Cobie Smulders has battled ovarian cancer.

The former 'How I Met Your Mother' star was diagnosed with the potentially-fatal disease when she was just 25 years old and secretly underwent numerous surgeries in the two years that followed.

She recalled: ''I had tumours on both ovaries. and the cancer had spread into my lymph nodes and surrounding tissues.''

The 33-year-old actress - who has five-year-old daughter Shaelyn and a three-month-old son with husband Tarran Killam - admits she doesn't ever think she'll feel free of the disease, but wants to use her experiences in a positive way and help raise awareness of ovarian cancer, which killed around 14,000 women last year.

She told the May issue of Women's Health magazine: ''I don't think I'll ever feel like I'm cancer-free. Now that I'm five years out, I'm trying to think of it as a positive thing and what can I learn from it. And if I can create more awareness, I'll do it.''

Cobie has posed topless for the cover of the publication, and agreed to do so to prove how confident she is about her body, rather than to appear sexy.

She said: ''It was my first topless photo shoot where I wasn't trying to appear 'sexy', which was interesting.

''Because it's a women's magazine, I feel like being topless is more about being confident and about being happy with your body rather than trying to excite somebody else. That's what this cover was more about.''