Why am I being asked about this?
Patients needing fertility treatment often consider that having 2 healthy babies in a twin pregnancy is the best outcome of treatment, but there are risks in a twin pregnancy and you need to be aware of them.
The overall chance of twin pregnancy remains significant if 2 embryos are replaced.
All clinics are now required by our regulators, the HFEA, to reduce this multiple pregnancy rate. We are thus giving you some information here to help you decide whether to have one or two embryos transferred.
What is the risk to the baby of being a twin?
Being a baby in a twin pregnancy is more risky.
The chance of a baby dying between 24 weeks of pregnancy and 7 days after birth (perinatal mortality rate) is:
- Singleton (one baby): 6.9 in 1000
- Twin (two babies): 27.2 in 1000
The chance of a baby having cerebral palsy is:
- Singleton (one baby): 2.3 in 1000
- Twin (two babies): 12.6 in 1000
What is the risk to the mother of a twin pregnancy?
Almost all complications of pregnancy for the mother are increased in a twin pregnancy. This includes premature delivery, problems with blood pressure, bleeding, Caesarean section and blood clots. And don’t forget that looking after twins, even if they and you are fit and well, is much more difficult.
Who should have a single embryo transfer?
Those women with the greatest risk of twins are 37 or younger and are having their first treatment. This does not mean that twins do not occur in women over 37 years but it is less likely.
We can only give you a realistic estimate of your risk of twins when we know more about your embryos. That will not be until 5 days after the eggs are collected.
What is the change in pregnancy rate if I have only one embryo transferred?
Evidence shows that if you have only one embryo transferred and you have other embryos frozen and transferred later if required, your overall chance of a baby is not reduced.
