Word: profet
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Dates: during 1990-1999
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...what about women who are pregnant or have gone through menopause? Since they don't menstruate, how do they ward off bacteria? Profet notes that in the first six months of pregnancy and in some cases after menopause, the cervical entryway to the uterus is covered by a mucous plug. The mucus makes it hard for sperm -- and their nasty hitchhikers -- to enter the uterus, and thus reduces the need for a monthly blood flow. Profet suspects that doctors may be making a serious mistake by routinely regarding irregular bleeding as an endocrine problem to be stopped with hormone therapy...
...back her theory, Profet relies on electron-microscopy studies that show bacteria attached to the heads and tails of wriggling sperm. She also cites the existence of spiral-shaped arteries in the uterus. These specialized blood vessels constrict and dilate in a sequence timed to induce menstruation. And, she claims, the blood that washes over the uterine walls differs from blood that circulates throughout the rest of the body. Menstrual blood lacks ingredients that cause clotting and is rich in special immune cells called macrophages. Even so, says Debrovner, "there is no reason to believe that blood, no matter what...
Another debatable point is Profet's claim that menstruation is widespread in mammals. She acknowledges that this part of her theory is speculative, but she predicts she will eventually be proved right. "You can't say these animals don't menstruate just because you can't see it," she explains. "You have to dissect them to find it." Rasweiler agrees, but so far, he insists, there is little evidence that any more than a handful of species -- including primates, bats and elephant shrews -- menstruate. "If other species don't, that raises % the question of how they rid themselves of pathogens...
Taking a page from Profet's own method, some critics challenge her by citing history. Today's women can have 400 menstrual periods over a lifetime, but earlier women probably had only a few dozen. Without birth control, they spent most of their reproductive lives pregnant or nursing. "Women were never meant to menstruate on an ongoing basis," says Dr. David Olive, the head of endocrinology at Yale University medical school. If menstruation is supposed to be a rare phenomenon, then how can it be a primary defense against infection? In fact, it may turn out that menstruation...
...debate Profet has started may not be easily resolved. If nothing else, though, she has provided a fresh way of looking at an old mystery. It's not enough, she says, to know what happens during menstruation. The more intriguing questions: Why does it happen, and how did it help humans survive to be among evolution's winners...