The foregoing is a case report about a 30-year-old woman, who was referred to our psychiatry clinic with a clinical picture of manic episode, at the 21st week of her first pregnancy. She had a history of bipolar affective disorder for 12 years, had two previous manic episodes and had stopped taking lithium 6 months ago because of her plans to become pregnant. Quetiapine was begun and the dose was slowly increased to 1200 mg/day after 2 weeks. She continued to receive quetiapine throughout her pregnancy. Her obstetrical and perinatal examinations were done by a consultant obstetrician. At the follow-up, she had given birth to a boy, at 39th week of her pregnancy, with an Apgar score of 10. Follow-up of the infant up to 3 months reveals normal physical and psychomotor development. The pros and cons of quetiapine use during pregnancy are discussed.