o indicate thatthe pill may also protect its users against severalrelatively common ailments, including irondeficiency anemia (the result of heavy menstrualbleeding), pelvic inflammatory disease, and somebenign breast disorders. In addition (and contraryto fears that were expressed when the pills werefirst marketed and contained much higher levels ofhormones), long-term statistical studies point to alower incidence of ovarian and uterine canceramong women who use contraceptive pills. Otherstudies, however, have linked its use with theincreased occurrence of breast cancer. Ongoingstudies by such organizations as the AmericanCancer Society continue to study a possible breastcancer link. For some users, the pill may haveundesirable and sometimes serious side effectssuch as weight gain, nausea, hypertension, or theformation of blood clots or noncancerous livertumors. The risk of such effects increases abovethe age of 35 among women who smoke. Pills areobtainable only by prescription and after awoman's medical history and check of her physicalcondition. In 1991 the FDA approved the use ofNorplant, a long-lasting contraceptive that isimplanted under the skin on the inside of awoman's upper arm. The implant consists of sixmatchstick-size flexible tubes that contain asynthetic hormone called progestin. Releasedslowly and steadily over a five-year period, thisdrug inhibits ovulation and thickens cervicalmucus, preventing sperm from reaching eggs.Avoiding Intercourse The time to avoid sex, whenconception is not desired, is about midway in awoman's menstrual cycle; this was not discovereduntil the 1930s, when studies established that anegg is released (ovulation) from an ovary aboutonce a month, usually about 14 days before thenext menstrual flow. Conception may occur if theegg is fertilized during the next 24 hours or so or ifintercourse happens a day or two before or afterthe egg is released, because live sperm can still bepresent. Therefore, th...
