Menopause is defined as the day 12 consecutive months after your last menstrual period. But the period of time when estrogen and progesterone production declines and menstrual periods become irregular, called perimenopause, can begin by age 45 and, for some women, even a decade earlier. Fertility declines rapidly at this point and by age 44, only 1.9 percent of woman become pregnant using their own eggs, even with invitro-fertilization, according to the National Summary of Assisted Reproductive Technology's 2008 Survey.
Time Line of Fertility
A woman's fertility begins around the time of menarche, or her first menstrual period, and peaks in her mid 20s. From then on it steadily declines. Around age 38, changes in the uterine lining or endometrium, and a decreased level of progesterone, the hormone that maintains the pregnancy, lower the chance that her embryo will implant in the uterus even if conception occurs. By age 44, even when in-vitro fertilization is used to conceive the embryo outside her body, there is only a 1.9 percent chance that the embryo will implant successfully and result in a live birth. If a woman has already tried a precious cycle of in-vitro fertilization that failed, her chance of success using her own eggs decreases to 0,7 percent. These extremely low rates of success are important considerations because the IVF process uses financial resources and time that a woman over 44 may want to invest in options with a higher chance of success.
When a woman is trying to have a baby after 40, infertility management protocols call for a rapid assessment of her ability to conceive and implant an embryo.To accomplish this, the level of follicle stimulating hormone in her blood is assessed on day three of a menstrual cycle. If this level is over 11.4 m IU/ml, conceiving using her own eggs is statistically impossible, according to researchers at the Univerity of Pennsylvania who reported in the January 2002 issue of Human Reproduction.
Menstrual Cycle Length
A simpler and cost-free way to assess the possibility of becoming pregnant after 40 is to record your own menstrual cycle length, according to a review by Swedish researcher Thomas Brodin, M.Sci., published in the November 2008 edition of "Fertility and Sterility."
A menstrual cycle starts with the first day of menstrual bleeding and ends the day before the next menstrual period begins. Menstrual cycles average 28 days throughout most of a woman's reproductive life. Around age 44, they shorten and stay between 23 and 26 days until they lengthen out and are skipped occasionally right before the menopausal transition year. Dr. Brodin's team studied more than 6,000 in-vitro fertilization attempts and found that when a woman's menstrual cycle was 26 days long or less, her chances of success using in-vitro fertilization were reduced by 50 percent, in comparison to women of the same age who had longer cycles. Dr. Brodin found that cycle length was more important than age in determining whether a woman's own eggs were viable and whether her uterus could sustain pregnancy. This assessment is especially important for women who may be short cycling and therefore approaching menopause in their late 30s or early 40s.
Using Donor Eggs
For women who can no longer use their own eggs, there is the option of using an egg donor. Occasionally, a younger friend or relative volunteers to donate eggs, but most donations are anonymous and the couple compensates the donor financially. After medical and psychological screening, the donor's ovaries are hyperstimulated with medication and her cycle and the recipient's are synchronized using hormone manipulation. A 5- to 8-day-old embryo is then implanted. The Centers for Disease Control and Prevention reported a 55.1 percent live birth rate for IVF with donor eggs in 2007. Costs vary widely, but include the standard IVF fees and donor compensation, which can be $10,000 or more per cycle.
Surrogates and Gestational Carriers
For the older mother with diabetes, obesity, high blood pressure or other physical concerns, having another woman carry her child to term is a legal option in the United States and there are two ways to accomplish this process. In the first, a surrogate is simply impregnated artificially using sperm from the intended father. There is no need for her to take medication to hyperstimulate her ovaries and pregnancy success rates are the same as if she conceived spontaneously. Some couples, however, prefer to use an egg donor and IVF and then implant the embryo in the body of another woman, a gestational carrier who has no biological relationship to the baby. One reason to do this is that it allows for Preimplantation Genetic Diagnosis, a process of removing a cell from the 5- to 8-day-old embryo and testing it for any genetic abnormalities. PGD eliminates the need for amniocentesis and the prospect of a later termination of pregnancy or a child with a known, but incurable birth anomaly.