Preterm prelabor rupture of membranes and fetal survival after minimally invasive fetal surgery: a systematic review of the literature.

OBJECTIVE Iatrogenic preterm prelabor rupture of membranes (iPPROM; <37 weeks of gestation) is a major complication of fetal surgery. Little information is available about risk factors and incidence. METHODS We systematically reviewed reported iPPROM rates, gestational age at delivery and fetal survival after representative minimally invasive antenatal procedures. RESULTS A total of 1,146, 36 and 194 cases with mean iPPROM rates of 27, 31 and 26% were included for placental laser in twin-twin transfusion syndrome, shunting in lower urinary tract obstruction and interventions for twin-reversed arterial perfusion, respectively. In the statistical analysis, the maximum diameter of the instrument predicted iPPROM rate and was significantly related to gestational age at birth as well as fetal survival. Information on duration of the respective procedures was scarce and did not allow for meaningful analysis. CONCLUSIONS iPPROM occurs in about 30% of cases treated by minimally invasive fetal surgery. The maximum diameter of the instrument explains iPPROM rate, gestational age at birth and fetal survival. Great variations in the reporting of iPPROM make data analysis difficult.