TV STAR Amanda Holden has given birth to a baby girl, but has spent three days in a "critical condition".
The Britain's Got Talent judge is now stable after being treated in an intensive care.
No details of Holden's condition have been released but Patrick O'Brien, a consultant obstetrician from the Royal College of Obstetricians and Gynaecologists, said bleeding during or after birth is one of the most dangerous complications patients can face.
He said there are several reasons a woman might bleed after the baby has been delivered, including tearing, the placenta becoming trapped inside, or because the uterus has not contracted after the birth and the blood vessels bleed heavily.
He said: "The risk of bleeding is related to how the baby is born. It is lowest with a successful vaginal birth, it is higher with a planned Caesarean section and highest with an emergency caesarean.
"Bleeding can be very dangerous and is the highest cause of dying in childbirth. Women can end up with blood transfusions and in rare occasions hysterectomies."
He said such complications do not affect the baby but it is possible for the placenta to separate from the womb before the birth, which can be very serious for both mother and child.
He said: "This is called an abruption and it is a problem for the mother and the baby.
"When the placenta comes away, there is less oxygen for the baby. Little abruptions are not uncommon but a big abruption can be very serious and dramatic.
"You can have a lot of bleeding, which is uncommon.
"However, people bounce back. They lose a lot of blood but it is replaced with transfusions and they get better quickly with no long-term effects."
He said such complications should not deter women from having future children.
"It is usually a one-off. However, there are underlying blood conditions a woman can have and we do a lot of tests for those."