Among the millions of words that have been written about oral contraceptives, none have been more alarming than charges that the pill causes a wide variety of illnesses, some of them serious, and a few of them fatal. Solid statistics have been lacking, but now reliable data are being assembled about two possible major dangers:
∙THROMBOPHLEBITIS. Women on 20-day pills that combine a progestin (a synthetic that acts like a pregnancy hormone) with a minute quantity of estrogen react as though they were "a little bit pregnant." Changes in the blood resemble those of pregnancy—including, for some women, an increased...