To explore the prognosis and treatment experience of fetal/neonatal ovarian cyst.

Clinical data of 35 cases of fetal/neonatal ovarian cyst (38 ovarian cysts) admitted to Guangdong Women and Children Hospital from June 2014 to December 2019 were retrospectively collected, including the cyst size before and after birth, ultrasonic features, intraoperative conditions, and pathology. According to the ultrasonic features at the first prenatal detection, the ovarian cysts were divided into two groups: simple cyst group (25 cysts) and complex cyst group (13 cysts). Two independent samples t-test and Fisher exact test were used to compare the characteristics of cysts between the two groups. The outcomes and treatment experience were summarized.

(1) The ratio of intraoperative torsion in the complex cysts group was higher than that in the simple cysts group [10/13 vs 32% (8/25), Fisher exact test, P<0.05]. (2) Twenty-five simple cysts were found on the first prenatal ultrasound scan, and 32% (8/25) of them eventually transformed into complex cysts. Among these eight cysts, the maximum diameter of five cysts was >4 cm before the transformation. (3) Postnatal ultrasound found one cyst regressed spontaneously and among the remaining 37 cysts, simple and complex type cysts were accounted for 16 and 21, respectively. Among the complex type cysts, 90% (19/21) were consistent with prenatal ultrasound. (4) Out of the 21 complicated cysts, 19 were surgically removed; the remaining two cysts (maximum diameter <3 cm) were observed conservatively and disappeared spontaneously within one year. During the operation, 81% (17/21) of the complicated cysts were found with torsion and 24% (5/21) with ovarian loss.

Simple cysts can transform into complex cysts, especially the biggest diameter >4 cm. Complex fetal/neonatal ovarian cysts indicated by ultrasonography were more prone to torsion, which required postnatal operation.

Ovarian cysts; Surgical procedures, operative; Treatment outcome; Fetus; Infant, newborn