Perinatal outcomes of severe, isolated intrauterine growth restriction before 25 weeks' gestation: A retrospective cohort study.

OBJECTIVE:To evaluate the perinatal outcome associated with severe and isolated intrauterine growth restriction (IUGR) diagnosed before 25 weeks and to describe factors related to fetal death. METHODS:This retrospective study included singleton pregnancies with an estimated fetal weight (EFW) ≤ 3rd centile between 21 + 0 and 24 + 6 weeks' gestation referred between 2013 and 2020. All fetuses with morphological or chromosomal abnormalities were excluded. We constituted three groups based on perinatal outcomes to highlight poor prognostic factors: live birth, fetal death and termination of pregnancies (TOP). RESULTS:We included 98 pregnancies with an overall survival rate of 61.2% (60/98). There were 63.2% (62/98) live births, 24.5% (24/98) TOP, and 12.2% (12/98) fetal death. Of the live births, 27.4% (17/62) of fetuses were born before 32 weeks, and two died in the neonatal period (2/62; 3.2%). The fetal death rate was higher with the presence of an EFW below the first percentile (83.3% of fetal death Vs 33.8% of live births; p = 0.002), Doppler abnormalities (83.3% of fetal death Vs 6.4% of live births; p<0.001), and oligoamnios (41.9% of fetal death Vs 11.3% of live births; p = 0.05). CONCLUSION:Severe growth restriction detected before 25 weeks was associated with poor perinatal outcomes. There were more often EFW <1st percentile, abnormal Doppler and oligoamnios in cases of fetal death compared to live births.