Advanced Maternal Age         

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The topic of “advanced maternal age,” technically referring to a pregnancy where the mother is expected to be > 35 years old at the time of delivery, is somewhat irrelevant today. Thirty-five years old was picked as the cutoff age for “advanced maternal age” somewhat arbitrarily, as the age at which procedural risk of amniocentesis roughly equals the risk of aneuploidy. Improved screening techniques, including first trimester screening, have largely dismissed concern about pregnancy at or after the age of 35, as invasive testing is offered to all mothers, regardless of maternal age. In fact, one in five women today deliver their first child after the age of 35. That said, there are still some risks that increase with age of which your patients should be made aware.

 

 

Risks with Increase of Age

 

At age 25, a woman has about a 1-in-1,250 chance of having a baby with Down syndrome.

At age 30, a 1-in-1,000 chance.

At age 35, a 1-in-400 chance.

At age 40, a 1-in-100 chance.

At 45, a 1-in-30 chance.

At 49, a 1-in-10 chance.

In addition to Down syndrome, the baby is at increased risk for many other chromosomal abnormalities; the trend is similar to that of Down syndrome – increasing incidence with increasing age. Often, these are lost as miscarriages.