Fetal ovarian cysts: development and neonatal outcome.

Abstract

The aim of the study was to evaluate the outcome of fetal ovarian cysts in relation to their size and ultrasonic appearance. We retrospectively analysed pre- and postnatal charts of 61 infants with a prenatal diagnosis of ovarian cysts between 1991 and 2000. In a total of 61 fetuses 65 ovarian cysts were detected by transabdominal ultrasound: 35 (57 %) cysts on the left side, 22 (36 %) on the right side and 4 fetuses (7 %) had bilateral cysts. Three patients with uncomplicated cysts were lost to follow-up and one fetus with bilateral cysts died in the 27th week of gestation. In 17 cysts treatment was necessary. 14 cysts (all complicated) were operated after delivery because of persistence or enlargement. The histological results were either follicular or theca lutein cysts in 12 cases, one lymphangioma and one teratoma. Two cysts were aspirated in utero and one after delivery. In the remaining 40 fetuses, 43 cysts where only controlled by ultrasound. 8 cysts regressed before delivery and 35 cysts after delivery independent of their sonographic appearance. The mean diameter of cysts that required treatment was significantly different from the mean diameter of cysts that resolved spontaneously (6.8 [SD 2.4] cm vs. 3.3 [SD 0.8] cm; p < 0.01). Complicated cysts which do not regress should be treated either by laparotomy or laparoscopically after delivery. Uncomplicated cysts which exceed 5 cm could be treated by in utero aspiration or aspiration after delivery to avoid further complications. Cysts smaller than 5 cm, presenting the tendency to regress, should be left untouched independent of their sonographic appearance.