Outcomes
The primary outcome of interest was a compositive measure of preterm
birth or low birthweight. Preterm birth was defined as <37
weeks, 0 days gestation. Low birthweight was defined as
<2500g. Gestational age at delivery and birthweight were
abstracted from patient-held obstetric records recorded by midwives.
Gestational age was based on the estimated date of delivery that was
calculated at the first antenatal care visit using the reported last
menstrual period and confirmed by ultrasound when available. If the last
menstrual period date was unknown or likely incorrect, symphysis-fundal
height measurements were utilized by midwives to determine gestational
age. Our study performed ultrasounds on a small sample of 20 women and
compared our findings with the recorded gestational age data using a
Mann-Whitney test and Fisher’s exact test. We found that the estimates
were not significantly different.