Television star Jessica Rowe has revealed the shocking depths of her postnatal depression, hoping her honesty will help women suffering as she did.

Rowe admits to "scary-obsessive" ideas after the birth of daughter Allegra in January last year.

I realised I wasn't a failure; what I had was an illness.  

"The small silver Tiffany & Co. clock that I used to time my breastfeeds became a weapon in my mind. I wondered how easily the clock could crack my baby's delicate skull," Rowe writes in the January edition of Vogue.

"My eyes would be drawn to the sharp carving knife in the second drawer in the kitchen. I wondered if such a knife could pierce my little daughter's soft skin.

"I knew I would never hurt my baby but these bizarre thoughts... kept going around in my mind."

Rowe - who is pregnant with her second child - told The Sun-Herald it was worth exposing the depths of her anguish if it helped even one woman.

While she put on a brave face after the birth of Allegra - a longed-for IVF baby - her dark thoughts spiralled out of control.

"I wrapped up the knife in newspaper and threw it away. I did this at night so the neighbours wouldn't see me," she writes. "I hid the silver clock, too, but even when these objects were out of sight they were still in my mind.

"Deep down I knew I needed help but I felt ashamed."

After six weeks of hell Rowe confessed to her husband, 60 Minutes reporter Peter Overton, she wasn't coping. "It was one of the hardest things I've ever had to do. I felt like I was letting him down too. He kept asking me if I was going to harm myself or Allegra. I told him of course I wasn't. But I knew I needed someone to pull me out of the anxious, frightening world my head was slipping into."

After an urgent visit to her obstetrician, Rowe was referred to a psychiatrist who diagnosed postnatal depression.

"I was keen to get started on antidepressants. I was desperate to get the thoughts out of my head," she writes. She noticed a slow change after three weeks. "That positive wind blew stronger over the following weeks, taking my dark thoughts away with it."

Rowe, a patron of Beyond Blue's perinatal initiative, writes: "I realised I wasn't a failure; what I had was an illness. It didn't mean I was a bad mother or that I didn't love my baby. I just needed some help to get over a difficult, dark patch."

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