You know someone who has, or has had, perinatal mental illness. You may not realise it, but you do. According to the campaign Everyone's Business, run by the Maternal Mental Health Alliance, more than one in ten women develop a mental illness during pregnancy or within the first year after childbirth.

When I was suffering from postnatal depression PND , friends were desperate to help. Sometimes they would ask me what they could do to help, but often they simply proactively did something that made a difference. I've often been asked by people how they can help someone going through the same thing. Here's some tips:

Help her to get out of the house

When my son was about four weeks old, I had barely left the house with him, other than for essential doctor's appointments, and for those I relied on my husband to accompany me. I was extremely anxious about going out. My cousin came to visit me and packed the change bag for me, going over everything I might need, and walked me to the café down the road. About a week later, a friend walked me to the park, reassuring me all the way, and helping me to have my first meet-up with a fellow new mum in doing so. I cannot stress enough how much getting out helped me. It's pretty simple: fresh air, sunlight, exercise and a change of scene.

Show you are there

But in a way which does not put pressure on her. That might be daily texts, or emails I found it very hard to deal with phone calls and couldn't easily commit to face to face meetings early on . It will help her connect with the outside world.

Send her things that will make her laugh and distract her

Even if she receives them in a bad moment, she can come back to it later. I loved getting things in the post. A friend sent me a very funny film of her mum and aunt on a recce for the TV show she was working on. I'm not suggesting these little moments combat serious depression on their own, but they do all contribute to the recovery process.

You might not know how she feels

That doesn't matter. What you do have is a friendship with her, and reminding her of that will help. Some of the best visits I had were from friends without children, who knew me well and came without judgement, and who recognised that yes, I was going through something very difficult. They didn't come pretending to have the answer.

1. If she tells you she has PND suddenly in conversation...don't recoil. Don't underestimate how hard it was for her to tell you. Even if you feel panicked and don't know how to help her, your first reaction is important.
2. Don't be offended if she cancels arrangements. There will be days when she can't face anyone, even you. That's not personal.
3. Show her proof she is not the only one. I can still remember the stories friends told me to show me that what I was going through, while horrible, was not unique, and they gave me strength. It could be sending an article about a celebrity like Hayden Panettiere or Brooke Shields who has spoken publicly of their experiences of PND. Or, it could be telling her that actually your sister had this and putting her in touch.
4. Help her access skilled support. Friends are fantastic, and played a big role in my recovery. And nothing should replace professional medical help. But there is a middle tier of support, from skilled organisations such as Bluebell and The Smile Group and national charities PANDAS and APNI. Point your friend in their direction, and help her get in touch with them.
5. Therapists and counsellors often support women with postnatal depression
6. Fine Not Fine : Perspectives and Experiences of Postnatal Depression published by Free Association Books
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