Incidence and risk factors for Preeclampsia in a cohort of healthy nulliparous pregnant women: a nested case-control study.

The objective of this study is to determine the incidence, socio-demographic and clinical risk factors for preeclampsia and associated maternal and perinatal adverse outcomes. This is a nested case-control derived from the multicentre cohort study Preterm SAMBA, in five different centres in Brazil, with nulliparous healthy pregnant women. Clinical data were prospectively collected, and risk factors were assessed comparatively between PE cases and controls using risk ratio (RR) (95% CI) plus multivariate analysis. Complete data were available for 1,165 participants. The incidence of preeclampsia was 7.5%. Body mass index determined at the first medical visit and diastolic blood pressure over 75 mmHg at 20 weeks of gestation were independently associated with the occurrence of preeclampsia. Women with preeclampsia sustained a higher incidence of adverse maternal outcomes, including C-section (3.5 fold), preterm birth below 34 weeks of gestation (3.9 fold) and hospital stay longer than 5 days (5.8 fold) than controls. They also had worse perinatal outcomes, including lower birthweight (a mean 379 g lower), small for gestational age babies (RR 2.45 [1.52-3.95]), 5-minute Apgar score less than 7 (RR 2.11 [1.03-4.29]), NICU admission (RR 3.34 [1.61-6.9]) and Neonatal Near Miss (3.65 [1.78-7.49]). Weight gain rate per week, obesity and diastolic blood pressure equal to or higher than 75 mmHg at 20 weeks of gestation were shown to be associated with preeclampsia. Preeclampsia also led to a higher number of C-sections and prolonged hospital admission, in addition to worse neonatal outcomes

Clinical and epidemiological factors associated with spontaneous preterm birth: a multicentre cohort of low risk nulliparous women

The objective of this study was to determine incidence and risk factors associated with spontaneous preterm birth (sPTB). It was a prospective multicentre cohort study performed in five Brazilian referral maternity hospitals and enrolling nulliparous women at 19–21 weeks. Comprehensive maternal data collected during three study visits were addressed as potentially associated factors for sPTB. Bivariate and multivariate analysis estimated risk ratios. The main outcomes measures were birth before 37 weeks due to spontaneous preterm labour or premature rupture of membranes (sPTB). The comparison group was comprised of women with term births (≥37weeks). Outcome data was available for 1,165 women, 6.7% of whom had sPTB, 16% had consumed alcohol and 5% had used other illicit drugs during the first half of pregnancy. Current drinking at 19–21 weeks (RR 3.96 95% CI [1.04–15.05]) and a short cervix from 18–24 weeks (RR 4.52 95% CI [1.08–19.01]) correlated with sPTB on bivariate analysis. Increased incidence of sPTB occurred in underweight women gaining weight below quartile 1 (14.8%), obese women gaining weight above quartile 3 (14.3%), women with a short cervix (<25 mm) at 18–24 weeks (31.2%) and those with a short cervix and vaginal bleeding in the first half of pregnancy (40%). Cervical length (RRadj 4.52 95% CI [1.08–19.01]) was independently associated with sPTB. In conclusion, the incidence of sPTB increased in some maternal phenotypes, representing potential groups of interest, the focus of preventive strategies. Similarly, nulliparous women with a short cervix in the second trimester require further exploration