Effect of preeclampsia on the incidence rate of small-for-gestational-age of the fetuses among pregnant women in selected public hospitals in Tigray, Northern Ethiopia

Abstract

Background: In low- and middle-income countries, including Ethiopia, small-for-gestational-age of the fetuses is a risk factor for fetal and neonatal mortality and morbidity that is linked to immediate perinatal adverse events and also to adult pathologic conditions in later life. In Ethiopia, particularly in Tigray, there is a paucity of information on the incidence rate and predictors of small-for-gestational-age of the fetuses among pregnant women.

Objective: To determine the incidence rate and predictors of small-for-gestational-age of fetuses among pregnant women in selected public hospitals in Tigray, Ethiopia.

Methods: A retrospective cohort study was conducted among preeclampsia (n = 239) and normotensive (n = 476) women who were in antenatal care follow-up before 20 weeks in selected hospitals of Tigray, from January 01, 2014, to March 31, 2019, to measure weight for gestational age of the fetuses every two to four weeks. Systematic sampling was used to select preeclampsia and normotensive women from the list in antenatal care logbook by their medical record numbers, using every three and every 25 intervals, respectively. A pre-tested structured checklist was used to extract data, then entered and cleaned using Epi Data version 3.1 and exported to Stata version 14 for analysis. The incidence rate was calculated by dividing all small-for-gestational-age of the fetus cases by the person weeks of follow-up. The Cox proportional hazard model was performed to identify predictors of small for gestational age of the fetuses.

Results: The incidence rate of small-for-gestational-age of the fetuses was higher among women with preeclampsia than normotensive women (94.5 versus 24.9 per 1,000 person weeks, Z = 9.42, p < 0.000001). A higher risk of small-for-gestational-age of the fetuses was observed among women with preeclampsia/eclampsia (AHR = 3.92, 95% CI 2.55-6.01), women with a history of low birth weight (AHR = 0.41, 95% CI 0.17-0.94), and women with poor gestational weight gain (AHR = 1.89, 95% CI 1.15-3.1).

Conclusions and recommendations: There were significant differences in the incidence rates of small-for-gestational-age of fetuses among preeclampsia, and normotensive women. Preeclampsia, a history of low birth weight and poor weight gain were significant predictors for small-for-gestational-age of the fetuses. It is necessary to strengthen the screening of preeclampsia for optimal fetal growth and to provide counseling on nutrients for adequate gestational weight gain. Further studies would also be beneficial to confirm the predictors at the community level. [Ethiop. J. Health Dev. 2020; 34(3):181-190]

Keywords: Small-for-gestational-age, preeclampsia/eclampsia, Tigray