EXCLUSIVE: As Sex And The City's Sarah Jessica Parker admits she's expecting twins using a surrogate, we talk to Jacqui Shields, 42, who carried five babies for other women - and gave them all up...
I'd be a liar if I said it wasn't heartbreaking walking out of hospital without a baby after carrying it for nine months, because it is.
But being a surrogate mum is always a mixture of sadness and happiness, as I'm sure the lady carrying twins for Sarah Jessica Parker will discover.
Ultimately though, it's a positive experience and I feel privileged to have made a difference to so many couples' lives.
Not being able to have the baby you long for can be devastating, and I think Sarah Jessica, 44, and her film star husband Matthew Broderick, 47, are fantastic for going public about using a surrogate mum.
Some people are ashamed to admit they couldn't carry their own child, but it's not something to be embarrassed about.
I have three children, Rebecca, 20, Andrew, 18, and Annie, 16, from my first marriage, and I was sterilised a year after Annie, thinking my family was complete.
I'd always wanted to help childless couples by becoming a surrogate mother, and decided to help my first couple in 2001.
Luckily, having your fallopian tubes tied when you're sterilised doesn't stop you being able to carry a surrogate child, as the egg is fertilised in a test tube and then placed in your womb.
I was petrified, but excited at the idea of being a surrogate. I met the first couple, who were form Cambridge, and go to know them before agreeing to help.
The pregnancy went smoothly. But I was as sick as a dog for the first couple of months, as I always am when I'm pregnant.
At the time I thought to myself 'How stupid am I to go through this for somebody else?' But once I got to 12 weeks it was fine.
And morning sickness is just like giving birth-you soon forget about it. The mothers I carry for are always very curious about the whole pregnancy. So I try to make them feel they're part of it every step of the way and watch the bump grow with me. I hope Sarah Jessica has the same experience.
The first couple I carried for were so thrilled when we discovered I was having twins for them, as I'm sure Sarah Jessica and Matthew will be feeling right now.
I was overjoyed, too.
When I gave birth the mother was there, holding my hand. when the first twin was born she was in tears. She bent down and kissed me and said 'thank you' and she held the first twin while I pushed the other one into the world. It really was such an amazing experience.
The hospital and parents treated me like a queen. When you hand the child to the couple, it's mindblowing to see their faces, it makes it all worthwhile. The pain vanishes.
The hardest part came when I had to fill out some paperwork.
The nurses called me into a room where the twins were and they'd got their little coats on.
After walking out of the hospital I sobbed my heart out all the way home. It was like having my right arm chopped off.
I would say the first time was the hardest because I didn't know how I was going to feel. It got easier after that. Now I don't find it hard to separate myself from the baby after the birth.
I just think of myself as the oven. I've been given the ingredients, I bake it and then I give it back. I do call myself 'mummy' during the pregnancy, but I never think of any of them as mine. It's a weird mix of emotions and, to be honest, it's often the couple that you miss the most, after having had such close contact with them for so long.
You have to prepare yourself for after the birth. Some couples decide to cut off contact with the surrogate. That must be awful.
Some couples do it because they panic that the surrogate will want the baby or they don't want reminding that they couldn't carry the baby.
But I've been lucky and I'm still in touch with all my couples. They normally contact me every day for the first few weeks.
Hearing about sleepless nights and how knackered they are, while I'm getting fantastic sleep at my home in Winsford, Cheshire, makes it a lot easier! I got pregnant as a surrogate for the second time two years after the first, this time for a Scottish couple, and then came the third and fourth surrogacies.
But ironically by this point I was desperate to have another baby of my own.
After my first marriage fell apart, I met my second husband Joe, now 54, in 1997 and we really wanted to have a baby of our own.
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