Pattern of pregnancy weight gain in homozygous sickle cell disease and effect on birth size

To assess pregnancy weight gain and newborn anthropometry in mothers with homozygous sickle cell (SS) disease and normal controls.

An eleven-year retrospective review at the University Hospital of the West Indies, Kingston, Jamaica, revealed 128 singleton deliveries in women with SS disease who were matched by maternal age and birth date with 128 controls with a normal AA phenotype. Restriction to those commencing antenatal care before 16 weeks gestation resulted in the final study group of 80 SS patients and 115 AA controls. Weight and height were measured at first antenatal visit and weight at 20, 25, 30, 35 and 38 weeks gestation. Longitudinal regression used mothers'weight as the outcome, genotype as a predictor and gestational age as a random effect. Regression analyses of maternal weight on childhood anthropometry were repeated in separate maternal genotypes. Neonatal indices included gestational age, birthweight, head circumference and crown-heel length.

Mothers with SS disease had lower weight and body mass index at first antenatal clinic visit (p < 0.001). Total weight gain was 6.9 kg for SS women and 10.4 kg for AA controls (p < 0.001) and weekly weight gain 0.263 kg (95% CI 0.224, 0.301) and 0.396 kg (95% CI 0.364, 0.427) respectively. A significant relationship occurred between birthweight and maternal weight gain at 25-30 weeks gestation in AA controls but this relationship appears delayed in SS disease.

Different patterns of maternal weight gain in SS mothers and normal controls may have significance for the lower birthweight in SS mothers.