The murder trial of Lindsay Clancy, a former nurse accused of strangling her three young children, has highlighted significant gaps in research and understanding of postpartum psychosis, according to experts and advocacy groups. The condition, which researchers estimate affects one to two per 1,000 women after delivery—equivalent to about 3,600 US mothers each year—remains poorly understood by both medical professionals and the general public.
Trial details and mistrial declaration
Clancy's defense attorneys argued she was suffering from postpartum psychosis at the time of the alleged killings, citing symptoms including anxiety, insomnia, and depression. She had received inpatient treatment at McLean Hospital, was prescribed psychiatric medications, and had searched for terms such as “psychosis” on her computer. Prosecutors, however, contended that Clancy was a deliberate killer who sent her husband out for errands to carry out the attacks.
On 4 September, Judge William Sullivan declared a mistrial after the jury remained deadlocked despite deliberating for more than a week. The case has drawn widespread attention, with supporters of Clancy reacting visibly in the courtroom as the judge addressed the proceedings on 20 August 2026, in Plymouth, Massachusetts.
Expert insights on postpartum psychosis
Kristina Delaney, founder of the non-profit advocacy group Cherished Mom, shared her own experience with the illness. Five months postpartum, her husband noticed her “hyperactive” speech and later found her rocking their children while saying, “‘Please save us, please save our family.’” Delaney, a registered nurse, said she spent two weeks in a psychiatric unit, “literally battling for my mind and my life.”
“It should not take a tragedy to start talking about postpartum psychosis and here we are – it’s outrageous it has become a viral topic after lives are lost and in a courtroom surrounding Lindsay Clancy,” said Delaney.
Jessica Heron, a psychologist and chief executive at Action on Postpartum Psychosis, a Swansea, Wales-based advocacy group, emphasized the severity of the condition. “Women have lost touch with reality at the point when they’re caring for a vulnerable baby, so the risks to the baby are high,” she said. “It has to be taken seriously – that’s why mother and baby care is so important.”
Rarity of infanticide and research challenges
Despite the risks, infanticide remains incredibly rare, even among women with postpartum psychosis. In the UK, there are roughly 1,200 cases of postpartum psychosis per year, with “a few cases per decade” of infanticide, according to Heron. In the US, epidemiological estimates put the rate at one to two cases per 1,000 deliveries, while infant homicide rates are 7.11 per 100,000, according to the Centers for Disease Control and Prevention (CDC). Women with the condition are at higher risk of harming themselves.
Dr Veerle Bergink, director of the Women’s Mental Health Center at Mount Sinai Hospital in New York, criticized the lack of education and classification. “We’re really in the middle ages here,” she said. “The Lindsay Clancy [trial] shows how ugly it gets with social media and people saying all kinds of things about postpartum psychosis, because they are not educated on it, because medical doctors do not learn about it, gynecologists or psychologists – because it does not exist in classification systems.”
Adding a new diagnosis to the Diagnostic and Statistical Manual of Mental Disorders (DSM-V) is a rigorous process. Many proposals are submitted each year, requiring evaluation by committees of expert editors. The last update involved more than 200 experts working across four key topics, including Dr Kimberly Yonkers, chief of the Yale New Haven Health Division of Psychological Medicine and lead of the gender study group for revisions.
“I think everybody agrees there’s something here,” said Yonkers. “There needs to be some attention to how this fits in the manual, what the criteria should be, where it should be. It’s a pretty rigorous scientific approach to the addition of a new diagnostic category. People are not always happy with that.”
Historical context and treatment prospects
The absence of postpartum psychosis from the DSM creates a circular problem, according to Bergink and advocates. Without a formal entry, funding for research, education for providers and families, and improvements in care are all difficult to achieve. Bergink described postpartum psychosis as one of psychiatry’s “strongest phenotypes,” with rapid onset often affecting women with no history of mental illness.
“It’s an illness that’s been reported since ancient Greek times,” said Heron. “There are so many historical reports of this very sudden dramatic illness happening after childbirth that it feels shocking that we still know so little about it.”
Despite these gaps, postpartum psychosis is highly treatable. Response to treatment with lithium and electroconvulsive therapy “is excellent,” according to a research review in Biological Psychiatry, in which Bergink was a co-author.
The trial echoes past cases, such as Andrea Yates, who was accused of drowning her five children in 2001 and was initially convicted of murder. Her conviction was overturned due to false testimony, and in 2006 she was found not guilty by reason of insanity. That case led to a legal fund now overseen by Postpartum Support International, which also supports inclusion in the DSM.
“There’s a lot of things the trial is pointing out – the inconsistencies, the lack of diagnostic criteria, certainly the lack of awareness, the gaps in the healthcare system – that I hope that we are not only pointing out through this trial but somehow we can move forward and expect change, and that this conversation does not stop, because it can’t,” said Delaney.
