Menopause is the natural end to the reproductive phase of a woman’s life. Usually between the age of 45 to 58 years, the ovaries no longer respond to stimulation from the brain to produce ova (eggs), and menstruation stops completely.

This is frequently preceded by a period of irregular cycles called perimenopause which may be brief or may extend for many years.

Three main changes indicate that a woman is in perimenopause:

  1. variations in cycle length
  2. modification in the menstrual flow
  3. and possibly anovulatory episodes

Changes in Cycle Length

Variations in cycle lengths result from ovulation happening either earlier in the cycle than it previously occurred (creating shorter cycles), or later in the cycle (creating longer cycles).

We define two phases when we discuss cycle length in perimenopause:

During the first phase of perimenopause, menstrual cycles tend to shorten while they remain relatively regular. For example, a woman whose cycles used to vary from 28 to 30 days will vary from 25 to 28 days in her late 30s or early 40s. This phase often goes by unnoticed.

During the second phase of perimenopause, menstrual cycles gradually become more and more irregular. At first there can be one isolated cycle that is one or two weeks longer than normal, followed by many ovulatory cycles of the usual length. Later, longer ovulatory cycles will be more and more frequent, but still interspersed with occasional short cycles. Closer to menopause, cycles may last for up to several months, however occasional short cycles can still occur.

Menstrual Flow

For most women between adolescence and perimenopause the menstrual flow is heaviest for a few days, and then tapers off gradually. When women reach ages 35 to 45, it often becomes irregular. The menstrual flow may last longer or shorter, and be more or less abundant than before. But sometimes flow may vary during the same menstrual period from spotting to very abundant, or it may contain blood clots (especially following long cycles).

Anovulatory Bleeding

When an ovary fails to respond to hormonal signals, a follicle does not develop, and ovulation does not occur. During the second phase of perimenopause, this is a common occurrence. A woman will then experience anovulatory bleeding, which is the shedding of the superficial layers of the lining of the uterus (this is not true menstruation). Blood flow can range from brief or spotty to excessively heavy or long lasting.

Will the Symptothermal Method of natural family planning still be applicable and effective during perimenopause?

Yes, the Symptothermal Method, as taught by SERENA, is still applicable and effective during perimenopause.

The Symptothermal Method teaches couples to recognize the approach of ovulation and the fertile time, as well as to confirm when ovulation is passed and the definitely infertile phase is reached. Thus, irregularities in cycle length do not reduce effectiveness, unlike the Calendar Method (Rhythm), which would no longer be reliable, due to the possible irregular cycle length.

Couples can continue to effectively achieve their family planning goals by using the Symptothermal Method throughout perimenopause.