Women's Health Archive

Although vitamin D is essential to bone health, a controlled clinical trial published online by JAMA Internal Medicine on Aug. 3, 2015, found that vitamin D supplements didn't build bone in postmenopausal women with blood levels of vitamin D below the 30-ng/mL threshold generally considered necessary for good health. Researchers at the University of Wisconsin randomly assigned 230 women to three groups: one got 800 IU of vitamin D daily and a placebo twice a month; one got a placebo daily and 50,000 IU of vitamin D twice a month; the third got placebos both daily and twice a month. The study lasted a year. The researchers found that neither dose of vitamin D had a significant effect on bone mass, falls, or fractures.

The Wisconsin study may not have used the right doses of vitamin D or lasted long enough to show an effect. One ongoing study, The Vitamin D and Omega-3 Trial (VITAL), is large enough to demonstrate even small-to-moderate benefits of vitamin D supplementation. VITAL is evaluating a 2,000-IU daily dose for five years in 26,000 women and men. The results are expected in 2017. Until then, it's still important to get the recommended daily dose of vitamin D: 600 IU for adults through age 70 and 800 IU for people ages 71 or older

Ask the doctor

Q. I'm 62 years old, and my last menstrual period was at age 51. My doctor told me that my hot flashes would end after "about three to five years," but I still have them. Am I unusual, and what can I do?

Among 400 postmenopausal women who were previously inactive, those who did 300 minutes per week of moderate or high intensity exercise had more success at reducing total fat after one year than those who exercised for 150 minutes per week.

Urinary tract infections (UTIs) occur in women of all ages. Physical and hormonal changes can leave women at midlife particularly vulnerable. No woman should have to put up with the inconvenience and discomfort of recurrent UTIs. Self-help measures can be effective, but if they don’t do the trick, see your doctor. He or she can identify and treat any underlying problems and recommend other strategies to keep UTIs at bay.

One of the most common treatments for unexplained infertility is ovulation induction, in which a woman takes drugs that will increase the number of eggs the ovary releases in the hope that at least one will result in a pregnancy. But when too many eggs are available for fertilization, the rates of high-risk multiple pregnancies go up. A recent study compared three drugs used for ovulation induction and found that the one more likely to result in a live birth was also more likely to result in a multiple pregnancy (twins, triplets, or more). The options for treating unexplained infertility remain less than ideal, but careful choices mean that the pregnancies that do result will be safer for moms and babies.

The PREDIMED study showed that the Mediterranean diet can statistically lower a person’s risk for cardiovascular disease, including heart attacks, strokes, and death from heart-related causes. The data also suggest that a Mediterranean diet is associated with a reduced chance of getting breast cancer. This small analysis has some limitations, but provides another reason to consider this already healthful way of eating.

Ideally, screening mammography detects small breast cancers so that they can be removed before they grow, metastasize, and kill. To tell whether screening is succeeding, researchers from Harvard and Dartmouth looked at the rates of mammography, the diagnosis of small breast cancers, large breast cancers, and breast cancer deaths in 16 million women 40 or older in the United States from 2000 through 2010. They found that when mammography rates increased 10%, the number of small cancers detected went up 25%, and the number of large cancers increased by 7%. There was no decline in breast cancer deaths. They concluded that mammography is finding—and women are being treated for—small cancers that may not progress to invasive disease or metastasize to other parts of the body.

The results, which were published online July 6, 2015, by JAMA Internal Medicine, echo those of earlier findings. They underscore a dilemma facing women and their doctors: To get annual mammograms and risk being treated for a tumor that may never become harmful, or have mammograms less frequently and risk missing a cancer until it is larger. The U.S. Preventive Services Task force recommends having a mammogram every one to two years for women ages 50 to 79. The American Cancer Society suggests annual mammograms beginning at age 40. You may want to discuss your personal risk profile, and your preferences, with your doctor.

An analysis from the Women's Health Initiative (WHI) suggests not only that postmenopausal women who are overweight or obese have a higher risk of invasive breast cancer than women of normal weight but also that the excess risk increases as a woman's weight rises beyond obesity. The results were published online June 11, 2015, by JAMA Oncology.

A team of investigators from several medical centers studied data on 67,000 postmenopausal women who enrolled in the WHI between 1993 and 1998. They were followed for a median of 13 years. During that time, 3,388 invasive breast cancers were detected. The researchers analyzed the distribution of breast cancer among weight classes and calculated the risks for women who were overweight (body mass index, or BMI, of 25 to 30), obese (BMI 30 to 35), or very obese (BMI over 35) compared with women of normal weight (BMI 25 or less). They found that the increased risk of developing breast cancer ranged from 17% in women who were overweight to 59% in those with a BMI over 35. Among women who began the study at a normal weight, those who gained at least 5% of their original weight had a 12% higher risk of developing breast cancer than those who maintained their original weight. Neither losing weight nor using hormone therapy had a significant effect on risk for women of any weight.