Prozac in Pregnancy Tied to Lower Birth Weight

OB/GYN News, Dec 15, 1999 by Doug Brunk

Infants exposed to fluoxetine during the third trimester may have lower birth weights, while drug effects and withdrawal symptoms may occur in some neonates whose mothers take antidepressants near term.

These are among the findings revealed in a review of studies examining the effects of pharmacologic treatment of depression during pregnancy.

Dr. Katherine Wisner of Case Western University, Cleveland, and her colleagues conducted a search of MEDLINE and Health STAR for studies published from 1989 to 1999 in which maternal and infant health outcomes were compared with those of non-teratogen--exposed controls. Four studies met the criteria.

Investigators organized the data into five areas of reproductive risk: intrauterine fetal death, morphologic teratogenicity, growth impairment, behavioral teratogenicity, and neonatal toxicity (JAMA 282[13]:1264-69, 1999).

Exposure to tricylic antidepressants, fluoxetine (Prozac), or newer SSRIs such as fluvoxamine and paroxetine did not increase the risk of intrauterine death or major birth defects.

One study identified lower birth weights in infants exposed to fluoxetine, while the behavioral teratogenicity of children whose mothers took tricyclics and fluoxetine during gestation did not differ from that of controls. No data about the effects of the newer SSRIs on behavioral teratogenicity are available, the authors noted.

In another study, women who continued to take fluoxetine into the third trimester gained an average of 3 kg less than those who did not take the drug after 25 weeks' gestation.

They emphasized that "complementary clinical studies will determine whether poor maternal weight gain is due to fluoxetine or depressive symptoms that either do not or only partially respond to fluoxetine."

As for neonatal toxicity direct drug effects and withdrawal syndrome occurred in some neonates whose mothers took tricyclics, fluoxetine, and SSRIs near term.