Cradling her newborn son, Erin F. saw herself tripping and falling down the single step to her living room, knocking the scissors off the handrail. As the scene vividly played out in her mind, the shears stabbed through her arm into the infant she carried, killing him. (Erin asked WebMD not to use her last name because of the stigma that comes with mental illness.)

After that, the 41-year-old first-time mom feared stepping down stairs with her baby – any stairs. And for a while, she didn’t. But she couldn’t shake the feeling harm might come to her child somehow, and she needed to be vigilant about protecting him. 

She sewed tiny tracking devices into his shoes to prepare for a possible kidnapping and stashed choking rescue devices everywhere. She spent sleepless nights crying on the couch because she worried someone might rear-end them on the way to day care. And forget about going into the ocean – sharks were everywhere in her mind’s eye. 

OCD causes intrusive, repetitive, and often distressing thoughts along with compulsive behaviors that may relieve the anxiety around those thoughts.

Perinatal OCD  commonly causes thoughts of harm, illness, or death about the baby, says Neha Hudepohl, a reproductive psychiatrist in Greenville, SC. A mother also may check repeatedly to see if her infant is breathing or take other excessive measures, she says. “They may have a hard time being away from their baby or letting other people care for or hold their babies.”

Some studies show OCD may develop or worsen during the perinatal period in 17% of pregnancies, though much more study is needed to be sure. The odds are highest after childbirth, a biologically and psychosocially vulnerable period, says Lauren Osborne, MD, a reproductive psychiatrist with Weill Cornell Medicine New York Presbyterian Hospital.

The risk is higher in those with a personal or family history of OCD, anxiety, or depression, though some people get it without any prior history, Osborne says. Many people don’t get the care they need partly because they think they can’t take medication “for the sake of the baby,” Osborne says. But that’s not what doctors recommend. Mental health conditions are a common complication of pregnancy and childbirth and can be safely treated in most cases, she says. “[The] medications we use for depression, anxiety, and OCD during pregnancy are very low risk. And we know the illnesses themselves have a substantial bad effect on the baby and the pregnancy.”

Sometimes the obsessive thoughts may not even be about the baby. Ruth Zalta, 30, was diagnosed with perinatal OCD after crippling panic attacks that left her shaking convulsively and unable to sleep. Her obsessive thoughts revolved not only around her role as a mother, but also the possibility of death, the meaning of her life, and images of harming herself. 

Zalta’s doctor prescribed medication, including a selective-serotonin reuptake inhibitor (SSRI) which is generally considered safe during pregnancy and breastfeeding. Zalta also engaged in a type of evidence-based cognitive behavioral therapy with exposure and response prevention in which she surrounded herself with words and ideas that scared her.

She wrote words like “suicide,” “existence,” and “life” on sticky notes and placed them around her house, including above her daughter’s changing table and in her kitchen. “I would set alarms to engage in the exposure,” Zalta says. “And I became a little bit more desensitized and started realizing that just because I think something doesn’t mean I’m going to do anything.”

With treatment, Zalta felt much more in control by the time her daughter was born, and her symptoms haven’t returned in the 5 years since, including before or after the birth of her second child. And she now focuses her counseling work on OCD and perinatal mental health.

“At the time, my overall fear was what if I do something to leave my kids behind, and that still comes up now,” Zalta says. “But I realized I was stronger than I thought. That was very, very empowering and changed a lot for me.”   

Erin’s intrusive thoughts are still there, but she can sit comfortably with most of them. It helps that she’s given her son some tools to keep himself safe, including enrolling him in a self-rescue swim class.

“One thing that my therapist, my psychiatrist, and my doctor all told me was: You have a helpless toddler at home, so make him where he’s not helpless,” she says. “And I worry less knowing that if something happens and I look away for a minute, and he falls in the water, he’ll be OK and know what to do.”