Gestational weight gain in twin gestations and pregnancy outcomes: a systematic review and meta-analysis.

BACKGROUND: Data on the association of inappropriate gestational weight gain (GWG) and adverse outcomes in twin pregnancies are limited and inconsistent. OBJECTIVES: To perform a systematic review and meta-analysis on the association between GWG and adverse outcomes in twin pregnancies. SEARCH STRATEGY: Ovid, Medline, EMBASE and Cochrane Central databases from 1 January 1990 until 23 September 2020. SELECTION CRITERIA: Interventional and observational studies evaluating the association between GWG and adverse outcomes in twin pregnancies. DATA COLLECTION AND ANALYSIS: Data were extracted by two independent reviewers. Summary odds ratios (OR) were calculated using a random-effects model in a subset of studies that analysed GWG as a categorical variable in relation to the Institute of Medicine (IOM) recommendations. The primary outcome was preterm birth. MAIN RESULTS: From 277 citations, 19 studies involving 36 023 women with twin pregnancies were included in the qualitative analysis, of which 14 were included in the meta-analysis. Overall, 56.8% of women experienced inappropriate GWG: 35.4% (95% CI 30.0-41.0%) gained weight below and 21.4% (95% CI 14.2-29.5%) gained weight above IOM recommendations. Compared with GWG within IOM guidelines, GWG below IOM guidelines was associated with preterm birth before 32 weeks of gestation (OR 3.38; 95% CI 2.05-5.58), and a reduction in the risk of pre-eclampsia (OR 0.68; 95% CI 0.48-0.97). GWG above IOM guidelines was associated with an increased risk of pre-eclampsia that was consistent across all body mass index categories. CONCLUSIONS: Inappropriate GWG affects over half of twin pregnancies, so is a common and potentially modifiable risk factor for preterm birth and pre-eclampsia.

Amniotic fluid volume at presentation with early preterm prelabor rupture of membranes and association with severe neonatal respiratory morbidity.

OBJECTIVE: Amniotic fluid volume (AFV) plays an important role in early fetal lung development, and oligohydramnios in early pregnancy is associated with pulmonary hypoplasia. The aim of this study was to evaluate the association between AFV at the time of presentation with early preterm prelabor rupture of membranes (PPROM) and severe neonatal respiratory morbidity and other adverse pregnancy outcomes. METHODS: This was a retrospective study of all women with a singleton pregnancy, admitted to a single tertiary referral center between 2004 and 2014, for expectant management of PPROM at 20 + 0 to 28 + 6 weeks' gestation. The primary exposure was AFV at presentation, classified according to sonographic maximum vertical pocket (MVP) as: normal AFV (> 2 cm), oligohydramnios (≤ 2 cm and > 1 cm) or severe oligohydramnios (≤ 1 cm). The primary outcome was a composite variable of severe respiratory morbidity, defined as either of the following: (1) need for respiratory support in the form of mechanical ventilation using an endotracheal tube for ≥ 72 h and need for surfactant; or (2) bronchopulmonary dysplasia, defined as requirement for oxygen at postmenstrual age of 36 weeks or at the time of transfer to a Level-II facility. Adjusted odds ratios (aOR) and 95% CI for the primary and secondary outcomes were calculated for each AFV-at-presentation group (using normal AFV as the reference), adjusting for gestational age (GA) at PPROM, latency period, birth weight, mode of delivery and chorioamnionitis. RESULTS: In total, 580 women were included, of whom 304 (52.4%) had normal AFV, 161 (27.8%) had oligohydramnios and 115 (19.8%) had severe oligohydramnios at presentation. The rates of severe respiratory morbidity were 16.1%, 26.7% and 45.2%, respectively. Compared with normal AFV at presentation, oligohydramnios (aOR, 3.27; 95% CI, 1.84-5.84) and severe oligohydramnios (aOR, 4.11; 95% CI, 2.26-7.56) at presentation were associated independently with severe respiratory morbidity. Other variables that were associated independently with the primary outcome were GA at PPROM (aOR, 0.54; 95% CI, 0.43-0.69), latency period (aOR, 0.94; 95% CI, 0.91-0.98) and Cesarean delivery (aOR, 2.01; 95% CI, 1.21-3.32). CONCLUSIONS: In women with early PPROM, AFV at presentation, as assessed by the MVP on ultrasound examination, is associated independently with severe neonatal respiratory morbidity. This information may be taken into consideration when counseling women with early PPROM regarding neonatal outcome and management options. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.