Bodnar LM, Himes KP, Abrams B, et al. - Researchers examined how gestational weight gain in twin pregnancies is associated with small-for-gestational-age (SGA) and large-for-gestational-age (LGA) birth, preterm birth before 32 weeks of gestation, cesarean delivery, and infant death within each prepregnancy body mass index (BMI) category. For this population-based study, data of 54,836 twins born alive before 39 weeks of gestation were derived from Pennsylvania-linked infant birth and death records (2003–2013). They identified a negative correlation of gestational weight gain z score with SGA and its positive correlation with LGA and cesarean delivery in all BMI groups. In nonobese women, U-shaped relation was observed between weight gain and preterm birth. They noted adverse outcomes in correlation with very low or very high weight gains. Improvement in pregnancy outcomes might be achieved via targeted modification of pregnancy weight gain in women carrying twins, in case, the identified associations are even partially reflective of causality.