Women born preterm or with inappropriate weight for gestational age are at risk of subsequent gestational diabetes and pre-eclampsia

Introduction

Low birthweight, which can be caused by inappropriate intrauterine growth or prematurity, is associated with development of gestational diabetes mellitus (GDM) as well as pre-eclampsia later in life, but the relative effects of prematurity and inappropriate intrauterine growth remain uncertain.

Methods

Through nation-wide registries we identified all Danish mothers in the years 1989–2007. Two separate cohorts consisting mothers born 1974–1977 (n = 84219) and 1978–1981 (n = 32376) were studied, due to different methods of registering birthweight and gestational age in the two periods. Data was linked with information on GDM, pre-eclampsia and education.

Results

In a multivariate logistic regression model the odds of developing GDM was increased by 5–7% for each week the mother was born before term (p = 0.018 for 1974–1977, p = 0.048 for 1978–1981), while the odds were increased by 13–17% for each standard deviation (SD) reduction in birthweight for gestational age for those who were small or normal for gestational age (p<0.0001 and p = 0.035) and increased by 118–122% for each SD increase above the normal range (p<0.0001 and p = 0.024). The odds of pre-eclampsia was increased by 3–5% for each week the mother was born before term (p = 0.064 and p = 0.04), while the odds were increased 11–12% for each SD reduction in birthweight for gestational age (p<0.0001 and p = 0.0002).

Conclusion

In this cohort of young Danish mothers, being born premature or with increasingly low birthweight for gestational age was associated with an increased risk of GDM and pre-eclampsia in adulthood, while increasingly high birthweight for gestational age was associated with an increased risk of GDM and a decreased risk of pre-eclampsia. Inappropriate weight for gestational age was a more important risk factor than prematurity.     

Angiogenic factors in women ten years after severe very early onset preeclampsia

Background

Women with a history of mainly severe and early onset preeclampsia have an increased risk of future cardiovascular disease. During these complicated pregnancies increased levels of anti-angiogenic factors can be found. We hypothesize that women with a history of severe very early onset preeclampsia still have increased levels of these biomarkers years after this pregnancy, resulting in increased risk for cardiovascular disease.

Methods

Twenty women with severe early onset preeclampsia before 24 weeks'' gestation, who delivered between 1993–2003 in a tertiary referral centre and twenty matched controls with uncomplicated pregnancies and healthy term infants, were addressed for participation in the study. Venous plasma samples were analyzed for basic fibroblast growth factor (bFGF), placental growth factor (PLGF), soluble fms-like tyrosine kinase-1 (sFlt-1), vascular endothelial growth factor (VEGF), E- and P-selectin, soluble intercellular adhesion molecule-3 (sICAM-3) and thrombomodulin by ELISA.

Results

Sixteen case subjects and 18 control subjects consented participation. The median time interval index pregnancy to study was 9.4 and 9.7 years for cases and controls, respectively. Median levels for cases-controls (p-value) were not different; bFGF: 17.43–11.11 pg/mL (0.33), sFlt-1: 102.98–101.92 pg/ml (0.84), PLGF: 3.57–4.20 pg/mL (0.38), VEGF: 64.05–45.72 pg/mL (0.73), E-selectin: 5.11–4.68 ng/mL (0.20), P-selectin: 85.35–71.69 ng/mL (0.69), sICAM-3: 0.42–0.63 ng/mL (0.41) and Thrombomodulin: 0.92–0.93 ng/mL (0.59).

Conclusion

There were no differences in angiogenic biomarkers between women with a history of severe early onset preeclampsia versus uncomplicated pregnancy almost 10 years later, suggesting that these angiogenic factors will not contribute to the early detection of women at risk for future cardiovascular disease.     

Soluble fms-Like tyrosine kinase 1 (sFlt1), endoglin and placental growth factor (PlGF) in preeclampsia among high risk pregnancies

Background

Differences in circulating concentrations of antiangiogenic factors sFlt1 and soluble endoglin (sEng) and the pro-angiogenic growth factor PlGF are reported to precede the onset of preeclampsia weeks to months in low-risk pregnant women. The objective of this study was to investigate whether similar changes can be detected in pregnant women at high-risk to develop the syndrome.

Methods

This study is a secondary analysis of the NICHD MFMU trial of aspirin to prevent preeclampsia in high-risk pregnancies. Serum samples were available from 194 women with pre-existing diabetes, 313 with chronic hypertension, 234 with multifetal gestation, and 252 with a history of preeclampsia in a previous pregnancy. Samples collected across pregnancy were analyzed in a blinded fashion for sFlt1, sEng and PlGF.

Results

The odds of developing preeclampsia were significantly increased among women with multiple fetuses for each 2-fold elevation in sFlt1, sEng and the ratio of angiogenic factors (e.g. OR 2.18, 95% CI 1.46-3.32), and significantly decreased for each 2-fold elevation in circulating PlGF (OR 0.50, 95% CI 0.30-0.82) between 7 and 26 weeks'' gestation. Cross-sectional analysis of the angiogenic factors across gestation showed significant differences during the third trimester in women who develop preeclampsia compared with appropriate controls in all high-risk groups. However, when data were examined in relation to the gestational week when preeclampsia was diagnosed only sFlt1 was significantly higher 2 to 5 weeks before the clinical onset of preeclampsia and only in women with previous preeclampsia.

Conclusions

The pattern of elevated concentrations of sFlt1 and sEng, and low PlGF in high-risk pregnant subjects who develop preeclampsia is similar to that reported in low-risk pregnant women. However, differences in these factors among high-risk women who do and do not develop preeclampsia are modest, and do not appear to be clinically useful predictors in these high-risk pregnant women.     

Optimal Timing of Delivery among Low-Risk Women with Prior Caesarean Section: A Secondary Analysis of the WHO Multicountry Survey on Maternal and Newborn Health

Objective

To investigate optimal timing of elective repeat caesarean section among low-risk pregnant women with prior caesarean section in a multicountry sample from largely low- and middle-income countries.

Design

Secondary analysis of a cross-sectional study.

Setting

Twenty-nine countries from the World Health Organization Multicountry Survey on Maternal and Newborn Health.

Population

29,647 women with prior caesarean section and no pregnancy complications in their current pregnancy who delivered a term singleton (live birth and stillbirth) at gestational age 37–41 weeks by pre-labour caesarean section, intra-partum caesarean section, or vaginal birth following spontaneous onset of labour.

Methods

We compared the rate of short-term adverse maternal and newborn outcomes following pre-labour caesarean section at a given gestational age, to those following ongoing pregnancies beyond that gestational age.

Main Outcome Measures

Severe maternal outcomes, neonatal morbidity, and intra-hospital early neonatal mortality.

Results

Odds of neonatal morbidity and intra-hospital early neonatal mortality were 0.48 (95% confidence interval [CI] 0.39–0.60) and 0.31 (95% CI 0.16–0.58) times lower for ongoing pregnancies compared to pre-labour caesarean section at 37 weeks. We did not find any significant change in the risk of severe maternal outcomes between pre-labour caesarean section at a given gestational age and ongoing pregnancies beyond that gestational age.

Conclusions

Elective repeat caesarean section at 37 weeks had higher risk of neonatal morbidity and mortality compared to ongoing pregnancy, however risks at later gestational ages did not differ between groups.     

Presence of antibodies against Coxiella burnetii and risk of spontaneous abortion: a nested case-control study

Background and Aims

Q fever is a bacterial zoonosis caused by infection with Coxiella burnetii. It is well established that Q fever causes fetal loss in small ruminants. The suspicion has been raised that pregnant women may also experience adverse pregnancy outcome when the infection is acquired or reactivated during pregnancy. The purpose of this study was to assess the potential association between serologic markers of infection with C.burnetii and spontaneous abortion.

Methods

A nested case-control study within the Danish National Birth Cohort, a cohort of 100,418 pregnancies recruited from 1996–2002. Women were recruited in first trimester of pregnancy and followed prospectively. Median gestational age at enrolment was 8 weeks (25 and 75 percentiles: 7 weeks; 10 weeks). During pregnancy, a blood sample was collected at gestational week 6–12 and stored in a bio bank. For this study, a case sample of 218 pregnancies was drawn randomly among the pregnancies in the cohort which ended with a miscarriage before 22 gestational weeks, and a reference group of 482 pregnancies was selected in a random fashion among all pregnancies in the cohort. From these pregnancies, serum samples were screened for antibodies against C. burnetii in a commercial enzyme-linked immunosorbent assay (ELISA). Samples that proved IgG or IgM antibody positive were subsequently confirmatory tested by an immunofluorescence (IFA) test.

Results

Among cases, 11 (5%) were C. burnetii positive in ELISA of which one was confirmed in the IFA assay compared to 29 (6%) ELISA positive and 3 IFA confirmed in the random sample.

Conclusions

We found no evidence of a higher prevalence of C.burnetii antibodies in serum samples from women who later miscarried and the present study does not indicate a major association between Q fever infection and spontaneous abortion in humans. Very early first trimester abortions were, however, not included in the study.     

Exposure to non-steroidal anti-inflammatory drugs during pregnancy and the risk of selected birth defects: a prospective cohort study

Background

Since use of non-steroidal anti-inflammatory drugs (NSAIDs) during pregnancy is common, small increases in the risk of birth defects may have significant implications for public health. Results of human studies on the teratogenic risks of NSAIDs are inconsistent. Therefore, we evaluated the risk of selected birth defects after prenatal exposure to prescribed and over-the-counter NSAIDs.

Methods and Findings

We used data on 69,929 women enrolled in the Norwegian Mother and Child Cohort Study between 1999 and 2006. Data on NSAID exposure were available from a self-administered questionnaire completed around gestational week 17. Information on pregnancy outcome was obtained from the Medical Birth Registry of Norway. Only birth defects suspected to be associated with NSAID exposure based upon proposed teratogenic mechanisms and previous studies were included in the multivariable logistic regression analyses. A total of 3,023 women used NSAIDs in gestational weeks 0–12 and 64,074 women did not report NSAID use in early pregnancy. No associations were observed between overall exposure to NSAIDs during pregnancy and the selected birth defects separately or as a group (adjusted odds ratio 0.7, 95% confidence interval 0.4–1.1). Associations between maternal use of specific types of NSAIDs and the selected birth defects were not found either, although an increased risk was seen for septal defects and exposure to multiple NSAIDs based on small numbers (2 exposed cases; crude odds ratio 3.9, 95% confidence interval 0.9–15.7).

Conclusions

Exposure to NSAIDs during the first 12 weeks of gestation does not seem to be associated with an increased risk of the selected birth defects. However, due to the small numbers of NSAID-exposed infants for the individual birth defect categories, increases in the risks of specific birth defects could not be excluded.     

Ultrasound evidence of early fetal growth restriction after maternal malaria infection

Background

Intermittent preventive treatment (IPT), the main strategy to prevent malaria and reduce anaemia and low birthweight, focuses on the second half of pregnancy. However, intrauterine growth restriction may occur earlier in pregnancy. The aim of this study was to measure the effects of malaria in the first half of pregnancy by comparing the fetal biparietal diameter (BPD) of infected and uninfected women whose pregnancies had been accurately dated by crown rump length (CRL) before 14 weeks of gestation.

Methodology/Principal Findings

In 3,779 women living on the Thai-Myanmar border who delivered a normal singleton live born baby between 2001–10 and who had gestational age estimated by CRL measurement <14 weeks, the observed and expected BPD z-scores (<24 weeks) in pregnancies that were (n = 336) and were not (n = 3,443) complicated by malaria between the two scans were compared. The mean (standard deviation) fetal BPD z-scores in women with Plasmodium (P) falciparum and/or P.vivax malaria infections were significantly lower than in non-infected pregnancies; −0.57 (1.13) versus −0.10 (1.17), p<0.001. Even a single or an asymptomatic malaria episode resulted in a significantly lower z-score. Fetal female sex (p<0.001) and low body mass index (p = 0.01) were also independently associated with a smaller BPD in multivariate analysis.

Conclusions/Significance

Despite early treatment in all positive women, one or more (a)symptomatic P.falciparum or P.vivax malaria infections in the first half of pregnancy result in a smaller than expected mid-trimester fetal head diameter. Strategies to prevent malaria in pregnancy should include early pregnancy.     

Dengue infection and miscarriage: a prospective case control study

Background

Dengue is the most prevalent mosquito borne infection worldwide. Vertical transmissions after maternal dengue infection to the fetus and pregnancy losses in relation to dengue illness have been reported. The relationship of dengue to miscarriage is not known.

Method

We aimed to establish the relationship of recent dengue infection and miscarriage. Women who presented with miscarriage (up to 22 weeks gestation) to our hospital were approached to participate in the study. For each case of miscarriage, we recruited 3 controls with viable pregnancies at a similar gestation. A brief questionnaire on recent febrile illness and prior dengue infection was answered. Blood was drawn from participants, processed and the frozen serum was stored. Stored sera were thawed and then tested in batches with dengue specific IgM capture ELISA, dengue non-structural protein 1 (NS1) antigen and dengue specific IgG ELISA tests. Controls remained in the analysis if their pregnancies continued beyond 22 weeks gestation. Tests were run on 116 case and 341 control sera. One case (a misdiagnosed viable early pregnancy) plus 45 controls (39 lost to follow up and six subsequent late miscarriages) were excluded from analysis.

Findings

Dengue specific IgM or dengue NS1 antigen (indicating recent dengue infection) was positive in 6/115 (5·2%) cases and 5/296 (1·7%) controls RR 3·1 (95% CI 1·0–10) P = 0·047. Maternal age, gestational age, parity and ethnicity were dissimilar between cases and controls. After adjustments for these factors, recent dengue infection remained significantly more frequently detected in cases than controls (AOR 4·2 95% CI 1·2–14 P = 0·023).

Interpretation

Recent dengue infections were more frequently detected in women presenting with miscarriage than in controls whose pregnancies were viable. After adjustments for confounders, the positive association remained.     

Pregnancy complications among women born preterm

Background:

Adults who were born with low birth weights are at increased risk of cardiovascular and metabolic conditions, including pregnancy complications. Low birth weight can result from intrauterine growth restriction, preterm birth or both. We examined the relation between preterm birth and pregnancy complications later in life.

Methods:

We conducted a population-based cohort study in the province of Quebec involving 7405 women born preterm (554 < 32 weeks, 6851 at 32–36 weeks) and a matched cohort of 16 714 born at term between 1976 and 1995 who had a live birth or stillbirth between 1987 and 2008. The primary outcome measures were pregnancy complications (gestational diabetes, gestational hypertension, and preeclampsia or eclampsia).

Results:

Overall, 19.9% of women born at less than 32 weeks, 13.2% born at 32–36 weeks and 11.7% born at term had at least 1 pregnancy complication at least once during the study period (p < 0.001). Women born small for gestational age (both term and preterm) had increased odds of having at least 1 pregnancy complication compared with women born at term and at appropriate weight for gestational age. After adjustment for various factors, including birth weight for gestational age, the odds of pregnancy complications associated with preterm birth was elevated by 1.95-fold (95% confidence interval [CI] 1.54–2.47) among women born before 32 weeks’ gestation and 1.14-fold (95% CI 1.03–1.25) among those born at 32–36 weeks’ gestation relative to women born at term.

Interpretation:

Being born preterm, in addition to, and independent of, being small for gestational age, was associated with a significantly increased risk of later having pregnancy complications.Numerous studies examining cohorts born mostly in the first half of the 20th century have emphasized the inverse relation between low birth weight and incidence later in life of cardiovascular and metabolic conditions, such as hypertension and type 2 diabetes.¹ Epidemiologic studies seldom consider the effects of preterm birth and intrauterine growth restriction separately when studying the relation of these factors to low birth weight. Studies have suggested that adolescents and young adults born preterm have higher incidence of risk factors for metabolic (insulin resistance) and cardiovascular (higher blood pressure) dysfunctions.^2–4 With the increased survival of preterm newborns over the past 30 years, a substantially greater proportion of young adults are born before 37 or even 32 weeks’ gestation and thus may represent a growing population at risk for conditions related to metabolic syndrome as they get older.Pregnancy can be considered a stress test for future cardiovascular and metabolic health. Women with a history of gestational diabetes, gestational hypertension or preeclampsia are at increased risk of metabolic syndrome later in life.^5–7 Furthermore, studies have shown that women born with low birth weights are at increased risk of gestational hypertension, preeclampsia and gestational diabetes.^8–10 However, many of these studies either have not taken into account gestational age or have a number of shortcomings, such as small sample, young population (mostly teenagers), degree of prematurity not specified or study population consisting mostly of late preterm births.^6,11,12In the province of Quebec, weight and gestational age have been recorded in a registry for all births since 1976, and data on all hospital-based diagnoses have been collected since 1987. The aim of our study was to examine the relation between preterm birth and later pregnancy complications, independently of intrauterine growth restriction, among women born preterm in Quebec between 1976 and 1995 who delivered at least 1 newborn between 1987 and 2008. We also examined whether this association represents a dose–response relation, namely, whether the more prematurely born a woman is, the greater her risk of gestational diabetes, gestational hypertension, preeclampsia or eclampsia.     

Gestational age patterns of fetal and neonatal mortality in Europe: results from the Euro-Peristat project

Background

The first European Perinatal Health Report showed wide variability between European countries in fetal (2.6–9.1‰) and neonatal (1.6–5.7‰) mortality rates in 2004. We investigated gestational age patterns of fetal and neonatal mortality to improve our understanding of the differences between countries with low and high mortality.

Methodology/Principal Findings

Data on 29 countries/regions participating in the Euro-Peristat project were analyzed. Most European countries had no limits for the registration of live births, but substantial variations in limits for registration of stillbirths before 28 weeks of gestation existed. Country rankings changed markedly after excluding deaths most likely to be affected by registration differences (22–23 weeks for neonatal mortality and 22–27 weeks for fetal mortality). Countries with high fetal mortality ≥28 weeks had on average higher proportions of fetal deaths at and near term (≥37 weeks), while proportions of fetal deaths at earlier gestational ages (28–31 and 32–36 weeks) were higher in low fetal mortality countries. Countries with high neonatal mortality rates ≥24 weeks, all new member states of the European Union, had high gestational age-specific neonatal mortality rates for all gestational-age subgroups; they also had high fetal mortality, as well as high early and late neonatal mortality. In contrast, other countries with similar levels of neonatal mortality had varying levels of fetal mortality, and among these countries early and late neonatal mortality were negatively correlated.

Conclusions

For valid European comparisons, all countries should register births and deaths from at least 22 weeks of gestation and should be able to distinguish late terminations of pregnancy from stillbirths. After excluding deaths most likely to be influenced by existing registration differences, important variations in both levels and patterns of fetal and neonatal mortality rates were found. These disparities raise questions for future research about the effectiveness of medical policies and care in European countries.     

High incidence of unplanned pregnancy after antiretroviral therapy initiation: findings from a prospective cohort study in South Africa

Background

Increased fertility rates in HIV-infected women receiving antiretroviral therapy (ART) have been attributed to improved immunological function; it is unknown to what extent the rise in pregnancy rates is due to unintended pregnancies.

Methods

Non-pregnant women ages 18–35 from four public-sector ART clinics in Johannesburg, South Africa, were enrolled into a prospective cohort and followed from August 2009–March 2011. Fertility intentions, contraception and pregnancy status were measured longitudinally at participants'' routine ART clinic visits.

Findings

Of the 850 women enrolled, 822 (97%) had at least one follow-up visit and contributed 745.2 person-years (PY) at-risk for incident pregnancy. Overall, 170 pregnancies were detected in 161 women (incidence rate [IR]: 21.6/100 PY [95% confidence interval (CI): 18.5–25.2]). Of the 170 pregnancies, 105 (62%) were unplanned. Unmet need for contraception was 50% higher in women initiating ART in the past year as compared to women on ART>1 year (prevalence ratio 1.5 [95% CI: 1.1–2.0]); by two years post-ART initiation, nearly one quarter of women had at least one unplanned pregnancy. Cumulative incidence of pregnancy was equally high among recent ART initiators and ART experienced participants: 23.9% [95% CI: 16.4–34.1], 15.9% [12.0–20.8], and 21.0% [16.8–26.1] for women on ART 0–1 yr, >1 yr–2 yrs, and >2 yrs respectively (log-rank, p = 0.54). Eight hormonal contraceptive failures were detected [IR: 4.4 [95% CI: 2.2–8.9], 7/8 among women using injectable methods. Overall 47% (80/170) of pregnancies were not carried to term.

Conclusions

Rates of unintended pregnancies among women on ART are high, including women recently initiating ART with lower CD4 counts and higher viral loads. A substantial burden of pregnancy loss was observed. Integration of contraceptive services and counselling into ART care is necessary to reduce maternal and child health risks related to mistimed and unwanted pregnancies. Further research into injectable contraceptive failures on ART is warranted.     

Risk factors for preterm birth in an international prospective cohort of nulliparous women

Objectives

To identify risk factors for spontaneous preterm birth (birth <37 weeks gestation) with intact membranes (SPTB-IM) and SPTB after prelabour rupture of the membranes (SPTB-PPROM) for nulliparous pregnant women.

Design

Prospective international multicentre cohort.

Participants

3234 healthy nulliparous women with a singleton pregnancy, follow up was complete in 3184 of participants (98.5%).

Results

Of the 3184 women, 156 (4.9%) had their pregnancy complicated by SPTB; 96 (3.0%) and 60 (1.9%) in the SPTB-IM and SPTB-PPROM categories, respectively. Independent risk factors for SPTB-IM were shorter cervical length, abnormal uterine Doppler flow, use of marijuana pre-pregnancy, lack of overall feeling of well being, being of Caucasian ethnicity, having a mother with diabetes and/or a history of preeclampsia, and a family history of low birth weight babies. Independent risk factors for SPTB-PPROM were shorter cervical length, short stature, participant’s not being the first born in the family, longer time to conceive, not waking up at night, hormonal fertility treatment (excluding clomiphene), mild hypertension, family history of recurrent gestational diabetes, and maternal family history of any miscarriage (risk reduction). Low BMI (<20) nearly doubled the risk for SPTB-PPROM (odds ratio 2.64; 95% CI 1.07–6.51). The area under the receiver operating characteristics curve (AUC), after internal validation, was 0.69 for SPTB-IM and 0.79 for SPTB-PPROM.

Conclusion

The ability to predict PTB in healthy nulliparous women using clinical characteristics is modest. The dissimilarity of risk factors for SPTB-IM compared with SPTB-PPROM indicates different pathophysiological pathways underlie these distinct phenotypes.

Trial Registration

ACTR.org.au ACTRN12607000551493     

Is Gestational Hypertension Protective against Perinatal Mortality in Twin Pregnancies?

Background

Pregnancy-induced or gestational hypertension is a common pregnancy complication. Paradoxically, gestational hypertension has been associated with a protective effect against perinatal mortality in twin pregnancies in analytic models (logistic regression) without accounting for survival time. Whether this effect is real remains uncertain. This study aimed to validate the impact of gestational hypertension on perinatal mortality in twin pregnancies using a survival analysis approach.

Methods

This was a retrospective cohort study of 278,821 twin pregnancies, using the U.S. 1995–2000 matched multiple birth dataset (the largest dataset available for multiple births). Cox proportional hazard models were applied to estimate the adjusted hazard ratios (aHR) of perinatal death (stillbirth and neonatal death) comparing gestational hypertensive vs. non-hypertensive pregnancies controlling for maternal characteristics and twin cluster-level dependence.

Results

Comparing births in gestational hypertensive vs. non-hypertensive twin pregnancies, perinatal mortality rates were significantly lower (1.20% vs. 3.38%), so were neonatal mortality (0.72% vs. 2.30%) and stillbirth (0.48% vs. 1.10%) rates. The aHRs (95% confidence intervals) were 0.34 (0.31–0.38) for perinatal death, 0.31 (0.27–0.34) for neonatal death, and 0.45 (0.38–0.53) for stillbirth, respectively. The protective effect of gestational hypertension against perinatal death became weaker over advancing gestational age; the aHRs in very preterm (<32 weeks), mild preterm (32–36 weeks) and term (37+ weeks) births were 0.29, 0.48 and 0.76, respectively. The largest risk reductions in neonatal mortality were observed for infections and immaturity-related conditions.

Conclusions

Gestational hypertension appears to be beneficial for fetal survival in twin pregnancies, especially in those ending more prematurely or for deaths due to infections and immaturity-related conditions. Prospective studies are required to rule out the possibility of unmeasured confounders.     

Excess risk of maternal death from sickle cell disease in Jamaica: 1998-2007

Background

Decreases in direct maternal deaths in Jamaica have been negated by growing indirect deaths. With sickle cell disease (SCD) a consistent underlying cause, we describe the epidemiology of maternal deaths in this population.

Methods

Demographic, service delivery and cause specific mortality rates were compared among women with (n = 42) and without SCD (n = 376), and between SCD women who died in 1998–2002 and 2003–7.

Results

Women with SCD had fewer viable pregnancies (p: 0.02) despite greater access to high risk antenatal care (p: 0.001), and more often died in an intensive care unit (p: 0.002). In the most recent period (2003–7) SCD women achieved more pregnancies (median 2 vs. 3; p: 0.009), made more antenatal visits (mean 3.3 vs. 7.3; p: 0.01) and were more often admitted antenatally (p:<0.0001). The maternal mortality ratio for SCD decedents was 7–11 times higher than the general population, with 41% of deaths attributable to their disorder. Cause specific mortality was higher for cardiovascular complications, gestational hypertension and haemorrhage. Respiratory failure was the leading immediate cause of death.

Conclusions

Women with SCD experience a significant excess risk of dying in pregnancy and childbirth [MMR: (SCD) 719/100,000, (non SCD) 78/100,000]. MDG5 cannot be realised without improving care for women with SCD. Tertiary services (e.g. ventilator support) are needed at regional centres to improve outcomes in this and other high risk populations. Universal SCD screening in pregnancy in populations of African and Mediterranean descent is needed as are guidelines for managing SCD pregnancies and educating families with SCD.     

Is Fetal Growth Restriction Associated with a More Severe Maternal Phenotype in the Setting of Early Onset Pre-Eclampsia? A Retrospective Study

Background

Both pre-eclampsia and fetal growth restriction are thought to result from abnormal placental implantation in early pregnancy. Consistent with this shared pathophysiology, it is not uncommon to see growth restriction further confound the course of pre-eclampsia and vice versa. It has been previously suggested that superimposed growth restriction is associated with a more severe pre-eclamptic phenotype, however this has not been a consistent finding. Therefore, we set out to determine whether the presence of fetal growth restriction among women with severe early-onset pre-eclampsia was associated with more severe maternal disease compared to those without a growth-restricted fetus.

Methods and Findings

We undertook a retrospective cohort study of women presenting to a tertiary hospital with severe early-onset pre-eclampsia (<34 weeks'' gestation) between 2005–2009. We collected clinical data, including severity of pre-eclampsia, maternal and neonatal outcomes. Of 176 cases of severe pre-eclampsia, 39% (n = 68) were further complicated by fetal growth restriction. However, no significant difference was seen in relation to the severity of pre-eclampsia between those with or without a growth-restricted baby. The presence of concomitant growth restriction was however associated with a significantly increased risk of stillbirth (p = 0.003) and total perinatal mortality (p = 0.02).

Conclusions

The presence of fetal growth restriction among women with severe early-onset pre-eclampsia is not associated with increased severity of maternal disease. However the incidence of stillbirth and perinatal death is significantly increased in this sub-population.     

Trends in the Distribution of Gestational Age and Contribution of Planned Births in New South Wales,Australia

Background

There is concern that the rate of planned births (by pre-labour caesarean section or induction of labour) is increasing and that the gestation at which they are being conducted is decreasing. The aim of this study was to describe trends in the distribution of gestational age, and assess the contribution of planned birth to any such changes.

Methods

We utilised the New South Wales (NSW) Perinatal Data Collection to undertake a population-based study of all births in NSW, Australia 1994–2009. Trends in gestational age were determined by year, labour onset and plurality of birth.

Results

From 1994–2009, there was a gradual and steady left-shift in overall distribution of gestational age at birth, with a decline in the modal gestational age from 40 to 39 weeks. For singletons, there was a steady but significant reduction in the proportion of spontaneous births. Labour inductions increased in the proportion performed, with a gradual and changing shift in the distribution from a majority at 40 weeks to an increase at both 37–39 weeks and 41 weeks gestation. The proportion of pre-labour caesareans also increased steadily at each gestational age and doubled since 1994, with most performed at 39 weeks in 2009 compared with 38 weeks up to 2001.

Conclusions

Findings suggest a changing pattern towards births at earlier gestations, fewer births commencing spontaneously and increasing planned births. Factors associated with changing clinical practice and long-term implications on the health and well-being of mothers and babies should be assessed.     

Differences in gene expression between first and third trimester human placenta: a microarray study

Background

The human placenta is a rapidly developing organ that undergoes structural and functional changes throughout the pregnancy. Our objectives were to investigate the differences in global gene expression profile, the expression of imprinted genes and the effect of smoking in first and third trimester normal human placentas.

Materials and Methods

Placental samples were collected from 21 women with uncomplicated pregnancies delivered at term and 16 healthy women undergoing termination of pregnancy at 9–12 weeks gestation. Placental gene expression profile was evaluated by Human Genome Survey Microarray v.2.0 (Applied Biosystems) and real-time polymerase chain reaction.

Results

Almost 25% of the genes spotted on the array (n = 7519) were differentially expressed between first and third trimester placentas. Genes regulating biological processes involved in cell proliferation, cell differentiation and angiogenesis were up-regulated in the first trimester; whereas cell surface receptor mediated signal transduction, G-protein mediated signalling, ion transport, neuronal activities and chemosensory perception were up-regulated in the third trimester. Pathway analysis showed that brain and placenta might share common developmental routes. Principal component analysis based on the expression of 17 imprinted genes showed a clear separation of first and third trimester placentas, indicating that epigenetic modifications occur throughout pregnancy. In smokers, a set of genes encoding oxidoreductases were differentially expressed in both trimesters.

Conclusions

Differences in global gene expression profile between first and third trimester human placenta reflect temporal changes in placental structure and function. Epigenetic rearrangements in the human placenta seem to occur across gestation, indicating the importance of environmental influence in the developing feto-placental unit.     

Spontaneous abortion and preterm labor and delivery in nonhuman primates: evidence from a captive colony of chimpanzees (Pan troglodytes)

Background

Preterm birth is a leading cause of perinatal mortality, yet the evolutionary history of this obstetrical syndrome is largely unknown in nonhuman primate species.

Methodology/Principal Findings

We examined the length of gestation during pregnancies that occurred in a captive chimpanzee colony by inspecting veterinary and behavioral records spanning a total of thirty years. Upon examination of these records we were able to confidently estimate gestation length for 93 of the 97 (96%) pregnancies recorded at the colony. In total, 78 singleton gestations resulted in live birth, and from these pregnancies we estimated the mean gestation length of normal chimpanzee pregnancies to be 228 days, a finding consistent with other published reports. We also calculated that the range of gestation in normal chimpanzee pregnancies is approximately forty days. Of the remaining fifteen pregnancies, only one of the offspring survived, suggesting viability for chimpanzees requires a gestation of approximately 200 days. These fifteen pregnancies constitute spontaneous abortions and preterm deliveries, for which the upper gestational age limit was defined as 2 SD from the mean length of gestation (208 days).

Conclusions/Significance

The present study documents that preterm birth occurred within our study population of captive chimpanzees. As in humans, pregnancy loss is not uncommon in chimpanzees, In addition, our findings indicate that both humans and chimpanzees show a similar range of normal variation in gestation length, suggesting this was the case at the time of their last common ancestor (LCA). Nevertheless, our data suggest that whereas chimpanzees'' normal gestation length is ∼20–30 days after reaching viability, humans'' normal gestation length is approximately 50 days beyond the estimated date of viability without medical intervention. Future research using a comparative evolutionary framework should help to clarify the extent to which mechanisms at work in normal and preterm parturition are shared in these species.