The influence of sex on fetal rabbit lung maturation and on the response to glucocorticoid.

Female premature rabbit fetuses had more stable lungs than male premature rabbit fetuses. In both male and female rabbit fetuses, deflation stability increased to a similar extent after administration of glucocorticoid, but the resultant male lungs were significantly less stable. The lungs of female fetuses treated with steroid had greater histologic maturity than those of male fetuses, with a higher proportion of air space and thinner airspace after completion of pressure-volume studies. These results indicate that sex differences must be considered in studies of lung maturation.