A rainbow baby is a baby born to a mother who has previously lost a child due to miscarriage, still birth or neonatal death. It stems from the idea that a rainbow, symbolising hope and comfort, follows the storm of grief caused by a baby loss.
BBC News spoke to some of the mothers who use the rainbow symbol to celebrate their children and remember the babies they lost.
'If a rainbow appears she thinks it's for her'
Cheryl Lotherington, 38, had four miscarriages before her daughter Bo (named for being a rainbow baby) was born.
She and her then partner, now husband, Grant started trying for a baby after being together for two years. She fell pregnant after six months.
"Everything seemed great," she says. "We had an early scan and saw the baby and heard the heartbeat.
"At 10 weeks I unexpectedly started bleeding. A scan confirmed that there was no heartbeat.
"The next night I miscarried at home. The pain was horrendous both physically and emotionally."
The couple, who live near Leeds, had experienced an earlier chemical pregnancy but after the first miscarriage they suffered two more losses at around 11 weeks before being referred for tests which came back clear.
"Western medicine couldn't give us any answers and my arms ached [from the injections]," she says.
They decided to get married, booked their wedding and agreed to start trying to conceive again thinking it would take about six months, but she fell pregnant straight away.
"We were scanned every week. It was a really worrying time right until she was placed in my arms."
She says her daughter, who is now four, loves colourful clothing especially anything with a rainbow on it.
"Bo tells everyone that she is a rainbow baby. If a rainbow appears she thinks it's for her. I think about the babies we have lost and how lucky we are now."
'There is always something to hope for'
Claire Todd and her husband frequently dress their two sons in rainbow clothing to celebrate them and remember the babies they lost.
Ms Todd, 37, from Sheffield, says: "My husband and I have lost seven babies in all, one for each colour of the rainbow, and have two beautiful sons.
"I love to dress them in bright colours/rainbows where possible as to me rainbows symbolise that no matter how bad things get, there is always something to hope for."
She said while they do not choose rainbow outfits all the time when they do wear bright colours they "make me smile and burst with happiness".
Pregnancy loss expressed as numbers per day*:
- 2,127 babies were born
- 10 babies were stillborn
- 684 babies were miscarried including as a result of ectopic pregnancy
- 152 babies were born preterm
*Based on 2014 UK figures from pregnancy research charity Tommy's
'We live rainbows, everywhere, everyday'
Due to fertility problems it took Nicole Lord and her husband two years to conceive their son. She had lost a pregnancy nine years ago.
She says: "We live rainbows, everywhere, everyday. But that's because they're cool as well as my son being a rainbow.
"My little man is very special to us. I don't ovulate and the usual drugs the NHS can offer don't work on me, so the fact we have a baby is remarkable."
The 25-year-old, from March, in Cambridgeshire, has a rainbow tattoo in tribute to her son.
"Even when he's big and [has] got babies of his own, I'll have this to remember the good that can come from the pain of loss."
Rainbow baby after 18 losses
Tasha Adams, from Brentford, in London, had 16 miscarriages and two stillbirths before she had her rainbow baby.
She says: "My first loss was Honey, she was stillborn in May 2007 at 36+6 [weeks], I then had seven miscarriages between June 2008 and September 2010.
"Riley Rae was stillborn at 24+3 in April 2011 and then I went on to have nine more miscarriages between June 2011 and Feb 2014."
After seven years of trying she gave birth to her son Orion Rudi Beau in June 2015.
She says: "He has the middle name Beau, because he's our Rainbow."
'She is and always will be such an important part of our family'
Frankie Brunker, from Hertfordshire, lost her daughter Esme when her heart stopped beating at just over 38 weeks in September 2013.
The 33-year-old then went on to conceive again. She says: "I was overjoyed and terrified in equal measure to get pregnant soon after our devastating loss.
"The pregnancy was problem-free like Esme's had been, but I couldn't help be filled with anxiety."
She was supported through her pregnancy by rainbow baby charity JOEL the Complete Package.
Emma Pearson, 35, from Worksop, founded the charity along with her husband Matthew after they lost their twins Noel and James in 2011.
The charity runs a Facebook group and sends support packs out with advice sections for mums, dads, grandparents and siblings.
Ms Pearson says they focus on providing support for both mums and dads. She says: "I think a lot of people ignore the fact that dads have to be that strong figure that's got to hold everything together when they've just been through something absolutely devastating.
"They're grieving exactly the same as a mum would but also they have seen their wife or partner going through labour and seeing everything that's happened is something that's really upsetting so it's important that people support them too."
Ms Brunker said the support she received helped her "stay hopeful and sane" until her son Jago was born healthy in October 2014.
She says: "We chose Jago's name partly because it means 'to follow in the footsteps of' (it's from the Hebrew name Jacob), and his middle name as Toby (the name we had picked out for Esme had she been a boy), both in tribute to his big sister.
"We don't want him to live in the shadow of Esme, but she is and always will be such an important part of our family."
'She continues to help heal our hearts every single day'
Suzanne Lowe says her daughter Ruby helped to heal her family after the loss of both her brother and her first baby.
The 33-year-old from Middleton, Manchester, lost her brother Paul in 2010 five weeks after he was diagnosed with leukaemia.
Then in 2011 she discovered she was pregnant. She says: "We were all so very happy as it had been a very hard time. I remember thinking "the light at the end of our dark tunnel"."
But a scan revealed the devastating news her son had Potter's Syndrome meaning he had very little kidney function and a poor chance of survival.
Determined to give her son a chance she continued with the pregnancy but was admitted to hospital in March 2012 when she noticed her baby's movements had decreased.
She says: "Willow-Paul Winnard Lowe was born 13:24 at 36+1 weeks. He only managed to take a breath. They worked on him but couldn't save him. Our world just crumbled.
"We got to meet this beautiful 7lb 13oz beauty that we made. He looked so perfect on the outside."
A year later Suzanne received more heartbreaking news when her mum was rushed to hospital and diagnosed with ovarian cancer, something she is still being treated for with chemotherapy.
Then in 2014 the family finally had good news when Suzanne took a pregnancy test and the result was positive.
She says: "I thought I'd be as cool as a cucumber and keep it all together when in fact I didn't.
"Our 20 week scan was a big one for us. I didn't want to know the sex like most parents do - I wanted to know that all her organs were working and could be seen. To my relief they were."
In December 2014 her daughter Ruby was born.
She says: "It felt so surreal, finally after such a long time we got to meet our rainbow baby.
"She brought so much colour back into our lives, although things are still tough going at times Ruby had helped in more ways than she will ever know.
"She continues to help heal our hearts every single day. She is so precious and so loved."