Fertility And Cycle Length
A team of Swedish researchers, headed up by Dr. Thomas Brodin has discovered that the length of a woman's menstrual cycle can tell us about her level of fertility. Brodin and his team are located at Malarsjukhuset Hospital in Eskilstuna, Sweden. The researchers took a close look at 6,271 successful in vitro fertilization (IVF) procedures and were able to correlate them to the length of the patients' menstrual cycles. This study was published in Fertility and Sterility.
The research team found that as women aged, their menstrual cycles shortened bit by bit. Women were seen to lose a predictable number of days—around 2 days every year—as they passed through her 20's and on, all the way through their 40's. Once the researchers factored in the ages of the study participants, it became very clear that a woman's cycle length had a direct correlation on whether she could still conceive and have a baby. The number of women having successful deliveries following IVF cycles—those with the longest cycles (numbering more than 34 days)—was almost double that of the older women, who had cycles of fewer than 26 days.
When asked to comment on changes in the menstrual cycle, Dr. Kayode Afolabi, a consulting obstetrician and gynecologist at Oyo State's Iabadan University College Hospital (UCH), said that such changes signify that a cycle is either abnormal or that a woman has failed to ovulate. The shortened cycle is known as oligomenorrhea. When oligomenorrhea occurs, or when menstruation ceases to occur for several months and then restarts, this is a clue that ovulation is not happening with any regularity. Where there is a failure to ovulate, it becomes impossible for a pregnancy to take place.
Afolabi explains that applying the term "abnormal" to menstrual cycles only means that the period comes more or less often, changes in terms of the amount of discharge, or stops altogether. Scantier periods hint at a failure to ovulate. This happens often and is the result of changes in the levels of the hormones. For some women, prolactin levels rise, causing a reduction in menstrual flow. The ovaries respond to the rising levels of prolactin by reducing the number of eggs produced.
Other hormones may be the reason behind observed changes in the menses. If a woman begins to produce too much thyroid, for example, she will have a scantier or perhaps an altogether absent menses. But, the abnormal menstruation may be due to other reasons. There may be a blockage, or perhaps the abnormality is the after-affects of a vaginal infection. A woman who has undergone a D & C procedure may begin to experience an abnormal menstrual cycle, too.