Reproductive Technologies and the Risk of Birth Defects

Robinson Institute, University of Adelaide, Adelaide, SA, Australia.
New England Journal of Medicine (Impact Factor: 55.87). 05/2012; 366(19):1803-13. DOI: 10.1056/NEJMoa1008095
Source: PubMed


The extent to which birth defects after infertility treatment may be explained by underlying parental factors is uncertain.
We linked a census of treatment with assisted reproductive technology in South Australia to a registry of births and terminations with a gestation period of at least 20 weeks or a birth weight of at least 400 g and registries of birth defects (including cerebral palsy and terminations for defects at any gestational period). We compared risks of birth defects (diagnosed before a child's fifth birthday) among pregnancies in women who received treatment with assisted reproductive technology, spontaneous pregnancies (i.e., without assisted conception) in women who had a previous birth with assisted conception, pregnancies in women with a record of infertility but no treatment with assisted reproductive technology, and pregnancies in women with no record of infertility.
Of the 308,974 births, 6163 resulted from assisted conception. The unadjusted odds ratio for any birth defect in pregnancies involving assisted conception (513 defects, 8.3%) as compared with pregnancies not involving assisted conception (17,546 defects, 5.8%) was 1.47 (95% confidence interval [CI], 1.33 to 1.62); the multivariate-adjusted odds ratio was 1.28 (95% CI, 1.16 to 1.41). The corresponding odds ratios with in vitro fertilization (IVF) (165 birth defects, 7.2%) were 1.26 (95% CI, 1.07 to 1.48) and 1.07 (95% CI, 0.90 to 1.26), and the odds ratios with intracytoplasmic sperm injection (ICSI) (139 defects, 9.9%) were 1.77 (95% CI, 1.47 to 2.12) and 1.57 (95% CI, 1.30 to 1.90). A history of infertility, either with or without assisted conception, was also significantly associated with birth defects.
The increased risk of birth defects associated with IVF was no longer significant after adjustment for parental factors. The risk of birth defects associated with ICSI remained increased after multivariate adjustment, although the possibility of residual confounding cannot be excluded. (Funded by the National Health and Medical Research Council and the Australian Research Council.).

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    • "Indeed, ICSI seems to be 'oversized' as first therapeutic approach to idiopathic infertile couples, especially in cases of (mild) oligozoospermia in the male and absent female factors. Furthermore, ICSI may increase the risk for congenital defects and not to forget that the necessary hormonal treatment regimen puts the health risk burden solely on the female partner (Davies et al., 2012). On the other hand, although the recent Cochrane review points to a beneficial effect, FSH treatment is ineffective in unselected idiopathic infertile men (Kamischke et al., 1998) since response to FSH differs between individuals due to the variety of underlying unknown aetiologies subsumed under the term 'idiopathic infertility' (Foresta et al., 2000). "
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    • "Another explanation for the observed zygosity differences might be fertility treatments, which generally produce DZ twins. It has been reported that parents of twins conceived via fertility treatments are better educated and are better off financially than those of naturally conceived twins (Burt & Klump, 2012; Davies et al., 2012). Due to the expenses of fertility treatments in many countries, these treatments would be more accessible to parents of a better socio-economic status (SES), which is in turn associated "
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