If you read the previous blog post, you may be scratching your head… because recent studies also have determined that the likelihood of birth defects is lowered by ART procedures, like in vitro fertilization and gestational surrogacy.
The likelihood of birth defects is typically higher in women who are older when pregnant. But a recent analysis of 300,000 births suggest that for older women, pregnancies conceived through ART methods as opposed to traditional conception are less likely to result in children with birth defects.
Previously, higher maternal age and the use of ART methods were both thought to be contributing factors to the presence of birth defects. Therefore, older women who conceived through ART were thought to be especially at risk for birth defects. A recent study, however, conducted by researcher Michael Davies at the University of Adelaide, Australia suggests otherwise.
The results of this study that examined births in South Australia from 1986-2002 found that older women who conceived through ART methods were less likely to experience birth defects that both older women conceiving through traditional methods, and younger women who conceived through ART methods.
One suggested explanation for these results is that the drugs used during the assisted reproductive process have a protective effect on older mothers’ eggs that does not have the same effect on younger women.
Another suggestion is that the likelihood of birth defects in older and younger women is actually the same, but the likelihood of an embryo surviving is lower in older women. Essentially, the births reported from older women would have already corrected for the likelihood of these defects because it’s less likely these embryos would have survived full term.
Davies is optimistic that the results from this study could have implications for how birth and fertility treatments are viewed, especially considering that the average age of a women during birth has been rising. But other researchers, such as Peter Illingworth of an Australian fertility company contends that these results will have to be further studied and validated before such implications can be drawn.
You can read more about these new findings at Newscientist.com.