Women's Health Community

Dear southernopal: So you have been off birth control pills for the past three years, and during that time your cycles have been increasingly irregular. If you had any possible risk of pregnancy, that is the first condition to be assessed. If the pregnancy test is negative, or if you are not sexually active, then the next most common cause of a missed period is not having ovulated that cycle(s).

In a normal cycle, estrogen is produced all month. Estrogen is responsible for building up the lining of your uterus so you have something to shed each month. In a normal cycle, progesterone production increases following ovulation. Progesterone "stabilizes" the uterine lining in preparation for a possible implantation of a new pregnancy. If you are not pregnant that month the levels of estrogen and progesterone fall, triggering the release of the uterine lining—your period.

So, if you do not ovulate, the estrogen build up of the lining continues, but without the usual ovulation associated progesterone. Thus, the hormone levels don't decline, and the lining stays up inside the uterus—your missed period(s).

If you have been several months without a period, a gynecologist may give you some progesterone in a pill form (eg Provera 10 mg for 5 days). Within 48-72 hours after stopping the progesterone your "progesterone blood level" will fall, triggering the release of the lining that has been building up. Many women report that these periods are very heavy-- as though several months of lining are shed.

Causes for not ovulating are multifold: low thyroid, pituitary problems, ovarian cysts, physical stressors (eg sudden increases in exercise, crash dieting), emotional stressors (problems with parents or boyfriends/girlfriends, exams), increased body weight, anorexia, rotating shifts at work, etc.Certainly the current stress of a new job superimposed on a prior pattern of less frequent ovulations could push your periods to 6 months apart.

There is a second, less common cause for not having a period. In some women the estrogen levels become very low. The levels are so low that no uterine lining is available to be shed. When these women are given the progesterone pills to take, no flow occurs after the medication is finished. This tells the GYN that the woman is not making enough estrogen to produce a thickened uterine lining. Two causes for this to happen include premature ovarian failure (POF) or an elevated prolactin level from a pituitary gland mass.

Bottom line, you really deserve a more "for sure" answer after blood tests for low thyroid and high prolactin, and a trial of Provera or some other progesterone. Your best bet is to see a GYN or even your local county family planning clinic

Yours,
Jane