Strengths and limitations
The study was conducted in one single tertiary hospital with smaller
sample size. We did not record the pregnancy outcomes like preterm
deliveries and the subtypes of PE among those who developed PE. So, the
values observed here may not be comparable with the one observed in
primary and secondary level settings. Also, the dropout is high in each
trimester because most of the pregnant women got registered during the
first trimester later moved out of the city to their mother’s home for
delivery. Despite the limitations, this is the first longitudinal study
of its kind in Indian settings with regular follow-up of once in each
trimester till delivery to measure the incidence of PE in the high-risk
population. Selection bias was minimized by using the nested
case-control study design compared to the traditional case-control
study.