County prosecutors charged former labor and delivery nurse Lindsay Clancy with first-degree murder and three counts of strangulation on Tuesday, after the alleged killing of her three children in Duxbury, Massachusetts. Clancy, who has pleaded not guilty, underwent a psychiatric evaluation before her arraignment. Clancy’s lawyer is arguing that the mother was not in the right state of mind at the time of the killing, citing “overmedication” for issues with maternal mental health.

Although there has been no official diagnosis yet, her defense attorney has suggested Clancy has a rare disorder called postpartum psychosis. A major symptom of the condition, which occurs once or twice among every 1,000 people who give birth, is that a person loses their sense of reality after pregnancy. 

People may develop postpartum psychosis quickly, immediately following the delivery or within the first week following birth, says Ariadna Forray, an expert in postpartum maternal mental health psychiatry at Yale School of Medicine. Although it can cause severe mental illness that, if left untreated, could potentially bring harm to the individual and others, Forray says “it’s rare for women to develop postpartum psychosis, and it’s even rarer to have women act out on their symptoms.” And while Clancy was reportedly taking treatments for postpartum depression, which is far more common, months before the killing, the condition itself is very different from postpartum psychosis.

What are the signs of postpartum psychosis?

People with the disorder show sudden mood fluctuations. One moment, they might feel jittery and highly energetic, and then the next moment, they may seem sluggish and more irritable than usual. “It’s your brain’s extreme reaction to having a baby,” explains Allison Lieberman, a marriage and family therapist who specializes in postpartum depression and psychosis at the online mental health platform Choosing Therapy. Chemical and hormonal shifts from childbirth, along with the stress of being a parent, can trigger a mother’s brain to have a “survival reaction,” she says.

Postpartum psychosis can be hard to recognize at first, because a mother’s physical and emotional changes often result from typical tasks like caring for a newborn baby. Parents rarely get much sleep in the first few months and often show dips in energy and appetite. 

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Specific risk factors associated with the condition are not well understood, because it’s so rare. But the most important symptoms to watch out for are confusion and disoriented thoughts that signal a loss of touch with reality. For example, parents may create delusions about the baby being sick when the child is perfectly healthy. They could convince themselves that the only way to help is to harm. “It’s the difference between knowing the intrusive thoughts are real versus not real,” says Lieberman. “Even if you think ‘I’m going to throw my baby down the stairs,’ that’s not necessarily psychosis if it disturbs you.”

However, both Lieberman and Forray stress that having postpartum psychosis does not automatically make you a violent person. In Lindsay Clancy’s case, the defense team is arguing she killed her children because a voice compelled her to do it. 

Is postpartum psychosis a symptom of postpartum depression?

No, they are unrelated to each other. The only connection is that both conditions occur after delivery. 

Postpartum depression is a medical condition where people who give birth experience intense feelings of sadness, hopelessness, and low mood within the first four weeks after delivery. Lieberman says it’s a longer and more intense version of the :baby blues,: because the condition interferes with a mother’s ability to care for themselves. “There’s this extra level of guilt that’s associated with not being able to be the parent you want to be and not enjoying parenthood,” Lieberman says. 

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Postpartum depression is common. It affects one in seven people who give birth, though many cases go undiagnosed because of the stigma and fear of being judged. Lindsay Clancy allegedly was taking 12 prescription drugs for multiple mood disorders, including postpartum depression. However, both Lieberman and Forray say it is not possible for postpartum depression to manifest into postpartum psychosis. 

While depression may cause new mothers to exhibit mood swings, postpartum psychosis is considered a type of bipolar disorder. “An estimated 70 to 80 percent of cases are related to bipolar disorder,” Forray says. Research suggests that having a history of the manic illness puts someone at a higher risk of developing postpartum psychosis after giving birth.

How is postpartum psychosis treated?

While delusions and hallucinations can take on many forms, the majority do not cause an individual to become violent. If there is evidence of postpartum psychosis in a patient, the best plan is to prevent the condition from worsening and avoiding escalation to acting out on these delusional thoughts. 

People with suspected postpartum psychosis need to be admitted to a psychiatric hospitalization where they can be assessed by a mental health expert, Forray says. Depending on the symptoms, they might then be prescribed medications such as a mood stabilizer or an antipsychotic. Another modern-day and safe alternative is electroconvulsive therapy. Research has shown the therapy helps to improve the severity of symptoms. “There’s a whole host of treatments that can be very effective,” Forray says. “And women start doing better as soon as treatment starts.”

With immediate medical intervention and the right support, it is possible to recover from postpartum psychosis. If you or someone you know is experiencing a mental health crisis, consider texting HOME to 741741 to reach the National Crisis Text Line or dialing 988 to the National Suicide Prevention Hotline. The services are free, confidential, and equipped with staff trained to get you the help you need.