A judge declared a mistrial on Friday after a jury failed to reach a verdict in the trial of Lindsay Clancy. The former Massachusetts labour and delivery nurse was accused of strangling her three children, slashing her wrists and throat, and jumping from a second-story window of her home in 2023.

Prosecutors argued that Clancy had the capacity to appreciate the wrongfulness of her actions and could follow the law. Her attorney contended she was not criminally responsible because she was experiencing postpartum psychosis, a rare mental health condition. Following the birth of her youngest child, Clancy had sought help from mental health professionals and taken several medications for mental health problems, according to her providers.

Postpartum mental health conditions

Mental health issues affect as many as 1 in 5 women in the United States during pregnancy and the year after birth, and are the leading underlying cause of pregnancy-related death in the country.

Postpartum psychosis

Postpartum psychosis affects up to 2 in every 1,000 women after childbirth. Symptoms typically emerge between two weeks and a year after birth, with 90% of episodes occurring within four weeks. Symptoms can include:

• Irritability, moodiness, and restlessness
• Insomnia and delusional beliefs
• Auditory or visual hallucinations
• Confusion, dysregulation, or depersonalisation

Untreated postpartum psychosis carries a 4% increased risk of infanticide and a 5% increased risk of suicide. Dr Nicole Leistikow, clinical director of the Johns Hopkins Reproductive Mental Health Center, noted that while screening tools exist for postpartum depression and anxiety, there is no specific tool to identify postpartum psychosis.

Other conditions

• Maternal depression: Affecting about 1 in 7 women, this is classified as major depressive disorder.
• Maternal anxiety: Affecting about 1 in 5 women, this can include extreme worry, sleeplessness, and a racing heartbeat.
• Baby blues: A temporary condition affecting about 80% of people who give birth, involving strong emotions such as sadness or frustration.