Dr Nicolaides removed a tumour to save Chloe
Based at Kings College Hospital in London, Kypros routinely deals with the kind of medical problems in unborn children that other hospitals see once a year.
His remarkable work, including surgery in the womb, has earned him a reputation as a miracle worker among patients and doctors come from around the world for the chance to join his team.
A new BBC series, Life Before Birth, looks at Dr Nicolaides' pioneering role at the hospital's Harris Birthright Research Centre for Fetal Medicine.
It follows his work with expectant parents including Stacy and Steve, who have already lost three unborn babies to a rare disease and Debbie and Eddie, who fear they could have a Down's Syndrome baby.
The programme also marks the story of Roy and Vanessa, whose unborn daughter has a tumour as big as her head and John and Helen, whose child has excess fluid under its skin and around its vital organs and is not expected to survive.
Tragic losses
Parents attending Dr Nicolaides' clinic are often aware their unborn child may not live, but they also know his reputation as the world's leading pregnancy expert means it is the best chance they have.
Stacy, 38, has been told she will also lose her unborn boy unless platelets are injected into the umbilical cord and carried to his bloodstream.
It is a procedure which involves inserting a needle through the uterus and into the cord and could kill the unborn child if a mistake is made.
Nevertheless, she has decided to let Dr Nicolaides try and says she would not trust anybody else.
Stacy said: "He's been very good, he does not beat around the bush, he does not raise your hopes, he will tell you the truth.
"Whether the baby is going to survive or not, he won't muck about and try to raise your hopes - that's why I like him."
Tumour
Dr Nicolaides' direct and uncompromising approach has won the respect of many other patients, who know he demands extraordinary commitment and standards from his staff.
After a routine test for spina bifida Vanessa, 28, and Roy have been told their daughter has a tumour the size of a melon, which could kill her by putting too much pressure on her heart.
For Vanessa, who is 34 weeks into her pregnancy, it was a relief to be told the baby did not have spina bifida and that a safe, caesarean birth was possible.
She said: "It sounds a bit strange, but it was a relief in a way, because everything else was fine - the brain was fine, the legs were fine.
"Even though there was a growth there it made us feel a little bit better."
'They are my family'
Three weeks later Vanessa gave birth to baby Chloe and despite a scare before the tumour was removed she survived, to the clear delight of her parents and Kypros.
As surprising as Dr Nicolaides' joy may be in a doctor who has helped thousands of children into the world, it becomes clear that he is involved with his patients on a very personal level.
Dr Nicolaides said: "The foetal medicine unit is my life and the patients are my patients, they are my family.
"So, when I see a patient crying or I give people bad news I put my arms around them and many times I end up crying with them."