Contraindicated last trimester of pregnancy
NSAIDs should be avoided at 20 weeks gestation and later

AU TGA pregnancy category: C
US FDA pregnancy category: D (third trimester); C (first and second trimester)

Risk Summary: Nonsteroidal anti-inflammatory drugs (NSAIDs) use in pregnant women at 30 weeks gestation and later may cause premature closure of the fetal ductus arteriosus; NSAID use at 20 weeks gestation or later may cause fetal renal dysfunction leading to oligohydramnios and, in some cases, neonatal renal impairment.

Comments:
-NSAID use in pregnancy prior to 20 weeks gestation should be based on a benefit-risk assessment; some authorities recommend avoiding NSAIDs throughout pregnancy whenever possible.
-If NSAID use is necessary between 20- and 30-weeks' gestation, limit use to the lowest effective dose for the shortest duration possible; ultrasound monitoring of amniotic fluid should be considered if NSAID use extends beyond 48 hours; if oligohydramnios occurs, discontinue NSAID and treat appropriately.
-NSAID use is not recommended in women attempting to conceive as it may impair female fertility.

Animal studies have revealed reduced weight gain, adhesions, peritonitis, hemorrhagic enteritis, gastric bleeding, and death in fetuses of rats at doses 5 times the maximum recommended human dose (MRHD), based on a mg/m2 body surface area. Additionally, pre- and post-implantation losses in animal studies have been shown. Administration of NSAIDs during the latter part of pregnancy may cause premature closure of the fetal ductus arteriosus and prolong labor and delivery. There are no controlled data in human pregnancy.

US FDA Drug Safety Communication (10-2020): The FDA is requiring a new warning be added to NSAID labeling describing the risk of fetal kidney problems that may result in low amniotic fluid. The FDA is recommending pregnant women avoid NSAID use at 20 weeks gestation or later. Through 2017, the FDA has received 35 reports of low amniotic fluid levels or kidney problems in mothers who took NSAIDs while pregnant. Five newborns died; 2 had kidney failure and confirmed low amniotic fluid, 3 had kidney failure without confirmed low amniotic fluid. The low amniotic fluid started as early as 20 weeks of pregnancy. There were 11 reports of low amniotic fluid levels during pregnancy and the fluid volume returned to normal after the NSAID was stopped. The medical literature has reported low amniotic fluid levels with use of NSAIDs for varying amounts of time, ranging from 48 hours to multiple weeks. Complications of prolonged oligohydramnios may include limb contractures and delayed lung maturation. In some postmarketing cases of impaired neonatal renal function, invasive procedures such as exchange transfusion or dialysis were required. In other cases, the condition was reversible within 3 to 6 days of stopping the NSAID and in these cases reappeared when the same NSAID was restarted.

NSAIDs may delay or prevent rupture of ovarian follicles which has been associated with reversible infertility in some women. The withdrawal of NSAID therapy should be considered in women with difficulties conceiving or who are undergoing investigation of infertility.

AU TGA pregnancy category C: Drugs which, owing to their pharmacological effects, have caused or may be suspected of causing, harmful effects on the human fetus or neonate without causing malformations. These effects may be reversible. Accompanying texts should be consulted for further details.

US FDA pregnancy category C: Animal reproduction studies have shown an adverse effect on the fetus and there are no adequate and well-controlled studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

US FDA pregnancy category D: There is positive evidence of human fetal risk based on adverse reaction data from investigational or marketing experience or studies in humans, but potential benefits may warrant use of the drug in pregnant women despite potential risks.

See references

In 6 women receiving treatment for up to 52 days, drug concentrations in breast milk were found to be about 1% to 3% of the maternal concentration. A separate study in 4 women receiving 20 mg per day showed nursing infants would be expected to receive an estimated 3.5% to 6.3% of the weight adjusted maternal dose. In separate reporting, 5 older infants remained healthy when nursed by mothers receiving 20 mg once daily for at least 4 months. Due to lack of published clinical experience in newborns, shorter acting agents may be preferred.

UK: Use is not recommended
AU and US: Use is not recommended unless potential benefits outweigh any potential risks.

Excreted into human milk: Yes

Comments: The effects in the nursing infant are unknown.

See references