FERTILITY FACTORS
The Ovulation Factor
Problems with ovulation are common causes of infertility, accounting for approximately 25% of all infertility cases. Ovulation involves the release of a mature egg from one of your ovaries. After ovulation, the ovary produces the hormone progesterone. During the 12 to 16 days before menstruation begins, progesterone prepares the lining of your uterus into an optimal environment for implantation and nurturing of the fertilized egg. If you have regular menstrual cycles, you are probably ovulating. Cycle lengths of approximately 24 to 34 days (from the beginning of one period to the beginning of the next period) are usually ovulatory. If you only have a period every few months or not at all, you are probably not ovulating or are ovulating infrequently.
Though it is cumbersome and not routinely recommended, charting your basal body temperature (BBT) is a simple, inexpensive way to see if you are ovulating. To complete a BBT chart (Figure 2), you must take your temperature by mouth each morning the moment you awaken while still in bed for at least one month and record the temperature under the appropriate date. Normally, the release of progesterone due to ovulation causes a mid-cycle temperature rise of 0.5 to 1.0 degrees Fahrenheit, indicating that ovulation has occurred.