Gestational weight gain in twin pregnancies and maternal and child health: a systematic review

Abstract

Our objective was to systematically review the data interrogating the association between gestational weight gain (GWG) and maternal and child health among women with twin gestations. We identified 15 articles of twin gestations that studied GWG in relation to a maternal, perinatal, or child health outcome and controlled for gestational age at delivery and prepregnancy body mass index. A positive association between GWG and fetal size was consistently found. Evidence on preterm birth and pregnancy complications was inconsistent. The existing studies suffer from serious methodological weaknesses, including not properly accounting for the strong correlation between gestational duration and GWG and not controlling for chorionicity. In addition, serious perinatal outcomes were not studied, and no research is available on the association between GWG and outcomes beyond birth. Our systematic review underscores that GWG in twin gestations is a neglected area of research. Rigorous studies are needed to inform future evidence-based guidelines.

Early-Pregnancy Vitamin D Deficiency and Risk of Preterm Birth Subtypes

“…In a case-cohort study that included 767 cases of spontaneous preterm birth <35 weeks (15), maternal 25-hydroxyvitamin D<30 nmol/L at 20 weeks were associated with 50% increase in confounder-adjusted risk compared with 25-hydroxyvitamin D≥75 nmol/L among non-white mothers (n=556 cases), but vitamin D was not associated among white mothers (n=211 cases). In a study of twin pregnancies, the risks of preterm birth <35 and <32 significantly declined as serum 25-hydroxyvitamin D at 24–28 weeks increased (33), and like the results in our present analysis, did not vary by race and ethnicity.…”

Pregnancy Weight Gain by Gestational Age in Women with Uncomplicated Dichorionic Twin Pregnancies

“…In 1990 and again in 2009, the Institute of Medicine (IOM) recognized the importance of identifying optimal weight gain ranges for women with twin pregnancies . Yet, as highlighted in a recent systematic review, the evidence base to inform weight gain guidelines for twin pregnancies is extremely limited . The 2009 IOM Committee was only able to produce provisional weight gain guidelines for twin pregnancies, which were based on the observed interquartile range of weight gain observed in a single study of mothers who delivered twins weighing at least 2500 g at ≥36 weeks gestation…”

Weight Gain for Gestational‐Age Charts in Dichorionic Twins: Tool for Establishing Optimal Weight Gain in Twin Pregnancies

“…There is an urgent need to establish evidenced‐based recommendations for pregnancy weight gain in twin gestations for clinical research and practice. Women carrying twins experience higher rates of adverse pregnancy, obstetrical, and birth outcomes linked to low and excessive pregnancy weight gain in singletons, and the risks are even higher among those conceived with assisted reproductive techniques . But whether these outcomes are linked to pregnancy weight gain remains unclear.…”

“…Most studies of twin pregnancy weight gain and pregnancy/birth outcomes have been conducted in dichorionic twin gestations, have evaluated total weight gain rather than the pattern across pregnancy, and have had insufficient numbers to draw meaningful conclusions about women with prepregnancy underweight or severe obesity. Moreover, disentangling the effects of pregnancy weight gain from the duration of pregnancy on perinatal outcomes is challenging and sometimes prone to reverse causation, as adverse outcomes and gestational age are highly correlated and, understandably, women who deliver early have less time to gain weight …”