Caution is recommended.

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

Comments:
-There is no data on use in pregnant women to know this drugs risks, including the risk of fetal harm or reproductive effects.
-Acetaminophen is commonly used during pregnancy and has been assumed safe; recent data questions the safety, especially with routine use or varying genetics.
-Routine use of acetaminophen during pregnancy is not advised.
-Chlorpheniramine is considered by some authorities to have low gestation risk, however a possible association with retrolental fibroplasia has been seen in premature infants.

Animal studies are not available for the combination product. There are no controlled data in human pregnancy.

Acetaminophen: Routinely used during all stages of pregnancy, it appears safe for short-term use. This drug crosses the placenta.

Chlorpheniramine: A monitoring study of 50, 282 mother/child pairs (1070 first trimester exposures, 3931 any time pregnancy exposures) did not suggest a link to categories of major or minor malformations, however possible individual associated malformations were found (7 cases polydactyly in 272 blacks, 13 gastrointestinal defect cases, 7 cases of eye and ear defects, 22 inguinal hernias, 8 hydrocephaly cases, 16 congenital hip malformations, and 6 cases of female genitalia malformations). A 1971 study in which chlorpheniramine was the sixth most used antihistamine found fewer malformations in infants exposed to antihistamines in the first trimester. Antihistamine exposure during the last 2 weeks of pregnancy may be associated with retrolental fibroplasia in premature infants.

AU TGA pregnancy category A: Drugs which have been taken by a large number of pregnant women and women of childbearing age without any proven increase in the frequency of malformations or other direct or indirect harmful effects on the fetus having been observed.

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.

See references

Caution is recommended.

Excreted into human milk: Yes (acetaminophen) / Data not available (chlorpheniramine)
Excreted into animal milk: Data not available (chlorpheniramine)

Comments:
-The amount of acetaminophen in breast milk is much less than typical infant doses.
-One study calculated that infants receive about 0.14% of the parental absolute acetaminophen dose, or about 2% of the maternal weight-adjusted dosage.
-Occasional small chlorpheniramine doses during breastfeeding may be acceptable, but large doses or prolonged use may have adverse effects on the infant or decrease milk production, particularly in combination with pseudoephedrine or before lactation is established.

See references