Good news for couples who may be contemplating in-vitro fertilization (IVF) or other high-tech fertility treatments: The majority of children conceived by ART grow up completely healthy and normal, according to a new long-term study presented February 21, 2010, before an annual meeting of the American Association for the Advancement of Science.
"Overall, these children do well," says researcher Andre Van Steirteghem of the Brussels Free University Center for Reproductive Medicine in Belgium, in an interview with the Associated Press (AP) via the Chicago Tribune."It is a reassuring message, but we must continue to follow up."
On the down side, researchers note that ART children did appear at greater risk for rare neural tube defects and being low birth weight, a problem associated with obesity, hypertension, and type 2 diabetes later in life. Researchers also found a 5 to 10 percent difference in chromosome activity levels between ART and naturally conceived kids. (Abnormal chromosome activity may cause genes to behave in different ways, leading to such problems as an abundance of fat tissue or problems with blood glucose.) What is still not clear is whether these differences result in some way from ART or if they stem from other underlying factors, perhaps ones that caused the couple's infertility in the first place.
Risk for low birth weight among ART babies, researchers believe, is most likely the result of multiple-birth pregnancies (because twins and multiples tend to be delivered before their due date). "We must reduce the epidemic of multiple births," says Van Steirteghem in his AP interview. He also notes that in Sweden, the rate had been cut from around 30 percent in the early 1990s to about 5 percent today.
According to the AP, the use of single-embryo transfers in IVF is increasing in the US, resulting in a drop in triplet births to below 2 percent. This study also makes it clear that women undergoing IVF should take a daily 400 microgram folic acid supplement as a preventative measure against neural tube defects.