Application of a method for estimating day of ovulation using urinary estrogen and progesterone metabolites

Epidemiology. 1995 Sep;6(5):547-50. doi: 10.1097/00001648-199509000-00015.


Longitudinal epidemiologic studies of menstrual and reproductive function are more informative if one can identify day of ovulation. We previously developed a method for estimating day of ovulation that is feasible for epidemiologic studies. The method relies on the relative concentrations of estrogen and progesterone metabolites in daily first-morning urine specimens and does not require creatinine adjustment. This paper describes results of applying this method to a large study with 724 menstrual cycles from 217 women. The method estimated a credible day of ovulation in 88% of cycles. Missing data accounted for most of the failures. When we excluded anovulatory cycles (1%) and cycles with missing data, the method estimated a day of ovulation in 97% of cycles. Variance in luteal phase length was small for our sample, suggesting that this method of identifying a day of ovulation introduces no more measurement error than when day of ovulation is determined by plasma luteinizing hormone (LH), the standard clinical method.

MeSH terms

  • Adult
  • Algorithms
  • Biomarkers / urine
  • Estrogens, Conjugated (USP) / urine
  • Estrone / analogs & derivatives*
  • Estrone / urine
  • Evaluation Studies as Topic
  • Female
  • Follicular Phase
  • Humans
  • Luteinizing Hormone / blood
  • Menstrual Cycle
  • Ovulation / blood
  • Ovulation / urine*
  • Ovulation Detection / methods*
  • Pregnancy
  • Pregnanediol / analogs & derivatives*
  • Pregnanediol / urine
  • Radioimmunoassay


  • Biomarkers
  • Estrogens, Conjugated (USP)
  • pregnanediol-3 alpha-glucuronide
  • estrone-3-glucuronide
  • Estrone
  • Luteinizing Hormone
  • Pregnanediol