Kirstie Allsopp had the same morning sickness as Kate

Who could fail to be cheered by the news that the Duchess of Cambridge is expecting her third child? But while I am delighted for Kate, I am also overcome by another emotion: admiration, tinged with a smidgen of trepidation.

Because Kate and I share something in common – a bond I would not wish on my worst enemy. Hyperemesis gravidarum (HG), or extreme morning sickness, is a hideous condition we have both been afflicted by.

The Palace has already announced that Kate is once again suffering HG – just as she did when expecting Prince George and Princess Charlotte – so she knows only too well what a rocky road she has ahead of her.

Who could fail to be cheered by the news that the Duchess of Cambridge is expecting her third child? But while I am delighted for Kate, I am also overcome by another emotion: admiration, tinged with a smidgen of trepidation

Which makes it all the more admirable that she is prepared to go down it again.

For make no mistake, HG is a horrible illness. I was stricken badly when expecting my second son Oscar in 2007. To call it extreme morning sickness is something of a misnomer. The debilitating condition bears little relation to the general queasiness most expectant mothers experience. I would even go so far as likening it to the awful sickness experienced by cancer patients undergoing chemotherapy – which I have witnessed first hand as my late mother endured three rounds of chemo for her breast cancer.

When I had HG, I could do nothing – and I do mean nothing. You can’t eat, you can’t go out, you are bedridden and desperate. If you become dehydrated you end up in hospital, which is exactly what happened to me in January 2007 when my partner Ben arrived home to find me in bed, disorientated and with a grey pallor.

During the six weeks I suffered I lost a stone in weight and was permanently exhausted. I couldn’t sleep, because I was being sick so often, and I became fearful of being left alone in case I knocked myself out while being sick.

I was so weak I could not even pick up my first-born son Bay, then one. All I could do was lie in bed. But I was lucky; I had a loving, supportive partner and we also had our wonderful nanny Heather, who is still with us.

Kate, like me, has a terrific support network. She has a great nanny, domestic help, a caring husband and the sort of job that can be put aside when necessary. But in one respect Kate is no different from the rest of us, and no amount of wealth or privilege can buy her the one thing I am sure she will want: to be well enough to take Prince George to his first day at Thomas’s School in Battersea on Thursday.

Because Kate and I share something in common – a bond I would not wish on my worst enemy. Hyperemesis gravidarum (HG), or extreme morning sickness, is a hideous condition we have both been afflicted by

Because Kate and I share something in common – a bond I would not wish on my worst enemy. Hyperemesis gravidarum (HG), or extreme morning sickness, is a hideous condition we have both been afflicted by

The Royal Family have not released any details of how badly Kate is affected – and some practitioners believe HG does improve with each successive pregnancy –but we know she is ill enough to have pulled out of a planned engagement to a children’s centre in London yesterday.

And if Kate feels anything like I did, it will take a miracle to get her to the school gates.

When I was at my worst I honestly think I would have struggled to get out of my house if it had been on fire. Being in a car, in particular, was awful. Can you imagine having to explain to your firstborn child why Mummy won’t be there to wave you off for your first day at school and marvel at how smart you look in your big-boy uniform? I bet Kate would happily swap the trappings of royal life to be fit for that important milestone.

Like Kate, who was hospitalised during her first pregnancy, I too became so ill I needed professional help. I can still vividly remember the heartache of being too unwell to celebrate my partner’s birthday. At the time my stepsons only stayed over one night a week and by happy coincidence that night was Ben’s birthday. We had a lovely meal out planned, but I simply could not go.

The experience had such an effect on me that I deliberately waited two years before trying for a third child –because I knew how hard it is to have a one-year-old and be debilitated. In my case that meant I was already 40 before Ben and I started trying for a third child, and unfortunately it never happened for us.

So Kate, I salute you. As I do really know what you are going through. I hope you feel better soon.

  • Kirstie Allsopp supports the charity Home-Start UK, helping families with young children. www.home-start.org.uk

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