A technique involving a swimming race of sorts is being used at Chicago's Michael Reese Hospital and Medical Center in an effort to ensure that embryos will be male at the time of conception.
W. Paul Dmowski, MD, PhD, and co-workers are using a modified version of a technique introduced in 1973 by Ronald Ericsson, PhD, of Sausalito, Calif. So far, 14 of about 45 women have become pregnant after insemination with their husbands' semen that was collected and processed in the Fertility Unit that Dmowski directs.
Seven women gave birth to boys, four had girls, one is expecting her baby in June, and two miscarried (one of these fetuses was male; the sex of the other could not be determined at that early stage). In two of the four pregnancies that resulted in female infants, Dmowski says, coitus without contraceptive protection occurred between the time of artificial insemination and