Managing Fertility in Perimenopause Years

The uncertainty of fertility in the later reproductive years can be a source of great anxiety. Although over age 35 the fertility rates decline, naturally conceived pregnancy can occur up to the mid 50’s. In the United States, between 1997 and 1999, there were 539 births to women over 50.

So, how do you know when you are in menopause and don’t have to be aware of your fertility? Well, menopause is usually defined as the cessation of menstruation for six to twelve months associated with other signs, such as hot flashes. During this time, the FSH is elevated, usually greater than 25. The period leading up to menopause is characterized by waxing and waning ovarian function. There are extended periods of anovulation when the FSH can reach the postmenopausal ranges, but then followed by occasional follicular development and ovulation (and thus a chance of pregnancy). Therefore, FSH should not be used to diagnose menopause in women with continued cycles.

Fertility control in the perimenopausal period takes careful consideration. Although pregnancy rates are lower, the health risks of unexpected pregnancy can be greater, not to mention the lifestyle changes that would be involved. While many physicians may prescribe hormonal contraception in this age group, the risk of death is higher after 40 with oral contraceptives than with pregnancy. According to the Physicians’ Desk Reference, the annual number of deaths from oral contraceptive use after the age of 40 is 31.6/100,000 women if they don’t smoke, 117.2/100,000 women if they do smoke. If the women use no fertility control method, their annual death rate related to the pregnancies is 28.2/100,000 women. In contrast, the women using periodic abstinence had a rate of 3.6/100,000 women. I believe if they had only included the women using the modern techniques of NFP, the rates would have been even lower.

So, clearly, natural family planning is one of the safest options for women over 40. However, is it effective? One study following women from 38-54 years old using the Billings Method showed a method-related pregnancy rate of zero. There was one pregnancy when a woman chose a day of fertility for intercourse. Other studies have also shown that the effectiveness of NFP is greater in the women over 40 as compared to younger age groups. In choosing a natural family planning method, I would suggest a method based on mucus observations, as the temperature will be less helpful due to frequent anovulatory cycles. It is also important to have a trained natural family planning practitioner working with you, to help you gain confidence in the system as quickly as possible.

Truly, Natural Family Planning is a great method from the start of a woman’s reproductive years, til the completion in menopause.

I wish you peace as you make your transition in life.

Sincerely,
Lynn Keenan, MD