C5. Preeclampsia in twin pregnancies.

AIM: To identify the independent risk factors for PE development in twin pregnancies and explore the associated perinatal outcomes.

METHODS: A retrospective cohort study of twin pregnancies was performed at St George's University Hospital, London. Maternal and neonatal data were obtained from the hospital's computerised database. The Chi-square test, Mann-Whitney U test and univariate and multiple-logistic regression analyses were performed.

RESULTS: We identified a total of 1250 twin pregnancies who were under the care of SGH from 1999 to 2015. Of these, 120 (9.6%) were complicated by pre-eclampsia according to the ISSHP diagnostic criteria. Pre-eclamptic twin pregnancies were significantly associated with the following perinatal outcomes: induction of labour, emergency caesarean delivery, blood loss at delivery, postpartum haemorrhage ≥500 ml, gestational age at delivery, neonatal unit (NNU) admission and birth weight. Maternal BMI (aOR = 1.060, 95%CI = 1.022-1.099, p = 0.002), chronic hypertension (aOR = 3.131, 95%CI= 1.443-6.792, p = 0.004), and nulliparity (aOR = 1.852, 95% CI = 1.185-2.893, p = 0.007) were independent risk factors for the development of PE in a twin gestation.

CONCLUSIONS: Nulliparity, maternal BMI and chronic hypertension are factors that increase the risk of PE in a twin gestation, such findings hold clinical significance in relation to the management of twin pregnancies in these women.