Participants
Pregnant women were eligible to participate if they were 18 years or
older and between 24 and 28 weeks of gestation calculated using date of
last menstrual period and/or earliest obstetric ultrasound scan where
available. Women were excluded if they had one or more of the following
exclusion criteria: known diagnosis of diabetes, significant medical
comorbidity (such as heart failure, renal disease, severe anaemia),
multiple pregnancy, inability to provide informed consent, or plans to
deliver at a non-study facility.
Women were approached in the antenatal clinic by the research team and
screened for inclusion and exclusion criteria.
At recruitment, standardised questionnaires were used to
collect data on socio-demographic and lifestyle factors (including age,
level of education, smoking status and alcohol use). Questionnaires also
covered family, medical (including HIV status) and reproductive history
(parity, gravidity and complications in prior pregnancies). Weight,
height, and mid-upper-arm circumference were measured using calibrated
Seca scales, stadiometers, and flexible tape measures. After 30 minutes
of rest, three seated blood pressure measurements, with 5 minutes rest
in between, were collected on the right arm using portable
sphygmomanometers (OMRON-Healthcare-Co HEM-7211-E-Model-M6; Kyoto,
Japan). We used the mean of the last two blood pressure readings.