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Development and validation of prognostic models to predict pregnancy outcomes following in-vitro fertilization (IVF) treatment

Chief investigator: David J McLernon
Research establishment: University of Aberdeen
Year of approval: 2012

Lay summary

Whilst IVF/ICSI success has conventionally been reported as the live-birth rate in a single fresh cycle, widespread use of embryo cryopreservation in the last two decades has meant that cumulative live-birth rates, which include frozen embryo replacements as well as subsequent treatment episodes, are more informative as they empower couples and clinicians to plan their care over a period of time. However, cumulative live-birth rates are often reported either as one overall average rate or stratified by female age or type of infertility at a national or IVF clinic level. Given that many other patient and treatment characteristics can affect IVF/ICSI success, it can be difficult for clinicians to counsel couples as to their individualised chances of success over a complete package of IVF/ICSI treatment. We aimed to develop (using data from 1998-2009) and temporally validate (using data from 2010-2018) three clinical prediction models to estimate the cumulative probability of treatment dependent live birth over multiple complete cycles of IVF from the following points in time: (1) At the initial consultation before IVF commences (pre-treatment); (2) After the first fresh embryo transfer attempt when treatment specific information is available (post-treatment); and (3) Before the start of a second episode of ovarian stimulation. These models were developed using the Human Fertilisation and Embryology Authority national registry database which contains fresh and frozen IVF cycle information linked to individual women from the UK. They have been converted into an online calculator called OPIS (Outcome Prediction in Subfertility) for use by clinicians and patients to calculate their individualised chance of success ( The models were temporally validated and, given that IVF practice and policy has changed much between 2010 and 2018, the models were recalibrated to predict better for new patients.

Public benefit statement

Our OPIS prediction tool helps to inform couples who are at different stages of their IVF treatment of their estimated cumulative chance of having a baby over multiple complete cycles. This helps couples to manage their expectations and to plan financially and emotionally for the number of cycles of IVF they may wish to undertake. The research also increases awareness to better understand the long journey that a couple may go through in order to achieve their wish to have a baby. The OPIS tool may also be used by those in national fertility guidance groups to facilitate policy decisions around equity of access to IVF treatment across the UK.

Scientific publications

Review date: 7 May 2026