Schirmer DA, Kulkarni AD, Zhang Y, et al. - Researchers investigated trends, predictors, and perinatal outcomes of ovarian hyperstimulation syndrome (OHSS) linked with in vitro fertilization (IVF) cycles in the United States via performing a retrospective cohort study utilizing National Assisted Reproductive Technology Surveillance System (NASS) data. Increase in the proportion of IVF cycles complicated by OHSS was noted from 10.0 to 14.3 cases per 1,000 from 2000 to 2006, and a decrease to 5.3 per 1,000 was observed from 2006 to 2015. Cycles with more than 30 oocytes retrieved were noted to be at the highest risk of OHSS. Following were the modifiable predictive factors for OHSS: number of oocytes retrieved, pregnancy following fresh embryo transfer, and the type of medication used for pituitary suppression during controlled ovarian hyperstimulation. Risk of preterm delivery and low birth weight was observed to be higher among patients affected by OHSS. Findings emphasize undertaking measures to decrease the risk of OHSS whenever possible.