If you are a teenager just starting to menstruate, or in your 40s headed toward menopause, don’t worry if you go several months without a period. In adolescents the feedback system that regulates periods is not yet finely tuned. Women approaching menopause have irregular cycles because their ovaries no longer produce enough progesterone to maintain the regular rhythm of the system.
A girl aged 16 or 17 who has established her periods and then developed anorexia nervosa or otherwise lost a great deal of weight may stop having periods. And of course any woman who has been sexually active and ceased menstruating should consider pregnancy as a possibility.
The other day Rose Ann called, worried and upset because her period was five days late. I knew she was involved in a new relationship, so I asked whether she could be pregnant. Not a chance, she said, because she and her boyfriend had not had sex. They were waiting.
She mentioned that she had been suffering from something called irritable bowel syndrome, and that she had had severe diarrhea and had lost ten pounds in less than two months. I guessed that the weight loss had caused her to stop menstruating, and indeed after she got the diarrhea under control, her periods came back.
Changes in diet that bring about significant weight gain can also cause your periods to cease temporarily, as can drastic changes in exercise pattern. If you have been a couch potato and suddenly start running ten miles a day, you may very well stop menstruating for a time.
Tension can interfere with your menstrual cycle in a major way. If you are under heavy stress at school or have recently gone away to college, you may have irregular periods — or no periods for awhile. An illness in the family or a death can have the same effect.
Organic causes are possible too, some of them related to the endocrine system and some fairly common. The pituitary gland, which plays a major role in ovulation, produces a hormone called prolactin that acts to start milk production when you give birth. For some reason, the pituitary gland can start producing too much prolactin when you are not pregnant, and elevated levels can interfere with regular periods. Certain medications can raise your prolactin levels, notably Risperdal (risperidone), an antipsychotic drug. Women with thyroid disorders can also lose their periods. It is easy to test for thyroid function and easy to alleviate problems via medication.
Another rather rare cause is premature menopause, which can happen as early as age 35. If you are having hot flashes, sleep problems, and night sweats while you are in your early 30s, your doctor may have you tested for premature menopause. The problem is unlikely if you are in your mid-20s.
Should you be concerned about your general health if your periods stop?
If amenorrhea caused by too little estrogen continues for some time, it can affect your bones. Because you are not ovulating, and thus not producing the estrogen that protects your bones, you are at increased risk for osteoporosis (a disease in which the mineral content of bone is gradually lost). Very thin women (models, runners, ballet dancers, and women with anorexia) have this kind of risk.
Women with a lot of body fat make plenty of estrogen, even if they have no periods, so their bones are not at risk. However, because they are not getting a monthly clean-out bleed, they may develop overgrowth of the uterine lining.
Should you worry if your cycles are longer than thirty-four days?
If you are a teenager who has just started menstruating or an older woman headed for menopause, you may well have widely spaced periods. Chances are that either you are not ovulating frequently or that your hormonal levels at the time of ovulation are not quite high enough.
For women in their 20s and 30s, skipping periods or having very long cycles can cause two problems. If the underlying problem is that you don’t ovulate frequently, you may have trouble getting pregnant, but rest assured that there are ways to bring about more frequent ovulation. Very long cycles, with periods that come so far apart that they are not regular at all, can also lead to hyperplasia (overgrowth of the uterine lining). If your body fails to clean out the endometrium every 90 days or so, the uterine lining keeps growing and growing. Hyperplasia can lead to cancer if it is not treated. (See the discussion of how endometrial cancers.)
What can you do if you have very long or very short cycles?
To shorten very long cycles, your doctor may prescribe progesterone for five to twelve days every couple of months. When you stop taking the progesterone, you will have a period and thereby clean out the lining of the uterus.
If you have short cycles, say twenty-one or twenty-two days, you have no reason to worry, even though bleeding that often is rather inconvenient. If you bleed both heavily and frequently, there is some risk that you may become anemic. A red blood count will tell you whether this is a problem.
If you are unable to tolerate bleeding every three weeks, you can space your periods further apart by taking birth control pills, which shut down ovulation and then bring on a period by means of progesterone withdrawal.