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    Are Periods Obsolete?

    Women's Health Proponents Recommend Continuous Birth Control Pills


    Estrogen and progestin are the main hormones in birth control pills. Estrogen causes the uterine lining to grow and thicken; progestin inhibits ovulation and changes the secretions in the vagina that makes sperm less likely to enter to uterus. When women stop taking active pills, the uterine lining begins to shed, resulting in bleeding -- a period. Oral contraceptives were originally developed to include a monthly menstrual periods so that they would seem more "natural," but there is no real reason for it, Westhoff explains.

    While not getting monthly periods may seem unnatural, experts say that throughout the centuries, most women did not menstruate as regularly as we do today. In the past, women had an average of six pregnancies and breastfed for one to two years after each pregnancy. Today women average two or three pregnancies and breastfeed for a few months, if at all. In addition, puberty began at age 16 in the past and now the average age is just over 12. Many women in the past had their first birth at age 19, but today it is closer to 25. Menopause, too, occurs later.

    Fewer periods are healthy, says Ann Davis, MD, an assistant professor of obstetrics and gynecology at Harvard University School of Medicine in Boston.

    "It is not not-ovulating that is dangerous, but why you are not ovulating," Davis says. "If you are not using hormonal contraceptives to alter your menstrual cycle and you are not getting your periods regularly, that is unhealthy," she says. Underlying diseases including eating disorders could be too blame, she adds.

    Misperceptions about menstruation abound, says Hester M. Sonder, MD, clinical instructor of medicine at Temple University in Philadelphia. Hippocrates, the father of medicine, believed that menstruation was designed to purge women of their bad moods; ancient Roman physicians believed that contact with menstrual blood could turn wine to vinegar; and some myths persist in the 21st century.

    But, she tells WebMD, the purpose of ovulatory, "natural" menstrual cycle is to establish a pregnancy. Menstruation follows an unsuccessful cycle. "When pregnancy doesn't occur, menstruation does," she says.

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