Sarah Davies, 33, tells her real life story:
I opened the front door, took a deep breath and said to my partner Owain: 'Sit down, I need to tell you something.'
His eyes widened and he said, 'You're getting rid of me, aren't you?'
I started to laugh.
'Don't be silly,' I replied. 'I was going to tell you I'm pregnant!'
I watched Owain's face register first relief, then delight.
He held me close and said, 'That's brilliant.'
Although we had only been a couple for six months, we'd been friends for years and the timing felt right.
We were both completely overjoyed- me especially.
At nearly 130kg, I had been worried that I'd struggle to get pregnant. For years, I hadn't used contraception and hadn't once had a scare that I might be expecting.
Deep down, I knew my weight was a factor.
All the medical advice I'd read recommended losing weight to have a baby and I'd worried about how I would manage that.
But now that I'd fallen pregnant without losing a single kilo, all my anxieties melted away.
I was having a baby despite my large size.
I started imagining what our little one would look like and planned out a nursery in my mind.
Then I imagined our child taking their first steps and eventually going to school.
The future stretched ahead of us and it was filled with wonderful family moments.
But then, when I was nearly eight weeks gone, something happened.
I woke up one morning with cramps in my tummy and when I went to the toilet I realised I had started bleeding.
I felt terrified.
I said to Owain: 'I'm going to lose this baby.'
He tried to reassure me and I went to the doctor in the hope I was mistaken.
But I wasn't.
'I'm so sorry,' the doctor said.
I put my face in my hands.
The doctor didn't say what had gone wrong. He didn't have to.
His expression, as he eyed up my rolls of belly fat, said it all.
Back at home, Owain did his best to comfort me.
'We can try again,' he said.
But I was devastated. As much as I told myself it just wasn't meant to be, in my heart I knew that my size was to blame.
My 130kg body had killed my baby and I felt so guilty.
For the first time, I hated my size. Although I'd always been a big girl, my weight had never bothered me before, and it had never held me back.
Now, however, it was a problem.
It took my body a few months to recover from the miscarriage and during that tough time, my emotions were all over the place.
I needed something positive to focus on and Owain gave it to me. He proposed.
It was just the tonic I needed to get back on track and we set a date for nine months' time.
I got busy planning and then I went shopping with a friend to choose a wedding dress. We were both really excited, but it soon became clear there was a snag.
The only dress in the shop that I liked was too small for me.
The assistant told me: 'You will need to lose at least 13kg to fit into it.'
But the shop owner insisted on weighing and measuring me, and made me sign a form to say I was going to lose the weight before she'd agree to sell me the frock.
As I walked home, I turned to my friend and said, 'But how am I going to do it?'
And then, as if by way of an answer, I saw a sign. It was for a weight loss club.
I pointed at it and said, 'I'm going to join.'
I went to my first meeting and listened to the group leader talking about a different way of living. She promised that I could eat lots, I'd never feel hungry and I'd still lose weight.
It sounded impossible, but I was ready to try just about anything.
At home, I totally changed my eating habits. Out went the sugary cereal for breakfast, the ham and cheese sandwiches for lunch and the takeaway burgers and pizzas for dinner.
Instead, I started the day with two Weet-Bix, had an omelette for lunch and made something from scratch for dinner such as a chilli.
And, just as I'd been promised, I never went hungry.
I thought: I'm eating so much, I'll never lose the weight.
But within weeks, the kilos started to drop off. By the time I walked down the aisle, I was almost 20kg lighter.
'You look absolutely beautiful,' Owain told me.
Then, two weeks after the wedding, I made a discovery. I told Owain and his face lit up.
I was pregnant again. But this time, I wasn't 130kg.
I weighed just over 100kg and felt so much healthier.
Although I was very nervous, I wasn't worried that my weight would cause another miscarriage.
Instead, I felt confident that my body would nurture this baby.
My pregnancy went smoothly. I had morning sickness, but I was just so excited that I didn't care.
At last, my waters broke and my contractions began. The pain wasn't as bad as I'd expected, so I stayed at home for a few hours.
And then, all of a sudden, I got the urge to push.
Owain called the hospital and said, 'We're not going to make it. The baby's coming now.'
Within minutes, a team of midwives had arrived and 45 minutes on, I gave birth to my beautiful baby son. We named him Taliesin.
Holding him in my arms was wonderful and it made me all the more determined to keep going with my weight loss. So, when Taliesin was six months old, I went back to the club.
Now I've managed to lose another 20kg and I weigh just over 80kg. I feel like a completely different woman.
I've got so much more energy.
I feel so lucky that I've been given a second chance to be a mum.
When I lost my baby, it was a wake-up call. I needed to lose weight or else I risked losing another little life.
I've just found out I'm pregnant again, and can't wait for Taliesin to have a little brother or sister to grow up with.
Losing all that weight has meant that I can be the mum I've always wanted to be.