Success rates


A good pre-implantation genetic diagnosis (PGD) service must have the back up of a successful assisted conception unit. Our results for fertility patients compare favourably with the national success rates for in vitro fertilisation (IVF), see the table below.

Success rates are published by the Human Fertilisation and Embryology Authority (HFEA). The HFEA licenses us to practice a variety of assisted conception techniques.

PGD success rates 1997-Dec 2015


 Overall (1997-2015)




No of cycles





No of embryo transfers 





Clinical pregnancies





*CPR/cycle (%)





**CPR/ET (%)





* Clinical pregnancy rate (this is defined as a pregnancy that has been confirmed to have a fetal heartbeat on scan scan not just a positive pregnancy test).

Unfortunately not all couples who start a PGD cycle end up having embryos suitable for transfer. The further a couple progresses through a cycle, the better their chance of having a baby.

We continually aim to improve our success rates through research and regular reviews of our service. We feel that it is important to be honest and realistic and we acknowledge that sadly, we will not be able to achieve a pregnancy for some couples who undergo treatment with us. Whatever the outcome, we hope that the experience will be a positive one and we will give you as much support as possible throughout your treatment.

Find out what can affect the chance of success.

Chances of having a baby following PGD

Overall, the chance of a couple having a baby born following treatment is around 40% (this is based on an average of two cycles of PGD per couple). Your chances increase if you progress successfully through each step of the treatment process. Your chances of a clinical pregnancy (pregnancy with a heartbeat seen on ultrasound scan) per cycle are:

  • one in three, when you start a cycle
  • one in two if you have embryo(s) replaced.

Babies born 1997-July 2016









Transferring an embryo

Starting a treatment cycle is no guarantee that there will be embryos suitable for transfer. Sometimes there may be no embryos to transfer for one or more of several reasons:

  • there may be very few, or no, eggs
  • some eggs may not fertilise
  • some embryos may not  grow enough to reach the testing stage
  • all embryos may be affected.

If you have a positive pregnancy test, there is still a risk that you may miscarry, or have an ectopic pregnancy (2%). Understandably, this can be disappointing and upsetting. As many couples requesting PGD are fertile, this may be one of the most difficult aspects of the treatment.


Case studies

Hear from couples who have been successfully helped by our centre.

What can affect the chances of success?

Find out what can affect the chance of success.