Spontaneous ovarian hyperstimulation syndrome (OHSS) is an extremely rare condition that occurs in pregnant women without the use of ovulation induction therapy. If not diagnosed early and treated promptly, it can lead to significant morbidity and mortality. Few cases of spontaneous OHSS have been reported in the published literature. We present the case of a 24‐year‐old pregnant woman, gravida 3 para 2, diagnosed with spontaneous OHSS secondary to previously undiagnosed primary hypothyroidism at 18 weeks of gestation. She presented with large, mobile bilateral adnexal masses and grossly enlarged ovaries containing multilobulated cysts with thin septations. Clinical, laboratory, and imaging findings confirmed the diagnosis of spontaneous OHSS. Treatment with levothyroxine resulted in complete resolution of ovarian enlargement, leading to a successful pregnancy outcome without complications related to OHSS. Her pregnancy resulted in the delivery of a 2.2‐kg healthy baby girl via uncomplicated spontaneous vaginal delivery, with return of the ovaries to normal size. This case highlights the rarity of spontaneous OHSS and explores the potential link between primary hypothyroidism and ovarian hyperstimulation, as evidenced by the shrinkage of ovarian cysts following thyroid hormone replacement therapy. This study is aimed at enhancing understanding of the underlying mechanisms behind this unusual association.
Andonie et al. (Thu,) studied this question.