Maternal and neonatal outcomes according to gestational weight gain in twin pregnancies: Are the Institute of Medicine guidelines associated with better outcomes?

OBJECTIVE: The Institute of Medicine (IOM) recommended a gestational weight gain for full-term twin pregnancies of 17-25 kg for normal Body mass Index patients', and characterize its guidelines on during twin pregnancies as "provisional". Indeed, they are exclusively based on observational epidemiological data. The objective of this study was to investigate whether the IOM's gestational weight gain guidelines are optimal for maternal and neonatal. OUTCOMES STUDY DESIGN: We included all consecutive twin pregnancies delivering two live births retrospectively. Monoamniotic pregnancies, major congenital abnormalities, twin-to-twin transfusion syndrome, patients with missing gestational weight gain data in the last month before delivery, and patients with a body mass index (BMI) ≤18.5 were excluded. To control for gestational length, we divided the total weight gain by the gestational age in weeks at the last weight measurement to obtain the weight gain per week. Patients were classified as having low gestational weight gain, adequate gestational weight gain, or excessive gestational weight gain, with the results adjusted for BMI and tobacco use. RESULTS: There were 878 patients in our level-III university hospital maternity ward who met the inclusion criteria in 1997-2013. Excessive gestational weight gain women had greater rates of preeclampsia than adequate gestational weight gain women did. Low gestational weight gain women showed a lower rate of gestational hypertension than AGWG women did. Delivery before 37 weeks of gestation (26.9% vs. 17.3%, p = 0.009), birth weight <2500 g, respiratory distress syndrome, and transfer to the neonatal intensive care unit were more frequent in the LGWG group compared with the AGWG group. Apgar score <7 at 5 min were more frequent in the EGWG group. CONCLUSION: Adequate gestational weight gain was associated with better outcomes. Our results suggest that the IOM guidelines for twin pregnancy are appropriate and therefore should be routinely used.