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How much variation in oocyte yield after controlled ovarian stimulation can be explained? A multilevel modelling
Oybek Rustamov1,2, Jack Wilkinson3,4, Antonio La Marca5
1Department of Reproductive Medicine, St Mary's Hospital, Central Manchester University Hospital NHS Foundation Trust, Manchester Academic Health Science Centre (MAHSC), Manchester, England M13 0JH, UK.
Human Reproduction Open
|March 22, 2019
Summary
Controlled ovarian stimulation (COS) shows significant unexplained variation in oocyte yield, even among similar women. Current patient and treatment factors explain only a small portion of this variability, limiting personalized treatment success.
Area of Science:
- Reproductive Endocrinology
- In Vitro Fertilization (IVF)
Background:
- Individualized controlled ovarian stimulation (COS) aims to optimize oocyte yield for assisted reproductive technology (ART) success.
- Personalizing treatment requires understanding and reducing variability in patient response.
Purpose of the Study:
- To quantify the variation in oocyte yield after COS.
- To determine how much of this variation can be explained by patient and treatment characteristics.
Main Methods:
- Multilevel modeling of a routine ART database (2008-2012).
- Inclusion of 1851 cycles from 1430 patients undergoing ovarian stimulation for IVF/ICSI.
- Analysis adjusted for immutable patient characteristics and modifiable treatment variables.
Main Results:
- Substantial unexplained variation in oocyte yield (3.4-fold) was observed.
- Only approximately 19% of the variation was explained by modifiable factors.
- Practitioner performing oocyte retrieval was a significant predictor of yield, with 1.5-fold variation between surgeons.
Conclusions:
- There are inherent limits to predicting and controlling COS response based on current knowledge.
- Variation in response is partly due to surgeon differences, highlighting the need for blinding in trials.
- Limited scope for personalized treatment exists without identifying new predictors of ovarian response.
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