The U.S. Centers for Disease Control and Prevention published a research study which found a link between the drug Clomid and a constellation of birth defects. Though the authors of the Clomid birth defect study voiced some reservations about the results of their study, they found evidence of birth defects not previously linked to Clomid.

Clomid (clomiphene citrate) is a drug used to treat specific types of infertility. Specifically, Clomid treats types of infertility where women do not release an egg cell, or do so infrequently or irregularly.

Clomid works by mimicking the hormones that normally trigger ovulation. Depending on the exact data referenced, Clomid may increase the chance of conception more than four-fold for some women. Studies like this suggest that Clomid may be linked to serious birth defects including skull defects, heart defects, brain defects and other birth defects.

The CDC’s Clomid birth defect study was published in November 2010. This was a population-based case-control study. This type of study finds a group of people and closely studies them, identifying risk factors and disease outcomes and figuring out what risk factors match up with what diseases.

The famous Framingham Heart Study involved a city in Massachusetts in which 5,209 residents received free medical testing in exchange for participating. The experiment has continued since the 1950s and is now on the third generation of participants, contributing much of what medical science now knows about heart health, cholesterol, and obesity.

Along similar lines, this CDC Clomid birth defect study used data collected by the National Birth Defects Prevention Study, which has gathered data from 30,000 women who had children with birth defects and 10,000 women with healthy babies as a control group to compare. The fact that the data was pulled from women and infants across America makes it more likely that the data applies to Americans.

Researchers in the Clomid birth defect study found that women taking Clomid were more likely to have children with a variety of birth defects. The study specifically mentioned nine dramatic birth defects, including conditions where some or even most of the skull and brain are absent (ancephaly) or the abdominal organs form exposed, outside of the body (cloacal exstrophy).

This was also the first study to specifically note a link between Clomid and a specific brain defect called Dandy-Walker malformation, as well as cloacal exstrophy, and a specific heart defect.

Researchers’ only reservation about their conclusions was that it was not possible to determine if Clomid was the risk factor itself or if there was a potential cofounder or second risk factor. Researchers put forward an alternative interpretation that infertility itself increased the risk for these birth defects. However, other studies have found a similar link between at least half a dozen of the listed birth defects and Clomid.

Additionally, the legal system has a different way of looking causal factors for birth defects than medical science. In some cases, this means a lower standard of evidence for the legal system. As such, a Clomid class action lawsuit investigation has been launched to explore the possibility of Clomid lawsuits for women who had children with alleged Clomid birth defects.