The risk of poor ovarian response during repeat IVF

Research questionWhat are the incidence and risk factors for poor ovarian response (POR) during repeat IVF?DesignA retrospective analysis of 1224 consecutive patients who underwent at least two IVF stimulations in a single centre over a 6-year period. Risk factors from the initial treatment were assessed for association with POR during repeat IVF using logistic regression analysis. A simple, practical predictive model was constructed and evaluated for accuracy and calibration, based on the factors that demonstrated significant association with subsequent POR. POR during repeat IVF was defined as ≤3 retrieved oocytes or cancellation before retrieval following recruitment of ≤3 mature follicles.ResultsThe risk of POR during repeat IVF was approximately 11.5%. A higher POR risk during repeat IVF is associated with a reduced oocyte yield during the initial treatment (≤3 oocytes: odds ratio [OR] 14, 95% confidence interval [CI] 6.42–30.24; 4–9 oocytes: OR 4.13, 95% CI 2.00–8.54; 10–15 oocytes: OR 1) and low ovarian reserve (anti-Müllerian hormone [AMH] <5.4 pmol/l: OR 3.54, 95% CI 2.24–5.59; AMH 5.4–25 pmol/l: OR 1). Women with low ovarian reserve who experience POR during the initial IVF have the highest risk of suffering POR again during repeat IVF (57% within 1 year). Other groups, such as women with unexpected POR or expected poor responders with suboptimal ovarian response during the initial IVF, are also at risk of exhibiting POR during a subsequent treatment (28% within 1 year).ConclusionsAs there is a clear association between POR and lower live birth rates, this practical model may help manage patients’ expectations during repeat IVF treatment.