P04.07: Ovarian hyperstimulation syndrome (OHSS) with normal pregnancy

A 37-year-old primigravida conceived naturally, presented with abdominal pain and distension, dyspnoea and hyperemesis. All laboratory tests were normal. 12 weeks scan demonstrated no fetal heart beat, molar placenta, multicystic ovaries and ascites; consistent with a partial molar pregnancy. She underwent urgent uterine evacuation and had worsening dyspnoea and abdominal distension. CT chest abdomen pelvis revealed right pleural effusion, bilateral multicystic ovaries and large ascites. 2.7 litres peritoneal fluid was drained with no malignant cells on cytology. She responded well to supportive measures. Histopathology of product of conception demonstrated oedematous appearance of chorionic villi, normal trophoblast proliferation and no evidence of molar changes. Recent identification of FSH receptor gene mutations which increased FSH receptors sensitivity to structurally similar HCG is responsible for spontaneous OHSS. It induces follicular growth, activates LH receptors on granulosa cells and causes the release of vasoactive molecules. Clinical presentation, biochemical tests and ultrasound findings strongly supported the diagnosis of molar pregnancy but it was a non-molar miscarriage. This case would create awareness of this unusual presentation of spontaneous OHSS mimicking a partial molar pregnancy as it could cause major emotional impact on the patient and financial impact on the healthcare system. Supporting information can be found in the online version of this abstract. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.