To the Editor:—
"Busulfan Treatment of Leukemia During Pregnancy" is of special interest both to obstetricians and hematologists. However, the authors' conclusions concerning a lack of fetal toxicity should be accepted with some reservations.As was pointed out in my article, "Busulfan in Early Pregnancy" (Obstet Gynec27:738, 1966), many of these children are of low birth weight. In the cases documented to this time, at least 50% of the children weighed less than 2,500 gm although of term gestation. This is suggestive of an effect on fetal metabolism in utero although the role of the leukemic process itself cannot be resolved.The possible gonadal effect is an important consideration in light of animal studies.1 As the authors point out, these children have not attained puberty. It is also true, however, that there has been no good follow-up on these children.