Advancing female age is one of the “greatest enemies” of fertility. This contrasts to most males who can father children for their entire lives. If one graphs female age against declining fertility, there is a direct relationship which culminates in the menopause.
Mores and values in our society have changed and many women want to establish their careers prior to having children. Data also indicate that women are waiting later in life to marry. The divorce rate is high and many women who marry again wish to start a new family.
Unfortunately, women’s biologic clocks do not synchronize with our relatively new societal clocks. If families were planned based upon the most fertile period,women would be having babies in their teens.
Although medical disorders may cause infertility in couples over 40, more often the decreased chance for pregnancy is due to the normal changes which occur in the woman’s ovaries with aging.
The hypothalamus and pituitary gland, located in the brain, orchestrate the events leading to ovulation and regular menstruation. The hypothalamus stimulates the pituitary to release follicle stimulating hormone (FSH) and luteinizing hormone (LH). These hormones are secreted into the bloodstream and control the growth of eggs (oocytes) and the production of the female hormone, estrogen, by the ovaries.
Most women have about 300,000 eggs in their ovaries at puberty. For each egg that matures and is released (ovulated) during a menstrual cycle, at least 500 to 1000 do not fully mature and are reabsorbed by the body. By the time a woman reaches menopause, which usually occurs between 40 and 56 years of age, there are only several thousand eggs remaining.
The reason we see a decline in fertility as females age is that egg quality diminishes. This is often referred to as “ovarian reserve” or the ability of the eggs to successfully fertilize and develop. One measure of ovarian reserve is the cycle day 3 level of follicle stimulating hormone. Values above 10 mcg/ml indicate diminished ovarian reserve and less likelihood of pregnancy.
An elevated blood FSH level on the third day of the menstrual cycle suggests that the ovary is not responding normally to the signals from the pituitary. This lack of ovarian responsiveness is indirect evidence of poor egg quality.
The decrease in the ovary’s response to FSH and LH from the pituitary gland results in a lowering of estrogen and progesterone produced by the ovary. The menstrual cycle may become shorter and eventually the ovaries may not release an egg, resulting in a skipped period. In addition, the hormones estrogen and progesterone are critical for the normal development of the lining of the uterus (endometrium), where the early embryo must attach in order to grow. A reduction in hormones from the ovaries with age is therefore thought to decrease the chances for pregnancy.
Fertility After 40
It is a biological fact that there is a decrease in fertility with advancing age. It is estimated that the chance of becoming pregnant in any one month is about 20 percent in women under 30, but only 5 percent in women over 40. Even with advanced infertility treatments, such as in vitro fertilization (IVF), fertility decreases and the chance of miscarriage increases in women after age 40.
The testes tend to get slightly smaller and softer with age. Sperm morphology (shape) and motility (movement) also tend to decline. Despite these changes, there is no maximum age at which men are not capable of conceiving a child, as evidenced by occasions when men in their 60s and 70s conceive with younger partners. Sexual functioning in men may also change with aging. Often there is a slight decrease in a man’s testosterone level which can cause a decrease in libido (sexual drive). Men may have difficulty achieving and/or maintaining erections as they age.
These changes in testosterone, libido, and sexual functioning may not be strictly due to aging, but can be caused by illness, stress, or reactions to medications, all of which tend to occur more frequently as men get older. Furthermore, not all men experience significant changes in sexual functioning as they age, especially men who maintain good health over the years.
In vitro fertilization (IVF) is often an option for couples with diminishing ovarian reserve. Many of these couples choose to use an egg donor depending upon the day 3 FSH level and many other factors. The Clomid Challenge Test (CCCT) is often used to predict the likelihood that a woman can achieve pregnancy using her own eggs. The CCCT protocol is as follows:
- Blood is drawn for an E2 (Estradiol) level and FSH (Follicle Stimulating Hormone level) on Day 2, 3 or 4 of the menstrual cycle.
- Clomid is administered at 100 mg per day on Day 5 of menses.
- Clomid is taken on cycle Days 5-9 and patients return to the office on cycle Day 10 or 11 (after 5 days of Clomid). The FSH level will be repeated on Day 10 or 11.
- A level from 10-12.5 mIU/mL a poor response to FSH.
- A level of 12.5-15 mIU/mL predicts a poor prognosis, but pregnancies do occur.
- Levels greater than 15 mIU/mL indicate that infertility treatment with the patient’s own eggs is not likely to succeed.
We do not deny IVF treatments to couples who fail the CCCT. We do, however, thoroughly explain that the likelihood of success using their eggs is very low.
Donated Eggs or Third Party Surrogacy Can Offer a Solution
The advantage to using donated eggs is that the success rates equal that of the egg donor’s age group, not the recipient’s. For example, if the eggs from a 23 year old woman are used in an IVF cycle where the recipient is 44, the success rates will approximate that of the 23 year old age group. In fact, as long as the recipient has no major health issues and she has a normal uterus, the upper age limit for pregnancy is not known. Women in their sixties have successfully used donor eggs to achieve pregnancy and deliver healthy children; however, most donor egg programs establish an upper age limit for the mother.
We have an active, very successful donor egg program. We use the services of Alternative Conceptions in order to provide couples with an extensive list of donors as well as third party gestationals (women who will carry the pregnancy) to choose from. Our physicians and embryologists have extensive assisted reproductive technology experience which is manifest in our superior IVF and Donor Egg IVF success rates.