Pregnancy outcome following fetal exposure to tiaprofenic acid in the first trimester.

Fetal exposure to nonsteroidal inflammatory drugs beyond the 34th week of gestation is theoretically associated with premature closure of the fetal ductus arteriosus due to the inhibition of cyclooxygenase. Inadvertent exposure to tiaprofenic exposure in the first trimester is of concern due to the paucity of prospective human data. Experiential data are limited to retrospective reports submitted to the manufacturer and animal data, the extrapolation of which to humans is very inaccurate. We report pregnancy outcome in 12 women who voluntarily contacted the Motherisk Program in Toronto about first trimester exposure to tiaprofenic acid. These women were older than women who generally contact Motherisk (30.6 years +/- 3.9 years versus 29.9 years +/- 3 years). Three pregnancies ended in first trimester miscarriages and one woman elected to terminate her pregnancy. Of the eight live births, the mean gestational age at delivery was 39.2 weeks +/- 2 weeks, the mean birthweight was 3359 +/- 503 gm, no malformations were detected, and age of attainment of developmental milestones was normal. Although 25% of exposed cases ended in miscarriages, this may not be statistically meaningful. However, a similar trend is documented in animal studies and should be borne in mind when counseling the pregnant patient.