Fertility: Based on the mechanism of action, the use of NSAIDs may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. In women who have difficulties conceiving or who are undergoing investigation of infertility, withdrawal of NSAIDs, including parecoxib (Dynastat), should be considered.
Pregnancy: There were no findings of teratogenicity in studies in rats and rabbits. Studies in rats at maternally toxic doses and studies in rabbits at the maximal evaluable dose have not revealed embryotoxic effects other than post-implantation loss, which has been observed with other drugs that inhibit prostaglandin synthesis.
There are no studies in pregnant women.
Parecoxib (Dynastat) should be used during pregnancy only if the potential benefit to the mother justifies the potential risk to the fetus.
As with other drugs known to inhibit prostaglandin synthesis, use of parecoxib (Dynastat) during the third trimester of pregnancy should be avoided because it may cause uterine inertia and premature closure of the ductus arteriosus.
Inhibition of prostaglandin synthesis might adversely affect pregnancy. Data from epidemiological studies suggest an increased risk of spontaneous abortion after use of prostaglandin synthesis inhibitors in early pregnancy. In animals, administration of prostaglandin synthesis inhibitors has been shown to result in increased pre- and post-implantation loss.
If used during second or third trimester of pregnancy, NSAIDs may cause fetal renal dysfunction which may result in reduction of amniotic fluid volume or oligohydramnios in severe cases. Such effects may occur shortly after treatment initiation and are usually reversible. Pregnant women on parecoxib should be closely monitored for amniotic fluid volume.
Lactation: Parecoxib (Dynastat) and its active metabolite are excreted in the milk of lactating rats. Administration of a single dose of parecoxib (Dynastat) to lactating women resulted in the transfer of a relatively small amount of parecoxib (Dynastat) and its active metabolite into breast milk, and this resulted in a low relative dose for the infant (less than 1% of the weight-adjusted maternal dose). Because of the potential for adverse reactions in nursing infants from parecoxib (Dynastat), a decision should be made whether to discontinue nursing or to discontinue the drug, taking into account the importance of the drug to the mother.