© 2022 Japan Society of Obstetrics and Gynecology.Purpose: This study aimed to describe the maternal and fetal outcomes associated with expectant management following previable preterm premature rupture of membranes (PPROM) before 24 weeks of gestation. We also analyzed the risk estimates of potential confounders to clarify whether these variables are contributed to the risk of postnatal mortality among these neonates. Methods: This retrospective cohort study included all pregnant patients who experienced previable PPROM before 24 weeks of gestation at a tertiary maternal-fetal medicine center. We used the neonatal data from birth until discharge. Results: A total of 128 women were enrolled. The survival to discharge rate was 60.9%. The median latency period (80 vs. 20 days, respectively, p < 0.001) was significantly longer, the median gestational week at delivery (34 vs. 25 weeks, respectively, p < 0.001) and median birth weight (2100 vs. 710 g, p < 0.001) was significantly higher in the survivor group than the non-survivor group. Surviving neonates had significantly lower frequencies of anhydramnios at any time during the latency period than the non-survivor neonates (38.4% vs. 86.0%, respectively, p < 0.001). Conclusion: This study demonstrated an opposite correlation between the duration of latency period and gestational age at PPROM with earlier membrane rupture in pregnancies having a longer latency period, which additionally clarifies the higher gestational age at delivery. The antepartum factors that increased the possibility of postnatal mortality within our study included the gestational week at delivery, duration of the latency period, anhydramnios at any time during the latency period, and birth weight.