OCD is usually pictured as checked locks and repeated handwashing. Less well known is that it can appear, or sharply worsen, during pregnancy and in the months after a baby arrives.
A research review has examined this perinatal period specifically. It draws together evidence on how often OCD begins or intensifies during pregnancy and the postpartum, what may contribute to it, and how it can be treated. Both new cases and the worsening of existing symptoms were considered, alongside biological and psychosocial risk factors. That breadth reflects how much physical and psychological adjustment this period involves.
For some parents, perinatal OCD includes intrusive, unwanted thoughts about harm coming to their baby. These thoughts are distressing precisely because they run against everything the person wants. They are a recognised feature of OCD. They are not a sign of poor parenting, and they are not a warning that harm is likely.
The review also looked at treatment, including psychological therapy and, where appropriate, medication. Evidence in this area is still developing, so decisions are best made individually with a clinician.
If you are pregnant or newly parenting and your thoughts have become frightening, speaking with a psychologist or your GP is a reasonable next step.
Setting the scene: what this review actually is
This isn't a single experiment — it's a review paper, meaning the authors gathered and synthesised existing research on obsessive-compulsive disorder (OCD) occurring in the perinatal period (the stretch of time spanning pregnancy through the postpartum months). Reviews are useful because no single study tells the whole story; they let researchers spot patterns across many smaller studies, including both observational studies (where researchers watch what happens naturally, without controlling treatment) and randomised controlled trials, or RCTs (where participants are randomly assigned to a treatment or comparison group, which allows stronger conclusions about cause and effect).
OCD itself involves two linked features: obsessions (intrusive, unwanted thoughts, images, or urges that cause distress) and compulsions (repetitive behaviours or mental acts performed to reduce that distress, like washing or checking).
What the review found
The authors report that OCD, and milder 'subthreshold' obsessive-compulsive symptoms (present but not severe enough for full diagnosis), likely occur more often during the perinatal period than in the general population — though exact rates vary a lot between studies, reflecting how limited the evidence base still is.
Interestingly, the content of the symptoms tends to shift in this period. Compared to OCD at other times of life, perinatal OCD is more likely to centre on fears of harm coming to the child, alongside contamination fears, aggressive intrusive thoughts, and compulsions involving cleaning or checking. The review is careful to frame these as recognised clinical features, not evidence of parenting risk.
On causes, the picture is unclear: research into biological explanations (such as hormonal or neurological factors) is described as too limited right now to draw firm conclusions. Psychosocial factors are also discussed as relevant, though the review stresses that overall evidence in this area remains thin.
For treatment, the review finds consistent support — from both observational studies and RCTs — for cognitive behavioural therapy with exposure and response prevention (CBT with ERP), a structured therapy where a person gradually and safely faces feared situations or thoughts while resisting the urge to perform compulsions, allowing anxiety to reduce naturally over time. There's also some, more limited, evidence supporting selective serotonin reuptake inhibitors (SSRIs), a class of antidepressant medication. Importantly, the authors note that treatment approaches don't differ from those used for OCD generally — the evidence base specific to the perinatal period is simply sparser.
Why this matters, and its limits
Any decision about treatment during pregnancy or breastfeeding involves weighing the risks of treatment against the risks of leaving OCD untreated — a balance the review highlights as a key clinical consideration, without prescribing a one-size-fits-all answer.
The honest limitation here is that this is a young, patchy research area: prevalence estimates vary widely, causal mechanisms aren't settled, and perinatal-specific treatment trials are limited. What is clear is that perinatal OCD is common enough to matter, can be genuinely impairing, and looks somewhat different from OCD at other life stages.
If intrusive thoughts are frightening you during pregnancy or after having a baby, this is a known, treatable experience — reaching out to a health professional is a reasonable and worthwhile step.