Courtesy of Nanu Grewal in Australia, I’ve come across this interesting paper: Systematic meta-analysis of individual selective serotonin reuptake inhibitor medications and congenital malformations, by Nicholas Myles et al.
The authors note that there is some suggestion of a link between SSRI’s, as a group, and birth defects, but that the teratogenicity of individual members of this drug class have not been systematically compared by meta-analysis.
Meta-analysis is essentially a systematic review of previous studies and combining of the results of those that meet certain pre-determined criteria for research quality.
The search yielded 16 papers that looked for major malformations; 9 papers for specifically cardiac malformations; and 4 papers for minor malformations.
The study found that fluoxetine (Prozac) and paroxetine (Paxil) were associated with an increased risk of major malformations. Paxil was also found to be associated with increased risk of cardiac malformations.
The odds ratios (ORs) were:
The 95% confidence interval (CI) means that we can be 95% certain that the real value of the odds ratio (as opposed to the value found in the particular samples studied) falls inside the interval stated.
Odds ratio is the ratio between the odds of a malformation in the babies whose mothers took the drug versus the odds of a malformation among the babies of women who didn’t. If the risk of a malformation were the same for both groups, then the odds ratio would be 1. If the odds for the drugged group were twice that for the non-drugged group, then the odds ratio would be 2. The ratios found in this study ranged from 1.14 to 1.44, which given the human and financial cost of congenital malformations, are certainly not trivial.
One more reason to be wary of psychiatrists with prescription pads.
Incidentally, sertraline (Zoloft) and citalopram (Celexa) were not found in this study to be significantly associated with birth defects.