Embryofetal death has been observed in rats and rabbits receiving oral doses equivalent to 0.32 and 3.4 times the maximum recommended human dose (MRHD), respectively. No teratogenic effects were observed in rats and rabbits receiving this drug during organogenesis at an oral doses equivalent to 1.3 and 13-times the MRHD. Administration of nonsteroidal anti-inflammatory drugs (NSAIDs) during the third trimester of pregnancy may cause significant adverse effects, including premature closure of the fetal ductus arteriosus, oligohydramnios, fetal renal impairment, cardiopulmonary toxicity platelet dysfunction, pulmonary hypertension, and gastrointestinal or intracranial bleeding. 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.

Based on NSAIDs mechanism of action, use of NSAIDs in females may delay or prevent rupture of ovarian follicles, which has been associated with reversible infertility in some women. In male rats, decreased sperm count and motility, and histopathological evidence of testicular degeneration was observed when 0.3 times the MRHD was administered for 35 days.

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 Not Assigned: The US FDA has amended the pregnancy labeling rule for prescription drug products to require labeling that includes a summary of risk, a discussion of the data supporting that summary, and relevant information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy. Pregnancy categories A, B, C, D, and X are being phased out.

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

AU TGA pregnancy category: C
US FDA pregnancy category: Not assigned

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.

See references

Benefit should outweigh risk

Excreted into human milk: Unknown
Excreted into animal milk: Yes

Comments:
-The effects in the nursing infant are unknown.
-Some authorities advise against use due to lack of safety data in humans during lactation

Due to lack of published clinical experience during breastfeeding, other agents may be preferred. This drug has been found in the milk of lactating rats at concentrations higher than those in plasma.

See references