Abstract
Fetal adnexal cysts present unique challenges during pregnancy, requiring careful management strategies to mitigate risks throughout gestation and delivery. We present the case of a 35-year-old G4P2 patient, referred to our center for a large adnexal cyst confirmed by ultrasound (US) and fetal MRI, with a calculated volume of 210 mL. Given the cyst's size and the family's strong preference for vaginal delivery (VD), US-guided aspiration was performed at 35 (6/7) weeks, followed by an uncomplicated spontaneous VD at 37 (2/7) weeks. Two weeks postpartum, the ovarian cyst re-accumulated, requiring laparoscopic-assisted cystectomy in a torsed but viable left ovary. This case demonstrates the importance of individualized prenatal care, where clinical decisions balance parental preferences with medical risks. Maximizing the opportunity for vaginal birth was a top priority for the family, and the successful reduction of the cyst's size through percutaneous aspiration minimized the risk of abdominal dystocia and allowed for a safe VD. We review relevant literature, emphasizing the need for further research to refine fetal intervention criteria and improve outcomes for such cases.