Recent studies have suggested that treating mild gestational diabetes in pregnant women significantly improves outcomes for both mother and child. But those studies did not identify whether the improved outcomes in children differ with the infant’s sex.
To answer this question, researchers funded by the Pregnancy and Perinatology Branch analyzed data from a large, multisite, randomized trial of treatment for mild gestational diabetes during pregnancy. They looked at 469 pregnancies with male infants and 463 pregnancies with female infants. Among the women pregnant with boys, 244 were treated for their diabetes with nutrition counseling and diet, with insulin as needed. The remaining 225 received routine prenatal care but were treated with insulin if necessary. Among women pregnant with girls, 233 received treatment and the remaining 230 were given routine care.
The researchers found significant differences in birth weight and fat mass among boys born to mothers treated for their gestational diabetes, but not among girls. This outcome suggests a differential benefit for male offspring from treatment of gestational diabetes.
The lower birth weight found in the male infants did not result from less lean body weight but rather because the infants had less body fat. This distinction is important because newborn fat mass has been linked to childhood obesity and impaired glucose tolerance, increasing risk for heart disease and possibly leading to diabetes (PMID: 22542118).