proposed to be via placental syncytiotrophoblast basement membranes shed by the placenta or via angiogenic factors which include soluble flt1 and endoglin secreted by the placenta that bind vascular endothelial growth factor (VEGF) and placental growth factor (PIGF) in the maternal circulation. There is also abundant evidence of altered reactivity of the maternal and placental vasculature and of the altered production of autocoids in preeclampsia. The occurrence of preeclampsia is increased in women with preexisting vascular disease and confers a long-term risk for development of cardiovascular disease. The vascular stress test of pregnancy thus identifies those women with a previously unrecognized at risk vascular system and promotes the development of preeclampsia. Preexisting maternal vascular dysfunction intensified by placental factors is possibly responsible for the individual pathologies of preeclampsia.

Altered alanine aminotransferase and gamma-glutamyl transpeptidase in women with history of preeclampsia: association with waist-to-hip ratio and body mass index

OBJECTIVE

Preeclampsia (PE), mostly when associated with HELLP syndrome, together with acute fatty liver of pregnancy, are the main causes of severe hepatic failure in pregnancy. Despite the number of studies in pregnancies complicated with PE, there are a few studies that focused on the evaluation of the hepatic function of these women several years after delivery. In this way, we evaluated circulating levels of AST, ALT, gammaGT and CRP several years after preeclamptic pregnancy to verify if these parameters are altered.

METHODS

Eighty-nine women with previous PE and 60 women without medical complications were invited to the research centers. After the physical examination, blood was drawn for biochemical measurements. Plasma CRP levels and serum concentration of AST, ALT, gammaGT were measured by automated enzymatic assays.

RESULTS

Systolic and diastolic blood pressures were significantly higher in women with history of PE than in control group as well as BMI and waist-to-hip ratio. ALT and gammaGT were significantly higher in women with previous history of PE, whereas AST and CRP presented similar levels between the two groups. Data revealed statistically significant positive correlations between ALT and gammaGT with waist-to-hip ratio and BMI. Positive correlations were also found between BMI and AST and CRP.

CONCLUSION

It is possible that the increase in ALT and gammaGT levels is due to being overweight or through accumulation of visceral fat. Unaltered values of CRP suggest that the higher ALT and gammaGT values found in women with history of PE are not associated with inflammation.

High aldosterone-to-renin variants of CYP11B2 and pregnancy outcome

BACKGROUND

Increased aldosterone concentrations and volume expansion of normal pregnancies are hallmarks of normal pregnancies and blunted in pre-eclampsia. Accordingly, we hypothesized an active mineralocorticoid system to protect from pre-eclampsia.

METHODS

In pregnant women (normotensive n = 44; pre-eclamptic n = 48), blood pressure, urinary tetrahydro-aldosterone excretion and activating polymorphisms (SF-1 site and intron 2) of the aldosterone synthase gene (CYP11B2) were determined; 185 non-pregnant normotensive individuals served as control. Amino acid-changing polymorphisms of the DNA- and agonist-binding regions of the mineralocorticoid receptor were evaluated by RT-PCR, SSCP and sequencing.

RESULTS

Urinary tetrahydro-aldosterone excretion was reduced in pre-eclampsia as compared to normal pregnancy (P < 0.05). It inversely correlated with blood pressure (r = 0.99, P < 0.04). Homozygosity for activating CYP11B2 polymorphisms was preferably present in normotensive as compared to pre-eclamptic pregnancies, identified (intron 2, P = 0.005; SF-1 site, P = 0.016). Two mutant haplotypes decreased the risk of developing pre-eclampsia (RR 0.16; CI 0.05-0.54; P < 0.001). In contrast, intron 2 wild type predisposed to pre-eclampsia (P < 0.0015). No functional mineralocorticoid receptor mutant has been observed.

CONCLUSIONS

High aldosterone availability is associated with lower maternal blood pressure. In line with this observation, gain-of-function variants of the CYP11B2 reduce the risk of developing pre-eclampsia. Mutants of the mineralocorticoid receptor cannot explain the frequent syndrome of pre-eclampsia.

Maternal serum adiponectin multimers in preeclampsia

OBJECTIVE

Obesity, insulin resistance, and dyslipidemia are associated with preeclampsia. Recently, "adipose tissue failure", characterized by dysregulation of adipokine production, has been implicated in the pathophysiology of these metabolic complications. Adiponectin, an insulin-sensitizing, anti-atherogenic, anti-inflammatory and angiogenic adipokine, circulates in oligomeric complexes including: low-molecular-weight (LMW) trimers, medium-molecular-weight (MMW) hexamers and high-molecular-weight (HMW) isoforms. These multimers exert differential biological effects, and HMW to total adiponectin ratio (S(A)) has been reported to be a specific marker of adiponectin activity. The aim of this study was to determine whether preeclampsia is associated with changes in circulating adiponectin multimers.

STUDY DESIGN

This cross-sectional study included women with: 1) normal pregnancy (n=225); and 2) patients with mild preeclampsia (n=111). The study population was further stratified by first trimester BMI (normal weight <25 kg/m(2) vs. overweight/obese >or=25 kg/m(2)). Serum adiponectin multimers (total, HMW, MMW and LMW) concentrations were determined by ELISA. Non-parametric statistics were used for analysis.

RESULTS

1) The median maternal HMW and LMW adiponectin concentrations were lower in patients with preeclampsia than in those with normal pregnancies (P<0.001 and P=0.01, respectively); 2) patients with preeclampsia had a lower HMW/total adiponectin ratio (P<0.001) and higher MMW/total adiponectin and LMW/total adiponectin ratios than those with a normal pregnancy (P<0.001 and P=0.009, respectively); 3) the presence of preeclampsia was independently associated with lower maternal serum HMW adiponectin concentrations (P=0.001) and with a low HMW/total adiponectin ratio (P<0.001) after correction for maternal age, maternal BMI, the difference in BMI between the third and the first trimester, and gestational age at sampling; and 4) overweight/obese pregnant women had a lower median total and HMW adiponectin concentration than normal weight pregnant women among women with normal pregnancies, but not among those with preeclampsia.

CONCLUSION

1) Preeclampsia is associated with a lower median concentration of the HMW adiponectin isoform, the most active form of this adipokine, and a low HMW/total adiponectin ratio, a specific marker of adiponectin biologic activity; 2) in contrast to normal pregnancy, preeclampsia is not associated with decreased circulating adiponectin multimers in overweight/obese individuals suggesting altered regulation of this adipokine in preeclampsia; 3) collectively, these findings suggest that preeclampsia is characterized by alterations in adiponectin multimers and their relative distribution implying a role for adiponectin multimers in the mechanism of disease in preeclampsia.

A history of preeclampsia identifies women who have underlying cardiovascular risk factors

OBJECTIVE

The objective of this study was to prospectively assess physical and biochemical cardiovascular risk markers in women who had developed preeclampsia (PE) at 1 year postpartum.

STUDY DESIGN

Following an overnight fast, previously PE (n = 70) and normotensive women (n = 70) had weight and blood pressure recorded and levels of morning blood for insulin, glucose, C-reactive protein, lipids, cholesterol, and urine for microalbumin and creatinine measured. Body mass index, homeostatic model assessment index, and incidence of metabolic syndrome were determined.

RESULTS

At 1 year postpartum, markers of cardiovascular disease were different between the groups. There were also differences in the number of women with abnormal values. Mathematical modeling of cardiovascular event risk suggests that PE increases the risk by 2- to 3-fold; the risk was greatest for women with severe PE.

CONCLUSION

The development of PE is 1 of the earliest clinically identifiable markers of a woman's heightened risk of cardiovascular disease.

Haemostatic factors in women with history of preeclampsia

OBJECTIVE

Evaluation of haemostatic parameters--Plasma tissue plasminogen activator (t-PA), plasminogen activator inhibitor type 1 (PAI-1) and fibrin fragment D-dimer several years after the end of pregnancy to investigate if they are modified in women with history of preeclampsia (PE).

STUDY DESIGN

65 healthy women with history of PE and 54 control women with previous normal pregnancy were enrolled in this study. Groups were matched for age, time period since delivery, smoking status and alcohol consumption. t-PA, PAI-1 and fibrin fragment D-dimer antigen levels were quantified using standards commercial ELISA methods. Plasma fibrinogen was measured using automated capillary zone electrophoresis.

RESULTS

Systolic and diastolic blood pressures were higher in women with history of PE. Levels of t-PA, PAI-1 and fibrinogen were similar between groups as well as the t-PA/PAI-1 ratio. A significant increase in D-dimer levels was observed in women with history of PE.

CONCLUSION

The increase in D-dimer level suggests an abnormal haemostatic potential namely increased intravascular coagulation. This, together with the increased blood pressure, can reflect a tendency for an increased risk of cardiovascular/thrombotic events later in life.

Demographic, clinical and occupational characteristics associated with early onset of delivery: findings from the Duke Health and Safety Surveillance System, 2001-2004

BACKGROUND

This cross-sectional study explores associations between preterm delivery and demographic, clinical and occupational characteristics of women employed within a university and health system.

METHODS

A comprehensive surveillance system linking individual-level data from Human Resources, medical insurance claims and a job-exposure matrix was used to identify women with a single live birth between 2001 and 2004 and describe maternal characteristics during pregnancy.

RESULTS

Preterm delivery occurred in 7.1% (n = 74) of the 1,040 women, a lower preterm delivery prevalence than observed in the general U.S. population. Nearly all (>99.5%) women utilized prenatal care services. Prevalence of preterm delivery was highest for inpatient nurses, nurses' aides and office staff. In multivariate analyses, preterm delivery was positively associated with several clinical conditions: placenta previa, diabetes and cardiovascular disorder/disease.

CONCLUSIONS

We observed associations between preterm delivery and several previously indicated clinical conditions. Further study of the effect of job characteristics on preterm delivery is warranted.

Parity and cardiovascular disease risk among older women: how do pregnancy complications mediate the association?

PURPOSE

To determine whether parity is associated with increased risk of cardiovascular disease (CVD) after accounting for perinatal complications.

METHODS

CVD prevalence, number of births, and a history of preeclampsia, term low birth weight, preterm or stillbirth were evaluated among 540 women (mean age, 80 years; 47% black) enrolled in the Pittsburgh, PA site of the Health, Aging and Body Composition Study. Biomarkers were measured and CVD status was determined by self-report and hospital records.

RESULTS

Nulliparous women (n = 89) had lower CVD prevalence compared with parous women (18.0% vs. 30.2%). Parous women without perinatal complications of interest (n = 321) had higher statin use compared with nulliparas, a trend accompanied by lower high-density lipoprotein (HDL) and higher triglycerides among women with perinatal complications (n = 130). After adjustment, parous women with no complicated births had a 1.95-fold (95% confidence interval [CI], 1.03-3.7) higher CVD prevalence compared to nulliparas. Among women with one or more pregnancy complications, CVD prevalence was 2.67 times (CI, 1.34-5.33) higher. Women with five or more births had the highest CVD prevalence (odds ratio [OR], 2.60; CI, 1.17-5.76) that was attenuated to 2.27 (1.00-5.15) after adjustment for complications of interest.

CONCLUSIONS

History of pregnancy complications and higher statin use accounted for some but not all of the excess CVD prevalence among older parous women.

Activation of the fibrinolytic cascade early in pregnancy among women with spontaneous preterm birth

OBJECTIVE

To evaluate the association of early pregnancy concentrations of thrombin-antithrombin III complex with subsequent spontaneous preterm birth.

METHODS

In a nested case-control study, thrombin-antithrombin III complex was measured in plasma before 20 weeks of gestation (mean 9.9 weeks) among women without chronic conditions, preeclampsia, or growth restriction. C-reactive protein and non-high-density lipoprotein cholesterol were also measured. Women with spontaneous preterm birth before 34 weeks of gestation (n=29) and 34 weeks to 36 weeks of gestation (n=72) were compared with women with term births occurring at or after 37 weeks (n=219). Polychotomous logistic regression was used to relate elevated thrombin-antithrombin III complex (greater than 5.5 ng/mL), dyslipidemia (non-high-density lipoprotein cholesterol greater than the 90th percentile), and inflammation (C-reactive protein at or above 8 micrograms/mL) to risk of spontaneous preterm birth subtypes.

RESULTS

Women with spontaneous preterm birth compared with term births had elevated thrombin-antithrombin III complex (P=.02), and they were more likely to have a thrombin-antithrombin III complex greater than 5.5 ng/mL (P<.01). Women with thrombin-antithrombin III complex in the highest compared with lowest quartile had a 4.6-fold (95% confidence interval 1.3-15.8) increased risk for spontaneous preterm birth before 34 weeks of gestation, adjusted for body mass index, race, inflammation, dyslipidemia, and gestational age at sampling. There was a dose-response trend between thrombin-antithrombin III complex and spontaneous preterm birth before 34 weeks (P<.01) and 34 to 36 weeks (P=.03).

CONCLUSION

There is evidence of early pregnancy systemic fibrinolysis among women with spontaneous preterm birth before 34 weeks of gestation independent of inflammation and dyslipidemia, perhaps secondary to microvascular injury.

LEVEL OF EVIDENCE

II.

Cardiovascular sequelae of preeclampsia/eclampsia: a systematic review and meta-analyses

BACKGROUND

Preeclampsia affects 3% to 5% of gestations and eclampsia 0.05% to 0.93%, but their subsequent cardiovascular sequelae are unclear. The aim of this study was to determine if women with a history of preeclampsia/eclampsia are at increased risk of long-term cardiovascular sequelae.

METHODS

From Medline and Embase searches, we included case-control and cohort studies that examined cardiac, cerebrovascular or peripheral arterial disease, or cardiovascular mortality>6 weeks postpartum, in women with and without a history of preeclampsia/eclampsia and that controlled for or matched for confounders. Two independent reviewers determined study eligibility and extracted data.

RESULTS

Five case-control and 10 cohort studies met eligibility criteria, with a total of 116,175 women with and 2,259,576 women without preeclampsia/eclampsia. Most studies focused on women<56 years of age. Relative to women with uncomplicated pregnancies, women with a history of preeclampsia/eclampsia had an increased risk of subsequent cardiac disease in both the case-control studies (odds ratio 2.47, 95% CI 1.22-5.01) and the cohort studies (relative risk [RR] 2.33, 1.95-2.78), as well as an increased risk of cerebrovascular disease (RR 2.03, 1.54-2.67), peripheral arterial disease (RR 1.87, 0.94-3.73), and cardiovascular mortality (RR 2.29, 1.73-3.04). Meta-regression revealed a graded relationship between the severity of preeclampsia/eclampsia and the risk of cardiac disease (mild: RR 2.00, 1.83-2.19, moderate: RR 2.99, 2.51-3.58, severe: RR 5.36, 3.96-7.27, P<.0001).

CONCLUSIONS

Women with a history of preeclampsia/eclampsia have approximately double the risk of early cardiac, cerebrovascular, and peripheral arterial disease, and cardiovascular mortality. Further research is needed to determine the mechanisms underlying these associations and to identify effective prevention strategies.

Relaxin as a natural agent for vascular health

Hypertension, atherothrombosis, myocardial infarction, stroke, peripheral vascular disease, and renal failure are the main manifestations of cardiovascular disease (CVD), the leading cause of death and disability in developed countries. Continuing insight into the pathophysiology of CVD can allow identification of effective therapeutic strategies to reduce the occurrence of death and/or severe disabilities. In this context, a healthy endothelium is deemed crucial to proper functioning and maintenance of anatomical integrity of the vascular system in many organs. Of note, epidemiologic studies indicate that the incidence of CVD in women is very low until menopause and increases sharply thereafter. The loss of protection against CVD in post-menopausal women has been chiefly attributed to ovarian steroid deficiency. However, besides steroids, the ovary also produces the peptide hormone relaxin (RLX), which provides potent vasoactive effects which render it the most likely candidate as the elusive physiological shield against CVD in fertile women. In particular, RLX has a specific relaxant effect on peripheral and coronary vasculature, exerted by the stimulation of endogenous nitric oxide (NO) generation by cells of the vascular wall, and can induce angiogenesis. Moreover, RLX inhibits the activation of inflammatory leukocytes and platelets, which play a key role in CVD. Experimental studies performed in vascular and blood cell in vitro and in animal models of vascular dysfunction, as well as pioneer clinical observations, have provided evidence that RLX can prevent and/or improve CVD, thus offering background to clinical trials aimed at exploring the broad therapeutic potential of human recombinant RLX as a new cardiovascular drug.

Vascular dysfunction and alteration of novel and classic cardiovascular risk factors in mothers of growth restricted offspring

OBJECTIVE

Offspring and maternal birthweight are inversely associated with maternal cardiovascular disease. However, whether established or putative novel cardiovascular risk factors including vascular and metabolic function are disrupted in women who delivered small for gestational age (SGA) offspring is unknown.

METHODS

Case control study with analysis of inflammatory, lipid, metabolic and haemostatic markers and microvascular function as assessed by laser Doppler iontophoresis 4 years after the index pregnancy in 28 mothers who delivered SGA offspring at term and 29 matched controls.

RESULTS

Delivery of a SGA infant was associated with altered lipids [triglyceride median (IQR) mmol/l; control 0.64 (0.49-0.84); SGA 0.95 (0.67-0.95), p=0.012] [cholesterol:HDL ratio: control 2.64 (2.10-3.10); SGA 3.06 (2.65-3.89), p=0.013], systolic blood pressure [control mmHg: 110 (108-118); SGA 120 (110-130), p=0.031], subclinical inflammation [CRP mg/l: control 0.7 (0.3-2.1); SGA 2.2 (1.2-4.0), p=0.002] [IL-6 pg/ml: control 1.2 (0.8-1.4); SGA 1.5 (1.1-2.2), p=0.009] and endothelial activation [ICAM-1 ng/ml: control 237.7 (210.0-279.4); SGA 283.1 (240.5-366.3), p=0.013], with differences robust to confounder adjustment. Endothelium dependent (p=0.003) and independent microvascular function (p<0.001) were also impaired in mothers of SGA offspring.

CONCLUSIONS

Mothers of term SGA offspring exhibit perturbation of metabolic and vascular function, which may underlie a lifelong trajectory of impaired health incorporating adverse perinatal and cardiovascular events.

Association of elevated free fatty acids during late pregnancy with preterm delivery

OBJECTIVE

To examine the association between moderately elevated maternal plasma free fatty acids (FFAs) during late pregnancy and preterm delivery.

METHODS

In a prospective observational cohort with 523 healthy pregnant women, fasting plasma FFAs were measured during the third trimester. Socioeconomic, demographic, and anthropometric measures were collected at entry to prenatal care, and pregnancy outcomes were abstracted from medical record at delivery.

RESULTS

After control for confounders including prepregnant body mass index (multiple logistic regression analysis), women who had moderately elevated plasma FFAs (in the highest tertile), showed a greater than threefold increased risk of preterm delivery (adjusted odds ratio (AOR) 3.49, 95% (CI) 1.73-7.03, P<.001). The associations persisted in women who had spontaneous preterm delivery (AOR 2.35, 95% CI 1.05-5.28, P<.05) and after excluding women with gestational diabetes mellitus and preeclampsia (AOR 3.30, 95% CI 1.38-7.87, P<.01). Additional stratified analyses showed that the association of high maternal FFAs and increased risk of preterm delivery was independent of prepregnant obesity.

CONCLUSION

Elevated fasting plasma FFA levels at 30 weeks of gestation were associated with an increased risk of preterm delivery. This effect was independent of prepregnant obesity and several other known risk factors for preterm delivery, including cigarette smoking, ethnicity, and prior preterm delivery. These data may have important clinical significance because they provide a possible link between preterm delivery and high lipid levels, a known risk factor for cardiovascular disease.

Chronic hypertension related to risk for preterm and term small for gestational age births

OBJECTIVE

Evidence relating chronic hypertension to risk of small for gestational age (SGA) births is conflicting. To identify factors associated with SGA that may involve a placental pathogenesis, we related chronic hypertension and other maternal factors that may be markers of endothelial dysfunction to preterm compared with term SGA births.

METHODS

Chronic hypertension, diabetes, body mass index, age, and subfertility were related to risk of term and preterm SGA births in the Danish National Birth Cohort (N=81,008). Small for gestational age births were those with a birth weight adjusted for gestational age greater than two standard deviations below the mean based on fetal growth curves.

RESULTS

Risk of preterm SGA increased 5.5-fold (95% confidence interval [CI] 3.2-9.4), and risk of term SGA increased 1.5-fold (1.0-2.2) among women with definite chronic hypertension. Risk of preterm SGA but not term SGA was increased among women younger than 20 (odds ratio [OR] 2.8, 95% CI 1.1-6.8) or older than 36 (OR 2.0, 95% CI 1.3-3.1) years of age and among those with at least two early spontaneous abortions (OR 2.0, CI 1.3-3.3). Smoking, parity, time to pregnancy greater than 12 months, and underweight status were similarly related to term and preterm SGA. Overweight status, obesity, and presence of diabetes were unrelated to either SGA subtype.

CONCLUSION

Chronic hypertension, young or older maternal age, and recurrent early spontaneous abortions increased risk for preterm SGA. These factors may involve abnormal placentation and likely represent a pathogenesis distinct from that leading to term SGA.

Familial (shared environmental and genetic) factors and the foetal origins of cardiovascular diseases and type 2 diabetes: a review of the literature

Several researchers have argued that observed associations between birth weight and cardiovascular diseases, and type 2 diabetes, may be confounded by familial (shared environmental and genetic) factors. However, most studies have found that shared environmental factors, including socio-economic factors, do not influence the foetal origins of adult diseases. Results from two twin studies suggest that genetic factors may be of importance for the association between birth weight and risks of coronary heart disease, but findings from intergenerational studies are not consistent with genetic confounding. More studies have assessed the importance of genetic factors with respect to risk factors of coronary heart, including raised blood pressure and lipid levels. Recent findings suggest that the association between birth weight and hypertension is independent of genetic factors. In contrast, recent twin and intergenerational studies favour the hypothesis that the association between birth weight and risk of type 2 diabetes is confounded by genetic factors.

Preeclampsia and the risk of end-stage renal disease

BACKGROUND

It is unknown whether preeclampsia is a risk marker for subsequent end-stage renal disease (ESRD).

METHODS

We linked data from the Medical Birth Registry of Norway, which contains data on all births in Norway since 1967, with data from the Norwegian Renal Registry, which contains data on all patients receiving a diagnosis of end-stage renal disease (ESRD) since 1980, to assess the association between preeclampsia in one or more pregnancies and the subsequent development of ESRD. The study population consisted of women who had had a first singleton birth between 1967 and 1991; we included data from up to three pregnancies.

RESULTS

ESRD developed in 477 of 570,433 women a mean (+/-SD) of 17+/-9 years after the first pregnancy (overall rate, 3.7 per 100,000 women per year). Among women who had been pregnant one or more times, preeclampsia during the first pregnancy was associated with a relative risk of ESRD of 4.7 (95% confidence interval [CI], 3.6 to 6.1). Among women who had been pregnant two or more times, preeclampsia during the first pregnancy was associated with a relative risk of ESRD of 3.2 (95% CI, 2.2 to 4.9), preeclampsia during the second pregnancy with a relative risk of 6.7 (95% CI, 4.3 to 10.6), and preeclampsia during both pregnancies with a relative risk of 6.4 (95% CI, 3.0 to 13.5). Among women who had been pregnant three or more times, preeclampsia during one pregnancy was associated with a relative risk of ESRD of 6.3 (95% CI, 4.1 to 9.9), and preeclampsia during two or three pregnancies was associated with a relative risk of 15.5 (95% CI, 7.8 to 30.8). Having a low-birth-weight or preterm infant increased the relative risk of ESRD. The results were similar after adjustment for possible confounders and after exclusion of women who had kidney disease, rheumatic disease, essential hypertension, or diabetes mellitus before pregnancy.

CONCLUSIONS

Although the absolute risk of ESRD in women who have had preeclampsia is low, preeclampsia is a marker for an increased risk of subsequent ESRD.

Preeclampsia and future cardiovascular risk: formal risk factor or failed stress test?

It is estimated that 10% of pregnancies are affected by hypertension worldwide. Approximately one-half of all hypertensive pregnancy disorders are due to preeclampsia, a pregnancy-specific disorder, its distinctive feature being either sudden onset, or worsening of pre-existing proteinuria. It has become increasingly recognized that women with a history of preeclampsia are at increased risk for future cardiovascular disease (CVD), but the mechanisms of this increase in risk are unclear. One possible explanation is that these two conditions share several common metabolic abnormalities as risk factors, including obesity, insulin resistance, and lipid abnormalities that may lead to preeclampsia and CVD at different times of a woman's life. Recent studies have revealed that, similar to CVD, several mediators of endothelial cell dysfunction are up-regulated in preeclampsia. Free radical derived oxidative stress, various inflammatory markers, including neutrophil response, C-reactive protein, and leukocyte adhesion, may contribute to endothelial dysfunction in both preeclampsia and coronary atherosclerosis. Alternatively, preeclampsia itself may induce metabolic and vascular changes that may increase the overall future risk for CVD in affected women. Therefore, at present, it remains unclear whether preeclampsia is a formal risk factor for CVD, or identifies women at increased risk for CVD later in life. Pending large-scale studies aiming to examine the causality of this association, women with a history of preeclampsia should be counseled regarding their increased risks for hypertension and other cardiovascular sequelae later in life, followed closely and treated aggressively for modifiable CVD risk factors.

The relationship between racial identity, income, stress and C-reactive protein among parous women: implications for preterm birth disparity research

The persistent racial disparity in preterm birth (PTB)remains one of the most obvious yet poorly understood health disparities in the United States, and current evidence suggests that maternal stress, infection and inflammation may play an important role in the etiology of PTB. In this context, we assessed the complex relationships among racial identity; socioeconomic status (SES); psychosocial factors; and serum C-reactive protein (CRP), an inflammatory biomarker, among parous women in King County, WA. African-American women consistently reported a higher number of stressful life events than white American women (4.6 vs. 2.9, p < 0.001), as well as slightly higher levels of perceived stress and lower social support (24.7 vs. 22.2, p = 0.011, and 3.4 vs. 3.6, p = 0.06, respectively). In the multivariate analysis, African-American race, low-income status and their interaction were all independently associated with CRP; when further adjusted for proximal psychosocial, behavioral and infectious factors, race and income associations were significantly reduced. Stressful life events score was the single best proximal predictor of CRP levels (beta = 0.07 per event,p < 0.001), while perceived stress and social support were not significantly related to CRP. These results support the hypothesis that differences in CRP by racial identity and income may be mediated by differences in proximal risk factors, including stressful life events and health behaviors such as smoking. Objective life event stressors may be important to consider in future studies investigating a potential inflammatory etiology for preterm birth.

Effects of Folate and Vitamin B12 Deficiencies During Pregnancy on Fetal, Infant, and Child Development

The importance of folate in reproduction can be appreciated by considering that the existence of the vitamin was first suspected from efforts to explain a potentially fatal megaloblastic anemia in young pregnant women in India. Today, low maternal folate status during pregnancy and lactation remains a significant cause of maternal morbidity in some communities. The folate status of the neonate tends to be protected at the expense of maternal stores; nevertheless, there is mounting evidence that inadequate maternal folate status during pregnancy may lead to low infant birthweight, thereby conferring risk of developmental and long-term adverse health outcomes. Moreover, folate-related anemia during childhood and adolescence might predispose children to further infections and disease. The role of folic acid in prevention of neural tube defects (NTD) is now established, and several studies suggest that this protection may extend to some other birth defects. In terms of maternal health, clinical vitamin B12 deficiency may be a cause of infertility or recurrent spontaneous abortion. Starting pregnancy with an inadequate vitamin B12 status may increase risk of birth defects such as NTD, and may contribute to preterm delivery, although this needs further evaluation. Furthermore, inadequate vitamin B12 status in the mother may lead to frank deficiency in the infant if sufficient fetal stores of vitamin B12 are not laid down during pregnancy or are not available in breastmilk. However, the implications of starting pregnancy and lactation with low vitamin B12 status have not been sufficiently researched.

Individualized norms of optimal fetal growth: fetal growth potential

OBJECTIVE

To demonstrate that individualized optimal fetal growth norms, accounting for physiologic and pathologic determinants of fetal growth, better identify normal and abnormal outcomes of pregnancy than existing methods.

METHODS

In a prospective cohort of 38,033 singleton pregnancies, we identified 9,818 women with a completely normal outcome of pregnancy and characterized the physiologic factors affecting birth weight using multivariable regression. We used those physiologic factors to individually predict optimal growth trajectory and its variation, growth potential, for each fetus in the entire cohort. By comparing actual birth weight with growth potential, population, ultrasound, and customized norms, we calculated for each fetus achieved percentiles, by each norm. We then compared proportions of pregnancies classified as normally grown, between 10th and 90th percentile, or aberrantly grown, outside this interval, by growth potential and traditional norms, in 14,229 complicated pregnancies, 1,518 pregnancies with diabetes or hypertensive disorders, and 1,347 pregnancies with neonatal complications.

RESULTS

Nineteen physiologic factors, associated with maternal characteristics and early placental function, were identified. Growth potential norms correctly classified significantly more pregnancies than population, ultrasound, or customized norms in complicated pregnancies (26.4% compared with 18.3%, 18.7%, 22.8%, respectively, all P<.05), pregnancies with diabetes or hypertensive disorders (37.3% compared with 23.0%, 28.0%, 34.0%, respectively, all P<.05) and neonatal complications (33.3% compared with 19.7%, 24.9%, 29.8%, respectively, all P<.05).

CONCLUSION

Growth potential norms based on the physiologic determinants of birth weight are a better discriminator of aberrations of fetal growth than traditional norms.

LEVEL OF EVIDENCE

II.

Maternal educational level and risk of gestational hypertension: the Generation R Study

We examined whether maternal educational level as an indicator of socioeconomic status is associated with gestational hypertension. We also examined the extent to which the effect of education is mediated by maternal substance use (that is smoking, alcohol consumption and illegal drug use), pre-existing diabetes, anthropometrics (that is height and body mass index (BMI)) and blood pressure at enrollment. This was studied in 3262 Dutch pregnant women participating in the Generation R Study, a population-based cohort study. Level of maternal education was established by questionnaire at enrollment, and categorized into high, mid-high, mid-low and low. Diagnosis of gestational hypertension was retrieved from medical records using standard criteria. Odds ratios (OR) of gestational hypertension for educational levels were calculated, adjusted for potential confounders and additionally adjusted for potential mediators. Adjusted for age and gravidity, women with mid-low (OR: 1.52; 95% CI: 1.02, 2.27) and low education (OR: 1.30; 95% CI: 0.80, 2.12) had a higher risk of gestational hypertension than women with high education. Additional adjustment for substance use, pre-existing diabetes, anthropometrics and blood pressure at enrollment attenuated these ORs to 1.09 (95% CI: 0.70, 1.69) and 0.89 (95% CI: 0.50, 1.58), respectively. These attenuations were largely due to the effects of BMI and blood pressure at enrollment. Women with relatively low educational levels have a higher risk of gestational hypertension, which is largely due to higher BMI and blood pressure levels from early pregnancy. The higher risk of gestational hypertension in these women is probably caused by pre-existing hypertensive tendencies that manifested themselves during pregnancy.

Maternal TLR4 and NOD2 gene variants, pro-inflammatory phenotype and susceptibility to early-onset preeclampsia and HELLP syndrome

BACKGROUND

Altered maternal inflammatory responses play a role in the development of preeclampsia and the hemolysis, elevated liver enzymes and low platelets (HELLP) syndrome. We examined whether allelic variants of the innate immune receptors Toll-like receptor 4 (TLR4) and nucleotide-binding oligomerization domain 2 (NOD2), that impair the inflammatory response to endotoxin, are related to preeclampsia and HELLP syndrome.

METHODS AND FINDINGS

We determined five common mutations in TLR4 (D299G and T399I) and NOD2 (R702W, G908R and L1007fs) in 340 primiparous women with a history of early-onset preeclampsia, of whom 177 women developed HELLP syndrome and in 113 women with a history of only uneventful pregnancies as controls. In addition, we assessed plasma levels of pro-inflammatory biomarkers C-reactive protein, interleukin-6, soluble intercellular adhesion molecule-1, fibrinogen and von Willebrand factor in a subset of 214 women included at least six months after delivery. After adjustment for maternal age and chronic hypertension, attenuating allelic variants of TLR4 were more common in women with a history of early-onset preeclampsia than in controls (OR 2.9 [95% CI 1.2-6.7]). Highest frequencies for TLR4 variants were observed in women who developed HELLP syndrome (adjusted OR 4.1 [95% CI 1.7-9.8]). In addition, high levels of interleukin-6 and fibrinogen were associated with a history of early-onset preeclampsia. Combined positivity for any of the TLR4 and NOD2 allelic variants and high levels of interleukin-6 was 6.9-fold more common in women with a history of early-onset preeclampsia (95% CI 2.1-23.2) compared to controls.

CONCLUSIONS

We observed an association of common TLR4 and NOD2 gene variants, and pro-inflammatory phenotype with a history of early-onset preeclampsia and HELLP syndrome. These findings suggest involvement of the maternal innate immune system in severe hypertensive disorders of pregnancy.