Does an irregular menstrual cycle make you less fertile?

Every woman's menstrual cycle can get thrown off by a number of factors at some point in her menstrual history. Our article answers some pointed questions about abnormal menstrual cycles and how they might affect a woman's fertility.

Why is my period irregular?

Your best friend can set her watch by the arrival of her period — the fourth Monday of every month, between 4 and 5 PM. You, on the other hand, bounce between four-, five-, and six-week cycles. You may even skip a menstrual cycle every once in a while.


What's going on here? It may reassure you to know that somewhat irregular menstrual cycles are actually more common than regular ones. Your cycle may fluctuate for a variety of reasons, including illness, travel, stress, exercise level, and significant weight loss or gain. Adolescents, women who are breastfeeding, and those who have recently stopped taking birth control pills also commonly experience fluctuations in their menstrual cycles.

Should I worry if my menstrual cycle is irregular?

Are you less likely to get pregnant than your punctual friend? Not necessarily. Fertility depends on ovulation — the release of a healthy egg from the ovary — rather than on menstruation. As long as you're ovulating normally and can determine when ovulation occurs, your chances of getting pregnant won't be affected by irregular periods.

The exception to this rule is if your cycles are very long. It's mathematically obvious that women who ovulate every six weeks — or about nine times a year — have fewer opportunities to get pregnant than those who ovulate monthly. For this reason, women with long cycles are sometimes given fertility drugs like Clomid to regulate ovulation. Women over 35 and those who don't ovulate regularly are more likely to be candidates for drug therapy than are those who simply have irregular cycles.

Tips for Maximizing Fertility

If your cycle is irregular, it's impossible to "guesstimate" when ovulation will occur. You must use ovulation predictor kits (OPKs), examine your cervical mucus, or take daily basal body temperature (BBT) readings — preferably some combination of the three.

If you exercise a great deal — say, if you work out every day for several hours, or you're in training for a marathon — speak to your doctor to determine whether you need to cut back. Women need a certain level of body fat in order to ovulate normally.

If you're seriously overweight, speak to your doctor about starting a gradual weight-loss program. Obesity may affect hormonal signals to the ovaries and interfere with ovulation. In addition, increased weight can cause insulin levels to climb, causing the ovaries to overproduce male hormones and stop releasing eggs.

Use meditation or other relaxation techniques to help keep stress levels down.


Lots More Information

Related Articles

  • Foust, Linda, The Single Parent's Almanac (Prima, 1996); American Society for Reproductive Medicine,; Weschler, Toni, Taking Charge of Your Fertility (HarperCollins, revised ed. 2001)

The information on this Web site is designed for educational purposes only. It is not intended to be a substitute for informed medical advice or care. You should not use this information to diagnose or treat any health problems or illnesses without consulting your pediatrician or family doctor. Please consult a doctor with any questions or concerns you might have regarding your or your child's condition.

Content courtesy of American Baby