Background and Aim: Acetaminophen is routinely used during all stages of pregnancy for pain relief and lowering elevated body temperature. There is a little information about teratogenic effects of long term consumption of this drug. This study was designed to illuminate the teratogenic effects of the drug when taken before and during pregnancy.
Materials and Methods: 60 virgin female Balb/c mice were housed in an animal house with standard conditions, and were divided into 6 experimental groups (10 cases in each group). The first three experimental groups received orally 2800 mg/day of acetaminophen 10, 20 and 30 days before pregnancy
and during the 10 days of early pregnancy. The other 3 experimental groups received 5600 mg/day of the drug during the same periods as the first experimental groups. In contrast, the two control groups, routine and positive, received normal saline and base of drugs in the same manner as the experimental groups, respectively. For coupling, three males and one female were used overnight. After coupling was done under standard conditions and the vaginal plug was observed, zero time of GD was identified. The female mice were dissected on GD18th and the respective fetuses were collected. Macroscopic observation was done through Olympus SZX Japan stereomicroscope. The obtained data was recorded in the frequency tables and
analyzed by ANOVA and Tukey tests by means of SPSS software.
Results: This study showed that consumption of acetaminophen in the mentioned doses for 20 and 30 days before pregnancy and during the 10 days of early pregnancy can produce limb malformations such as limb deformity, reduction and asymmetry; and hand aplasia. Furthermore hemorrhage and absorption were seen in the fetuses.
Conclusion: with regard to the teratogenic effects of acetaminophen, it is recommended to avoid consumption of the drug for one or two months before pregnancy.