Unexpected Pregnancy and Ovarian Hyperstimulation Syndrome Following Ivf Cycle with all Embryos Frozen: A Case Report

Prompt recognition of pregnancy and proper medical intervention should be given to patients with late-onset OHSS, even if no embryo was transferred in the fresh cycle. We suggest that more preventive procedures for OHSS may be necessary for patients undergoing COH and receiving no embryo transfer, such as oocyte donors and patients with polycystic ovary syndrome.