The Lindsay Clancy trial put ‘intrusive thoughts’ in the spotlight: Here’s what to know | Canada Voices

The trial of Lindsay Clancy, a Massachusetts mother accused of killing her three young children, has put the spotlight on a psychological phenomenon that is rarely discussed: intrusive thoughts of infant harm.

The notion that a new mother might imagine scenarios where her baby gets hurt is understandably disquieting; even more so when she pictures herself as the perpetrator. But current research suggests that such intrusive thoughts are incredibly common among new parents – and rarely ever acted upon.

Experts say the phenomenon is poorly understood, not just by the public, but health care providers as well.

Ms. Clancy’s high-profile trial ended in a deadlocked jury last month. It was livestreamed and obsessively discussed online – and has likely generated even more confusion, misunderstanding and fear.

To examine what the current science actually reveals about intrusive thoughts in the postpartum period, The Globe and Mail spoke with registered psychologist Nichole Fairbrother, a clinical associate professor with the University of British Columbia and director of the Perinatal Anxiety Research Lab. She is a leading expert on intrusive thoughts about infant-related harm – and is investigating what they actually mean for both the parent and child’s safety.

What are intrusive thoughts, and how common are they?

An unwanted, intrusive thought pops into your mind when you’re not expecting it. And that’s different from a worry, which is more of a verb – something we do and engage with. Whereas, an unwanted, intrusive thought will feel more spontaneous, like it’s happening to you. And these thoughts are inconsistent with a person’s beliefs, values and wishes.

We are seeing that about 99 per cent of new parents will report these thoughts of their baby being harmed by accident. ‘What if she falls off the change table while I’m changing her? What if I trip while carrying her down the stairs?’

And then, somewhere in the region of 50 to 55 per cent of parents in our samples will also report unwanted, intrusive thoughts of hurting their baby on purpose.

What does the research tell us about why these thoughts occur?

Unwanted, intrusive thoughts are common when we’re stressed, and the content is typically about things that we’re preoccupied with and things we don’t want to have happen. So, the theory is that we may have evolved to have not only thoughts of accidental harm, but thoughts of intentional harm, because they provoke in us some anxiety, distress and a desire to ensure that it doesn’t happen.

And we also know that these kinds of thoughts are most likely to happen when you are responsible for something that is precious and vulnerable.

How likely is it that a person with intrusive thoughts around harming their child might actually act on them?

So, we may not be at the end of the road in this research; there is some room to travel from here. But I have conducted two studies, where we looked at the prevalence of anonymously reported physical aggression toward babies among parents who reported these unwanted, intrusive thoughts of hurting their baby on purpose, and parents who didn’t have those kinds of thoughts.

What we found, consistently, was no difference in the risk of behaving aggressively. In addition, the raw numbers were a little lower for the group that had the intrusive thoughts of active harm. But we would need a very large sample – probably around 10,000 parents – to confirm if this is true.

Lindsay Clancy’s defence was that she was not criminally responsible because of postpartum psychosis. Many people may now be wondering if there is a relationship between intrusive thoughts and postpartum psychosis. What do we know about this?

An important thing to point out is that while the Lindsay Clancy trial has gotten us all to talk about this, it would be difficult to truly know anything about her. We’re seeing a court case; we’re not assessing her.

But it can be the case that in psychosis, a parent experiences thoughts of harming their infant. Postpartum psychosis affects one to two birthing parents out of every 1,000, and of those one to two people, maybe 5 to 7 per cent have some thoughts of hurting their infant. So, it’s really rare.

If that happens, it’s generally understood that the kinds of harming thoughts a person with psychosis would experience are what we call ego-syntonic. So, the person might not want them or like them, but they might, in the moment, believe that they are true. For example: ‘I need to drown my baby to make sure that she doesn’t get dragged into hell by the devil.’ There is an element of it being consistent with what you believe in the moment, even if that belief to the rest of us doesn’t make sense.

Whereas, if you talk to someone with obsessive compulsive disorder or someone having intrusive thoughts outside of psychosis, they will say, “This doesn’t make any sense. I don’t want to do this.”

And then, in the context of psychosis, it isn’t that uncommon for those thoughts to sound like voices or commands. And that is not the case in OCD or what we consider to be normally occurring unwanted, intrusive thoughts.

The defence is also arguing that Ms. Clancy first experienced unwanted, intrusive thoughts, before later hearing a command voice that instructed her to kill her children. Can intrusive thoughts escalate to the point where they become a command hallucination?

As people who work in this area, we’ve been having this conversation and looking at what data is available. Although there isn’t certainty around this, there isn’t any evidence to support the idea that a normally occurring unwanted, intrusive thought will develop into a psychotic delusion.

As an expert in this field, what has it been like for you to watch this trial unfold and the outsized attention it’s received?

For those of us who work in this area, it has probably raised some questions. What it has done more than raise questions, is make us very concerned that it has created a lot of unnecessary fear. I’ve had several new therapy clients come to me out of fear. ‘What if this happens to me?’ Agencies in British Columbia that I speak with regularly have also had an influx of people coming in.

Most new parents are not being taught about unwanted, intrusive thoughts of infant-related harm, and 54 per cent are experiencing them. So, before this trial, women were really afraid. They would often stay quiet for a long time, and we have anecdotal reports of people who became suicidal because of these thoughts. One woman attempted to give her baby up for adoption because she was so afraid of her thoughts.

So, my concern is that this trial happened before people were generally educated about intrusive thoughts, and now people are watching the trial, going, ‘Okay, well, I’m having intrusive thoughts. Am I going to be like her?’ All of the data would suggest it’s a pretty resounding ‘no’ to that question for the vast majority of people.

I’m really hoping that one of the outcomes is much broader education around what we actually do know about these intrusive thoughts, which is that we have no evidence that they are dangerous.

This interview has been edited and condensed.