Do sun protective fabrics really work?
Yes, though most studies have looked at their ability to prevent sunburn, rather than skin cancers, which can take years to develop.
Even regular clothing can keep some ultraviolet (UV) light from reaching the skin. A normal, white cotton T-shirt, for instance, provides the equivalent of a sun protection factor (SPF) of 7, though this drops to 3 when it gets wet, said Dr. Susan Weinkle, an assistant clinical professor of dermatology at the University of South Florida in Tampa. A dark, long-sleeved denim shirt, which among other things, is more tightly woven, offers great protection -- an SPF of 1,700 -- though obviously such garments are also hotter.
The ability of clothing to protect against the sun's rays depends on fabric construction, fiber content and weave, fabric color, finishing processes and the presence of additives that absorb UV light, said Weinkle, a spokesperson for the American Academy of Dermatology.
Sun protective clothing can be pricey -- $50 for a shirt -- and is sold by companies with names such as Sun Precautions of Seattle and Coolibar of Minneapolis. You can boost the UV protectiveness of regular clothing with photoprotective laundry additives such as Rit Sun Guard, which carries a "seal of recommendation" from the Skin Cancer Foundation, a private, nonprofit group in New York.
So, what do the experts say? "If you are extremely sensitive to the sun, sun protective clothing makes sense," said Dr. Bernard Cohen, interim chairman of dermatology at Johns Hopkins University School of Medicine.
And from Dr. Terry Hadley, a dermatologist at Mount Auburn Hospital in Cambridge, Mass.: "I think they're a great addition."
Is there any way for a woman to tell that her fertility is declining before it's too late?
Many women assume that as long as they're still getting their periods, they have plenty of healthy eggs left. But this is not quite true.
There may be some eggs, but they tend to be of such poor quality that they stop dividing soon after fertilization or implantation in the uterus.
Although menopause -- the permanent cessation of periods -- happens on average at age 51.5, fertility begins to decline around age 35. By 38, this decline accelerates and by 40, "it nosedives," said Dr. David Keefe, medical director of reproductive medicine at Tufts-New England Medical Center.
In addition to age, other predictors of declining fertility include: a family history of menopause before 35, smoking, surgery to remove an ovary or a cyst on an ovary, and having had chemotherapy or radiation for cancer, said Dr. Howard Zacur, director of the division of reproductive medicine and infertility at Johns Hopkins Hospital.
There is a blood test for a hormone called FSH (which stands for follicle stimulating hormone) which can to some degree predict a woman's fertility. FSH, made in the pituitary gland, tells eggs in the ovaries to mature. As a woman ages and her ovaries begin to run out of eggs, FSH levels rise.
Fertility clinics use FSH tests (usually done on day 2, 3 or 4 of a woman's cycle) to tell if she is likely to get pregnant with in vitro fertilization. In general, if the FSH level is over 10 International Units per milliliter, a woman is unlikely to get pregnant.
Although FSH levels can fluctuate from month to month, in general, "you are only as fertile as your worst FSH score," said Keefe. It's like a gas gauge on a car, he said. Once the needle registers empty, even if that's only when you're turning a corner, you are close to having an empty tank.
In the future, better tests may be available that directly measure a hormone secreted by a developing egg. Until then, Keefe recommends reading a book called What Every Woman Should Know About Fertility and Her Biological Clock, by Cara Birrittieri.
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