Psychosis frequently occurs in women of childbearing potential who may have unplanned pregnancies. Understanding the risk of prenatal antipsychotic exposure can be of benefit in selecting therapies. The authors evaluated the in utero and lactation exposure effects of olanzapine, a novel antipsychotic that is used in treating schizophrenia, bipolar disorder, and other conditions and that may have expanded use in the childbearing population. All prospectively and retrospectively ascertained pregnancy reports were collected as a registry in the Lilly Worldwide Pharmacovigilance Safety Database. Outcomes were available from 23 prospectively ascertained olanzapine-exposed pregnancies. Spontaneous abortion occurred in 13%, stillbirth in 5%, major malformation in 0%, and prematurity in 5%, all within the range of normal historic control rates. There were 11 retrospectively ascertained cases of pregnancy. Two retrospectively ascertained cases of lactation exposure did not suggest infant risk. The early experience with olanzapine use in pregnancy and lactation is encouraging in that no obvious added risk to the fetus or infant was observed. Additional cases of pregnancy and lactation exposure need to be evaluated to determine whether these early findings are representative of the risks of olanzapine exposure to the fetus and infant. At this time, olanzapine should only be used during pregnancy and lactation when the potential benefit justifies the potential risk to the fetus or infant.