Revisiting the progesterone to oocyte ratio

Fertil Steril. 2017 Mar;107(3):671-676.e2. doi: 10.1016/j.fertnstert.2016.11.019. Epub 2017 Jan 6.


Objective: To critically evaluate the P to oocyte (O) ratio (P/O) in the prediction of live birth in assisted reproductive technology (ART) cycles.

Design: Retrospective cohort study.

Setting: Not applicable.

Patient(s): A total of 7,608 fresh autologous ART ET cycles.

Intervention(s): None.

Main outcome measure(s): Live birth.

Result(s): Generalized estimating equation (GEE) models and receiver operating characteristic curves assessed the ability of P, O, and the P/O ratio to predict live birth. In univariate GEE models, P, O, and P/O were each associated with live birth. However, in multivariate GEE models, the P/O ratio was not associated with live birth, but P alone was. This suggested that converting P and O into a ratio of P/O was not more helpful than the two independent variables themselves. Measures of overall model fit further suggested that P/O did not increase the predictive ability of the model over P and O alone. Receiver operating characteristic curves using incremental predictors further demonstrated that the P/O provided no incremental improvement in predicting live birth over P and O separately.

Conclusion(s): These data suggest that P and O have utility in prediction modeling but demonstrate that additional oocytes were not protective from the negative association of P with live birth. There was no incremental improvement related to the P/O ratio specifically for predicting live birth over each variable independently.

Keywords: ART; premature progesterone elevation; progesterone; progesterone to oocyte ratio.

Publication types

  • Research Support, N.I.H., Intramural

MeSH terms

  • Adult
  • Area Under Curve
  • Biomarkers / blood
  • Female
  • Fertility / drug effects
  • Fertility Agents, Female / administration & dosage*
  • Fertility Agents, Female / adverse effects
  • Humans
  • Infertility / blood
  • Infertility / diagnosis
  • Infertility / physiopathology
  • Infertility / therapy*
  • Live Birth
  • Multivariate Analysis
  • Odds Ratio
  • Oocyte Retrieval* / adverse effects
  • Oocytes / drug effects*
  • Ovulation Induction / adverse effects
  • Ovulation Induction / methods*
  • Predictive Value of Tests
  • Pregnancy
  • Pregnancy Rate
  • Progesterone / blood*
  • ROC Curve
  • Retrospective Studies
  • Risk Factors
  • Treatment Outcome


  • Biomarkers
  • Fertility Agents, Female
  • Progesterone