It was supposed to be an exciting time. The new mother had just given birth at age 42, after a much-desired pregnancy. But within a week, she developed postpartum depression.

The medical condition — characterized by extreme sadness, anxiety or despair following childbirth — affects up to 1 in 5 women.

At five months postpartum, the woman was stuck in a haze, said Dr. Misty Richards, medical director of perinatal psychiatry at the Maternal Outpatient Mental Health Services Clinic at UCLA…