85 Comparison of maternal characteristics and perinatal outcomes of early and late onset preeclampsia in a tertiary care hospital of Pakistan

Abstract

Introduction Preeclampsia has two clinical entities: Early onset preeclampsia (EOP) and late onset preeclampsia (LOP). The two clinical entities could be distinct with respect to maternal characteristics and perinatal outcomes. Objectives To compare the maternal characteristics of women delivered as EOP and LOP and their perinatal outcomes. Methods We retrospectively analyzed 456 cases of preeclampsia in singleton pregnancies delivered at Aga Khan University Hospital, Karachi, Pakistan (1990–2016). Preeclampsia was defined as blood pressure of ⩾ 140/90 mmHg (taken twice, 6 h apart) combined with 2+ on dipstick protein analysis in the absence of urinary tract infection. Subjects were classified as EOP if the disease manifested before 34 weeks of gestation and LOP when manifestation was at ⩾ 34 weeks of gestation. Maternal characteristics and perinatal outcomes were compared between the two groups using students t test, Mann Whitney U test and Pearson χ 2 test, where appropriate. Results Mothers with EOP were found to be older as compared to mothers with LOP and this association was weakly significant (p value = 0.049). Significantly greater proportions of mothers with EOP had past history of preeclampsia as compared to those with LOP (p value 0.004). Proportions of primigravida were four times less common amongst EOP than LOP. However, the difference was not statistically significant (p value 0.41). There was no significant difference noted in body mass index between the two groups [EOP mean = 29.87 (SD 5.70 ± 5.24) LOP mean = 28.84 (SD 10 ± 5.71)]. EOP were four folds less likely to have cardio-metabolic disorders such as obesity and diabetes mellitus compared to LOP [Obesity 50% vs 12%; p value 0.10; Diabetes mellitus 12.8% vs 3.3%; p value 0.84). These results however, remained non-significant. The mean gestational age at delivery for EOP was significantly more remote from term as compared to LOP (31 vs 37 weeks; p value 0.001). Mothers with EOP were 1.6 times likely to be delivered by emergency section as compared to LOP (85% vs 52%; p value 0.001). Neonates born to EOP mothers demonstrated significantly less Apgar score ( 7) (p-value 0.001), were twice more likely to be admitted to neonatal intensive care unit (NICU), and to be born with intra-uterine growth restriction (IUGR) as compared to LOP (p value 0.001). EOP group were 3 times more likely to deliver low birth weight (LBW) neonates (mean birth weight = 1.33 vs 2.72 p value 0.001) and 9 times more likely to have stillbirth (1.2% vs 0.2%; p value 0.001) in comparison to LOP group. Conclusion Within the preeclamptic cohorts, mothers with EOP were older and were more likely to deliver preterm babies through emergency caesarean section. Neonates born to EOP experienced more adverse outcomes in terms of poor Apgar score 7, stillbirth, admission to NICU, LBW and IUGR as compared to those born to LOP.