Wen L, et al. - Researchers determined the relationship between second-trimester gestational weight gain and perinatal outcomes in twin pregnancies of the Longitudinal Twin Study (LoTiS) cohort in Chongqing, China. Outcomes revealed a higher risk of preterm birth and spontaneous preterm birth in correlation with insufficient gestational weight gain. Further, a higher risk of small for gestational age was observed in correlation with reduced gestational weight gain during 12–20 gestational weeks. Additionally, an increase in the mean birth weight of a twin pair by 45.78 g or 13.03 g was noted when gestational weight gain during 12–20 weeks or total gestational weight gain increased by 1 kg. These findings establish a correlation between maternal weight gain in the early second trimester and birth weight in dichorionic twins.