I crowded into a tiny observation room with the parents of all the other children in a gymnastic class, and couldn't help but glance around myself and take note of the different characteristics of the parents there. The ages of the parents seemed to range from early 20s into mid-to-late 40s. I was admittedly surprised to see some of the older parents. I know that our society is moving towards later marriages and later parenting, but is it really getting that late? How much potential does advanced maternal age have for resulting in adverse pregnancy results outcome? In other words, when is the expiration date for a woman's eggs?

While most psychologists and parenting experts would agree that most people are not truly ready to raise children until their late 20s or early 30s, it seems a woman's body does not agree. A woman's fertility is at its peak in her early 20s. It is at this time of life when she is most likely to conceive a baby and carry it to the term successfully. For women at this point of life also tend to have shorter, easier laborers that result in low risk vaginal births more often than older women.

Studies have indicated women in their early 20s have an average of a 25 percent chance of conceiving during any given month. These chances dip once she turns 27. Between the ages of 27 and early 30s, a woman's chance of conceiving during any given month reduces to only 15 percent, and once she reaches 35, her chances dip below 10 percent. Chances of conception, however, are not the only consideration when it comes to maternal age and its implications on pregnancy. Researchers have found later maternal age is strongly linked to pregnancy loss. Though all women are at risk of adverse pregnancy outcomes including spontaneous abortion, stillbirth and ectopic pregnancy, the chances of experiencing the most common, which is spontaneous abortion or miscarriage, is less than nine percent for mothers between the ages of 20 and 24. Once maternal age is beyond 45, the chances of experiencing an miscarriage increased to nearly 75 percent. These conclusions indicate advanced maternal age is a serious risk factor for difficulty conceiving and pregnancy loss.

Source: Andersen, Anne-Marie, et al. Maternal age and fetal loss: population based register linkage study, BMJ, 2000 June 24, 320(7251): 1708-1712.