By Elizabeth Stein, CNM, MSN, MPH
Midwife & Leading Women’s Health Expert
Most women want a baby, later if not sooner. Once you catch baby lust, nothing will satisfy baby lust except a baby. But only 7,349 (0.6%) of over 4 million babies born (4,317,119) in 2007 were to women 45 and older – that’s only 7,349 babies!
A few years ago the AARP published an article describing a woman looking back with sadness and regret at the babies she never had and never wanted. Planning ahead might avoid this situation.
Women always seem to be waiting for something – to complete an education, find a better job, loose 10 pounds, make more money, get a bigger or better apartment, or meet Mr. Perfect. Years can go by in the waiting game.
Even though she may be accomplishing much of what she dreams of, her eggs are aging. The expiration date of eggs is finite. Aging is the most significant factor influencing her ability to conceive. This waiting game is the biggest risk factor in a woman’s ability to conceive a child.
Women who merely assume their fertility will be there when they are “ready” present the greatest challenge. Most women aren’t even aware this is a problem. There seems to be little understanding of the biology involved. Women are born with their lifetime allotment of eggs (follicles) for reproduction. By the time a young woman has her first menstrual cycle between the age of 9-14, there are about 300,000-500,000 eggs. The average woman will ovulate for 35-40 years: 400-500 eggs (follicles) will be selected to ovulate (about one per month), but for every follicle that matures to the point of ovulation close to 1,000 others will be consumed in the process. The childbearing years are from 15-44. The average age of menopause is 51 years.
In the ten to fifteen years prior to menopause there is an increased loss of follicles, so that by menopause only a few hundred remain. The follicles that are left have decreased quality and capacity to mature. Many are not perfect: older eggs have a greater chance of being damaged with Down's Syndrome or other chromosomal abnormalities such as trisomies 13, 18 and 21. Additionally, the rate of spontaneous abortion (miscarriage) increases as a woman ages.
The human body is very efficient-it rids itself of pregnancies that are less than perfect, which occurs more frequently with older women and their older eggs. So the rate of miscarriage is closer to 50% in the 40’s compared to 20-25% in younger women. Also, as women get older they develop medical problems such as high blood pressure, diabetes, kidney and autoimmune diseases. These conditions can have a negative impact on the pregnancy and in turn, pregnancy can worsen the medical problem.
Men don’t have the same biology. They constantly produce sperm, which take approximately 70-80 days to produce from start to ejaculation. The sperm are always new.
Another issue with “aging eggs” is the use of donor eggs, which are eggs donated from a woman not older than 30-32 years. Fertility specialists usually recommend the use of donor eggs when the woman is over 42-43 to increase the chances of getting pregnant and carrying the pregnancy to term (live birth). Most women are open-minded about using donor eggs and some may also need donor sperm. Some women are not comfortable with the concept of donor eggs, even though they grow and mature the baby in their body.
Because of the increased risk of Down's Syndrome and other chromosomal abnormalities as a result of aging eggs, invasive testing is offered- CVS (chorionic villus sampling) is performed at 10-12 weeks and amniocentesis is usually done at 16-17 weeks. These tests are not mandatory. They are offered. They are a woman’s choice. They are both invasive and not without risk. The risk includes loosing what could have been a normal pregnancy. The risks should be balanced with benefits: weigh the need to know that the fetus is normal versus the risk of loosing the pregnancy. And consider your discomfort with finding out the fetus (your baby) has a serious medical problem, and the choices you will face.
I suggest planning ahead. Knowledge is the best way to avoid a perimenopausal pregnancy and the issues and risks they bring to women. The emotional roller coaster that a woman trying to conceive in her 40’s goes through with every passing menstrual cycle may engulf her in sadness.
For more information on midwifery, pregnancy or Elizabeth Stein CNM, MSN, MPH, please visit: www.AskYourMidwife.com.