UK: Use should be avoided.
US: Caution is recommended; benefit should outweigh risk.
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US FDA pregnancy category: D

Comments: If this drug is used during pregnancy, or if the patient becomes pregnant while taking this drug, the patient should be apprised of the potential harm to the fetus.

Animal studies have revealed embryonic resorptions. Atenolol has been shown to produce a dose-related increase in embryofetal resorptions in rats. In humans, atenolol administration starting in the second trimester has been associated with the birth of infants that are small for gestational age. Controlled data in human pregnancy exists only for atenolol in the second and third trimesters of pregnancy.

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

Use should be avoided.

Excreted into human milk: Yes (atenolol, chlorthalidone [chlortalidone])

See references