Trying to Conceive After 35 – What are the Risks of Birth Defects?
Women all over the world have begun postponing motherhood for a wide variety of reasons. For some it has been the need to focus on a career and create financial stability, while for others it can simply be attributed to not meeting the right person. Even though it is perfectly normal for a woman over the age of 35 to take longer to conceive than a younger woman, the number of mothers over the age of 35 continues to rise. In fact, between 1978 and 2000, the National Center for Health Statistics stated that the birth rates for women aged 35 to 44 more than doubled.
One pressing question, which many women over the age of 35 have concerning the potential of becoming a mother at this age, is whether their unborn child will be at risk of a birth defect.
Age and Fertility
According to Web MD, age does play a major role in a woman’s fertility. Fertility is at its highest during a woman’s 20s. From the age of 23 to 31, a woman is at her most fertile. From then fertility declines by 3% each year until a woman turns 35. After 35, fertility begins to deteriorate quickly. By the age of 39, she will be half as fertile as she was at 31 and between 39 and 42 this is halved once again. The American Society for Reproductive Medicine concurs; stating that roughly one-third of all women aged between 35 and 39, as well as two-thirds of women over 40 years, have fertility problems.
Most women over 35 will have a perfectly healthy pregnancy, although they are subject to higher risks than other age groups. Most of these risks can be managed under a doctor’s supervision.
Women over the age of 35 are more likely to have children who are born with chromosomal abnormalities, such as Down Syndrome. At age 35, the risk of Down Syndrome is roughly 1/350, according to the Southern California Center for Reproductive Medicine. By the age of 40 the risk of a child being born with some sort of genetic abnormality is as high as 1/38. Women over the age of 45 are urged to be more careful with their pregnancies as the risk of having a child with a genetic abnormality skyrockets to 1/12.
During meiosis, when the egg cell eradicates most of its 46 chromosomes so that it can make way for the male’s genetic material, is when age-related chromosomal issues usually arise. Minute spindles work to separate the chromosomes. As a woman ages, these spindles become detached from the chromosomes, and it is this detachment that causes an abnormal number of chromosomes in the egg, which is otherwise known as aneuploidy. This commonly occurs in 33 percent of eggs at age 35, and at age 40, this percentage increases to 50 percent.
It is therefore recommended, by the American College of Obstetricians and Gynecologists (ACOG), that pregnant women who are older than 35 years should have prenatal testing to diagnose or rule out any chromosomal abnormalities. Approximately 95 percent of women who do have prenatal testing done, will find that their babies are perfectly normal. If the prenatal tests show no chromosomal defects, and the mother is otherwise quite healthy, then the likelihood of the baby being born with any birth defects at age 35, is not any worse than if the mother was in her 20s.
Non-chromosomal Birth Defects
After age 35, there is also a presumed increased risk of non-chromosomal birth defects and pregnancy complications. These include pre-eclampsia, gestational diabetes, and intrauterine growth retardation.
Reducing Your Risks
You can reduce pregnancy risks by seeing a doctor before trying to conceive so that your doctor can do a complete physical. This way you will be able to discuss any medical conditions and medications with your doctor.
Begin taking a daily prenatal supplement that contains at least 400 micrograms of folic acid at least three months before you start trying. Continue to take it through the first month of pregnancy to help prevent neural tube defects.
Nutritious foods should be a major part of your diet. Try to include foods that contain folic acid, such as in leafy green vegetables, oranges and orange juice, peanuts, fortified breakfast cereals, and enriched grain products.
Quit smoking or drinking alcohol excessively, before and after conception.