Many doctors disagree on when exactly pregnancy begins, according to a new survey published in the American Journal of Obstetrics and Gynecology.
"People say that the medical profession has settled on this," Dr. Farr Curlin, the senior author of the study, told Reuters. "And what our data show rather clearly is that it is not at all settled among the medical profession."
Though most of the doctors polled (57 out of every 100) believe pregnancy begins when the sperm fertilizes the egg, a minority (28 out of every 100) contend it doesn't begin until the fertilized egg implants in the uterus a week later, Reuters reports.
The American College of Obstetrics and Gynecology and federal laws define pregnancy as the implantation of the fertilized egg in the uterus, according to Reuters.
Curlin told Reuters he was surprised that most of the doctors in his study disagree with ACOG.
"In this case, the science shows exactly what happens, but what you define as pregnancy is not what science can settle," Curlin told Reuters Health.
This discrepancy can seriously impact federal law, as fertilized eggs are frequently used in stem cell research and some contraceptives prevent implantation of an egg, Reuters reports.
So if it's ever decided that pregnancy starts at fertilization, "then you see why any technology that prevents implantation would be problematic," Curlin told Reuters Health.
