Pre-eclampsia: maternal risk factors and perinatal outcome

Objective: The aim of this study was to throw light on the incidence of pre-eclampsia (PE) in women attending for care and delivery at a hospital in Saudi Arabia, and analyze the maternal risk factors and outcome of mothers and neonates in pregnancies complicated by PE.

Methods: This retrospective study involved almost all women (n = 27,787) who delivered at King Fahad Hospital of the University in a 10-year period (1992-2001). The maternal records were reviewed for age, parity, gestational age, mode of delivery, antenatal care, onset of PE, severity of proteinuria, and the frequency of antenatal and intrapartum complications. The neonatal records were reviewed for perinatal outcome including birth weight, frequency of stillbirths, and neonatal deaths.

Results: Among the study cohort of pregnancies, 685 women, i.e. 2.47%, were diagnosed as having PE among whom a high proportion (42.0%) were nulliparous women. Similarly, PE was encountered at a high percentage (40.0%) in women at the extreme of their reproductive age (< 20 and >40 years), and more women with PE delivered prematurely (30.2%) as compared to healthy controls (13.5%). Spontaneous vaginal deliveries were less frequent in women with PE (69.2%) as compared with healthy controls (86.2%). Instrumental deliveries, with spontaneous labor, amounted to 15.9% in women with PE, but they comprised only 2.9% in healthy women. The deliveries were more likely to be induced (22.8%) or be performed by cesarean section (14.9%) in women with PE than in healthy controls (6.8% and 9.6%). Placental abruption was the most common maternal complication (12.6%) in women with PE, followed by oligouria (7.9%), coagulopathy (6.0%), and renal failure (4.1%). The perinatal outcome of pregnancies with PE shows that stillbirths (2.34%) and early neonatal deaths (1.02%) comprised an overall mortality rate of 33.6 per 1,000. More stillbirths and neonatal deaths showed a tendency to be associated with the severe form of PE (diastolic BP > or =120), as compared with the mild form (diastolic BP 90-110). Stillbirths and neonatal deaths appear to be associated with women who had no or irregular antenatal care and whose proteinuria amounted to or exceeded 3 g per 24 h, when delivery occurred at 28th gestational week or less, and when the birth-weight of the neonates was between 500 and 1,000 g.

Conclusion: We document a hospital-based incidence rate of PE of 2.47%, with a high proportion of PE cases occurring among nulliparous women and those at the extreme ends of the reproductive age. More maternal and neonatal complications were encountered in women with PE when the PE was severe, when the pregnancy had to be terminated early, when there was no regular antenatal care, the birth-weight was low, or the proteinuria was severe.