If you’re dealing with the heartbreak of infertility, you aren’t alone. Approximately one in 10 American women has trouble getting pregnant or carrying a pregnancy to term. For women, the most common cause of infertility is a problem with ovulation. Many factors can affect a woman’s ovulation and her fertility. Here’s a look at some common ones. 1. Age In her 20’s, a woman’s chance of pregnancy is about 90%. By age 45, it declines to 15%. With age, it becomes more difficult to release an egg from an ovary. There are also fewer eggs left to release and they tend to be less healthy. Older women may also have other health problems that affect fertility. What’s more, the risk of miscarriage increases with a woman’s age. If you are under 35 and have tried for a year without success, talk with your doctor. Women 35 years or older should only wait six months before seeking help. 2. Alcohol Use Alcohol use—even as few as five drinks per week—may affect a woman’s fertility. Alcohol can disrupt normal menstrual cycling and interfere with reproductive function. A 2009 Harvard University study looked at alcohol use in couples undergoing IVF (in vitro fertilization). Women who consumed moderate amounts of alcohol—six drinks per week—decreased their chance of having a baby by 18%. If you’re trying to conceive, consider skipping alcohol all together. 3. Emotional Health Physical and emotional stress can affect reproduction. In women, stress can cause amenorrhea—or absent periods. It also affects the hormones that control ovulation. This can lead to problems releasing an egg during a normal menstrual cycle. Mental health problems, such as depression, can have a similar effect. Talk with your doctor about stress management and your mental health. 4. Environmental Factors Various environmental or occupational risks may affect a woman’s fertility. These risks include prolonged exposure to high temperatures, chemicals, radiation, and heavy electromagnetic or microwave emissions. These exposures may disrupt the menstrual cycle, damage eggs, and increase the risk of miscarriage. If you work in any of these conditions and are trying to conceive, talk with your doctor about your risk. And be sure to follow all safety procedures at work. 5. Sexually Transmitted Diseases Chlamydia and gonorrhea increase the risk of fertility problems. Left untreated, these STDs can permanently damage the fallopian tubes, uterus, and other tissues. And the infection can sometimes be “silent,” meaning you may not realize you have it. Women who are at risk include those that have multiple sex partners and don’t use condoms. Have an annual screening if you are at risk. 6. Smoking Cigarette smoking accounts for approximately 13% of infertility cases. Smoking tends to accelerate the normal decline in reproductive function. It also increases the chances of having a miscarriage. If you smoke and are considering fertility treatments, be aware that smokers may require twice as many IVF attempts compared to nonsmokers in order to conceive. 7. Weight With fertility, being either very overweight or very underweight can cause problems. About 12% of infertility cases involve weight issues. Women with body fat levels 10 to 15% above normal tend to have too much estrogen. This disrupts the normal reproductive cycle. On the other hand, women who don’t have enough body fat—10 to 15% below normal—can completely shut down their reproductive systems. Elite athletes and women who exercise intensely are at risk. Strict vegetarians, women with poor diets, and those with eating disorders may also have problems.