Human reproduction requires a perfect balance of so many factors that to scientists it seems little short of miraculous that the process ever succeeds. Yet for centuries man has failed to find an acceptable, safe, sure and economical way to thwart it. He has tried about a dozen.
ABSTENTION. The only sure method.
WITHDRAWAL before climax. Far from certain, and emotionally disturbing to both partners.
RHYTHM. Based on the fact that a woman can conceive only within about 24 hours after ovulation. This usually occurs twelve to 16 days after the beginning of each menstrual...