Both ART and infertility raise birth defects risk

Although assisted reproduction has been associated with an increased risk of birth defects, the risk varies among methods.

Use of clomiphene citrate as a single agent at home was associated with a higher rate of birth defects than clinically managed induction of ovulation using any of several drugs.

Assisted reproductive technologies (ART) raise the risk for birth defects by about 28%-but so does infertility, a large observational study from Australia reports.

Researchers reviewed almost 309,000 births for birth defects. Of these, 6,163 involved ART. The multivariate adjusted odds ratio (OR) of a birth defect diagnosed before age 5 years in a child conceived through ART was 1.28 versus 1 from unassisted conception (95% confidence interval, 1.16-1.41).

For in vitro fertilization (IVF) alone, the OR after multivariate adjustment was 1.07, which was statistically insignificant, whereas that for intracytoplasmic sperm injection (ICSI) remained significant at 1.57 after adjustment.

Compared with births from spontaneous conception in fertile women, births from spontaneous conception in women who used ART with a previous pregnancy also had increased overall risk of any birth defect, even after adjustment for confounders (OR, 1.25) Further, a history of infertility without ART treatment was associated with an adjusted OR of 1.29.

Compared with clinically managed induction of ovulation with the use of any of several drugs, the use of clomiphene citrate as a single agent at home was associated with an increased risk of birth defects, as was using fresh- versus frozen-embryo cycles of IVF or ICSI.

Although significant associations between assisted conception and birth defects existed for singleton births, multiple births remained unaffected. The research was published in the New England Journal of Medicine (2012;366[19]:1803-1813).

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