• Mayo Clinic Q and A: Irregular periods, infertility not necessarily linked

a middle-age couple hugging and smiling at one anotherDEAR MAYO CLINIC: I'm 34, and my husband and I have been trying to get pregnant for more than a year with no luck. My periods have always been irregular. Sometimes I go three or four months without one. That’s been nerve-wracking as we try to figure out if we’re pregnant, but could it also be part of the problem? Is it time for us to see an infertility doctor?

ANSWER: Your irregular periods could be part of the reason you haven’t gotten pregnant, but that’s not necessarily the case. However, at the very least, it means you may have had fewer times when you could get pregnant. That makes it harder to time intercourse. For women in your situation, investigating a possible connection between irregular periods and infertility is a reasonable place to start. It would be a good idea for you and your husband to consult with a health care provider with expertise in evaluating infertility.

A couple is considered to have fertility issues if they have been trying to get pregnant for at least a year without success — or for at least six months if the woman is 35 or older. Infertility is common in the U.S. About 10 to 15 percent of people of reproductive age have problems with fertility.

Age can be a factor in infertility for both men and women. With women, it comes a bit earlier. Women tend to start experiencing fertility problems in their mid-30s to early 40s. For men, it tends to happen later in life, typically in the 40s and 50s. When the causes of infertility are broken down, about 40 percent come from men and about 40 percent come from women. In about 20 percent of cases, the problem involves a combination of factors that include both.

Difficulty with ovulation — which could be the source of irregular periods — accounts for infertility in about 25 percent of infertile couples. In some cases, hormonal disorders that affect the release of eggs from the ovaries are the underlying problem.

For example, polycystic ovary syndrome is a common condition in which the release of eggs from the small collections of fluid in which they grow, called follicles, is disrupted. Hyperprolactinemia, a condition in which the body makes too much of the hormone prolactin, also can interfere with ovulation. Too much thyroid hormone (hyperthyroidism) or too little (hypothyroidism) can affect the menstrual cycle or cause infertility, as well.

A less common disorder is primary ovarian insufficiency, or POI. It involves the loss of normal ovarian function before age 40. Women who have primary ovarian insufficiency might have irregular or occasional periods for years. Other causes of irregular periods that could affect fertility include excessive exercise, eating disorders, injury or tumors.

Just because you have irregular periods, however, doesn’t necessarily mean you have one of these conditions, nor is the unpredictability of your menstrual cycles automatically the cause of your infertility. Although assessing the possible causes of irregular periods is typically a starting point for investigating infertility, there are various underlying conditions that could hamper your effort to get pregnant.

A thorough evaluation of you and your partner with a health care provider who has knowledge of infertility can help define what's going on and help you decide how to best move forward. Testing usually can identify the problem within several months, or sometimes an underlying cause of infertility cannot be found. The good news is that effective therapies are often available. Studies show that about 70 percent of couples who have dealt with fertility issues go on to conceive after receiving infertility treatment. — Dr. Elizabeth Stewart, Reproductive Endocrinology and Infertility, Mayo Clinic, Rochester, Minnesota