Severe ovarian hyperstimulation syndrome requiring recurrent large-volume paracenteses until 21 weeks’ gestation: a case report

To report a case of severe ovarian hyperstimulation syndrome (OHSS) persisting into the late second trimester of a singleton pregnancy.Case report.Academic tertiary care center.A 29-year-old woman with severe OHSS after fresh embryo transfer after controlled ovarian hyperstimulation requiring intervention until 21 weeks' gestation in a singleton pregnancy.Thorough evaluation of an unusual case of severe OHSS and medical/procedural management of its sequelae in the setting of ongoing pregnancy.The clinical development of severe OHSS during pregnancy and its effect on pregnancy outcomes.Severe OHSS persisted until 21 weeks' gestation with reaccumulating ascitic fluid, which impacted pregnancy outcomes.Clinicians should be aware of the risk of severe OHSS and its possible effect on pregnancy outcomes beyond the first trimester.