Reproductive Technologies and the Risk of Birth Defects
A new journal article in the May 10th issue of the New England Journal of Medicine has received a lot of coverage in the media. This article by epidemiology researchers in South Australia reported their findings correlating the reporting of birth defects up to the age of 5 in children conceived through assisted reproduction.
Overall, the authors reported that the rate of birth defects, after controlling for maternal age and other possible confounding factors such as maternal smoking, was increased 1.3 fold in children conceived with in vitro fertilization, GIFT and IVF with intracytoplasmic sperm injection (ICSI). In the case of children conceived via sperm injection (ICSI) the increase was 1.57 fold. For IVF without ICSI, there was no increase in birth defects. For babies born after frozen embryo transfer, there was only an increase in the children conceived via ICSI.
This article was interesting in that a large number of births were examined (total of 308,974 births, of which 6,163 were from assisted conception). And it is important that it followed children up to age 5. However, the findings were not novel and echoed what has been reported in several other prior studies. In fact the increased ratios reported in this study are actually lower than the ratios previously reported in many prior studies.
In the Journal Watch Womens Health, Dr. Robert Rebar, Executive Director of the ASRM said, Although these data are largely reassuring, one potential limitation lies in the identification and recording of birth defects, which has not been standardized; thus, the overall rates seem somewhat high. Another limitation rests in the use of data over such a long period, during which procedures in assisted reproductive technology improved rapidly and dramatically. These data reaffirm that couples with infertility have modest excess risk for having children with birth defects regardless of how or whether the infertility is managed. The possibility that risks are higher only when intracytoplasmic sperm injection is involved is biologically plausible, and could be related to the procedure itself or to genetic abnormalities found in some men with male factor infertility.
At Pacific Fertility Center, we have always tried to limit the use of ICSI to those patients that really truly need the procedure to achieve fertilization. Only when a significant male factor is present do we use it. However, this risk may have to be accepted by those couples needing ICSI that may otherwise be unable to achieve a biologic pregnancy.