Unfortunately for some women, the decision to have a baby does not come so easy. There are several things that can hinder a woman from easily conceiving a baby, and at times it takes medical intervention to help her achieve a successful pregnancy. However, according to new research, babies conceived through certain fertility treatment techniques are about one-third more likely to have a birth defect than babies conceived without any extra help from technology.
The researchers, whose findings were published in the journal Fertility and Sterility, did not determine why fertility treatments are tied to a higher risk of birth defects or whether the technology is even responsible, yet simply determined that there is definitely a greater risk.
One fertility option available is called In Vitro Fertilization (IVF). This procedure involves taking the mother’s egg outside of her body, fertilizing it, and then transferring it back into her womb. It has been available to would-be mothers for more than three decades, yet numerous studies have looked at the potential hazards of these techniques.
For this recent study, a team led by Zhibin Hu at Nanjing Medical University, reviewed 46 studies in which the number of birth defects in IVF babies was compared to babies conceived naturally. Of the over 124,000 babies born via IVF or ICSI, birth defect risks were 37% greater than in other children, wrote Reuters. ICSI involves fertilization of an egg via injection of a single sperm and has long been the main method used to overcome male infertility. If successful fertilization occurs, the embryo is then placed into the female via IVF. Fertilization, not necessarily pregnancy, rates are relatively high when ICSI is employed.
“Children conceived by IVF and/or ICSI are at significantly increased risk for birth defects, and there is no risk difference between children conceived by IVF and/or ICSI,” the team wrote, said Reuters.
The U.S. Centers for Disease Control and Prevention (CDC) notes that major birth defects occur in about three of every 100 babies born in the U.S. A 37% increase would raise this to four of every 100 babies, noted Reuters. Birth defect risk was seen across a span of functions and body systems, such as the genitals, skeleton, digestive system, and nervous system, the authors wrote.
“(The report) confirms what most people accepted anyway, that, yes, there is an increased risk in congenital abnormality associated with assisted reproductive technology,” said William Buckett, a professor at McGill University, according to Reuters. Buckett was not involved with the review.
The question of why most studies find birth defects to be more common among IVF-conceived babies, though, remains to be answered.
It’s possible that the same reasons people have trouble conceiving and seek out fertility treatment could influence their increased risk of having a baby with a birth defect.
It’s also possible that the IVF techniques themselves, the jostling and handling of the embryos, or the drugs that go along with fertility treatment, could be involved.
A third theory is that birth defects only appear to be more common in babies conceived through fertility treatments because they’re monitored more closely than other babies, Buckett said.
“Couples who have had babies born as a result of IVF are followed up more closely, and therefore subtle abnormalities may be detected that otherwise might not have been detected.”
As far as trying to reduce the risk of birth defects for parents using IVF, Hu said in an email that “it is really too early to find out ways to reduce the risk, because the reasons accounting for the risk are largely unknown.”