Effect of hydration on random levels of urinary pregnanediol glucuronide

Direct measurement of pregnanediol 3-glucuronide (PDG) in dried urine spots by liquid chromatography-mass spectrometry to detect ovulation

BACKGROUND

Non-invasive self-testing using an objective chemical method to detect ovulation is valuable for women planning conception, practising contraception or undergoing infertility investigations or treatment.

METHODS

Based on luteal phase secretion of progesterone (P₄) and excretion of its major metabolite, pregnanediol glucuronide (PDG), we developed a novel direct liquid chromatography-mass spectrometry (LCMS) method to measure PDG and other steroid glucuronides in urine and in dried urine spots (DUS) without deconjugation or derivatization. Urine PDG by LCMS and immunoassay (P3G) and P₄ by immunoassay with and without adjustment for creatinine were evaluated in daily first void urine samples from 10 women through a single menstrual cycle in which ovulation was confirmed by serial transvaginal ultrasound.

RESULTS

Urine PDG with and without creatinine adjustment was stable during the follicular phase with the expected striking rise in the luteal phase peaking at 5 days after ovulation. Using a single spot urine sample (100 μL) or a DUS (<20 μL urine) and an optimal threshold to distinguish pre- from post-ovulatory samples, in ROC analysis urine PDG adjusted for creatinine accurately identified ovulation in 92 % of samples was comparable with P3G immunoassay and superior to urine P₄ with or without adjustment for creatinine. Extending the analysis to two or three consecutive daily samples reduced the false negative rate from 8% to 2.6 % for two and 1.9 % for three urine samples.

CONCLUSIONS

This method holds promise as a non-invasive self-test method for women to determine by an objective chemical method their ovulatory status.

Pilot observational prospective cohort study on the use of a novel home-based urinary pregnanediol 3-glucuronide (PDG) test to confirm ovulation when used as adjunct to fertility awareness methods (FAMs) stage 1

RATIONALE

Ovulation confirmation is a fundamental component of the evaluation of infertility.

PURPOSE

To inform the design of a larger clinical trial to determine the effectiveness of a new home-based pregnanediol glucuronide (PDG) urine test to confirm ovulation when compared with the standard of serum progesterone.

METHODS

In this observational prospective cohort study (single group assignment) in an urban setting (stage 1), a convenience sample of 25 women (aged 18-42 years) collected daily first morning urine for luteinisinghormone (LH), PDG and kept a daily record of their cervical mucus for one menstrual cycle. Serum progesterone levels were measured to confirm ovulation. Sensitivity and specificity were used as the main outcome measures. Estimation of number of ultrasound (US)-monitored cycles needed for a future study was done using an exact binomial CI approach.

RESULTS

Recruitment over 3 months was achieved (n=28) primarily via natural fertility regulation social groups. With an attrition rate of 22%, specificity of the test was 100% for confirming ovulation. Sensitivity varied depending on whether a peak-fertility mucus day or a positive LH test was observed during the cycle (85%-88%). Fifty per cent of participants found the test results easy to determine. A total of 73 US-monitored cycles would be needed to offer a narrow CI between 95% and 100%.

CONCLUSION

This is first study to clinically evaluate this test when used as adjunct to the fertility awareness methods. While this pilot study was not powered to validate or test efficacy, it helped to provide information on power, recruitment and retention, acceptability of the procedures and ease of its use by the participants. Given this test had a preliminary result of 100% specificity, further research with a larger clinical trial (stage 2) is recommended to both improve this technology and incorporate additional approaches to confirm ovulation.

TRIAL REGISTRATION NUMBER

NCT03230084.

Use of urinary pregnanediol 3-glucuronide to confirm ovulation

OBJECTIVE

Urinary hormonal markers may assist in increasing the efficacy of Fertility Awareness Based Methods (FABM). This study uses urinary pregnanediol-3a-glucuronide (PDG) testing to more accurately identify the infertile phase of the menstrual cycle in the setting of FABM.

METHODS

Secondary analysis of an observational and simulation study, multicentre, European study. The study includes 107 women and tracks daily first morning urine (FMU), observed the changes in cervical mucus discharge, and ultrasonography to identify the day of ovulation over 326 menstrual cycles. The following three scenarios were tested: (A) use of the daily pregnandiol-3a-glucuronide (PDG) test alone; (B) use of the PDG test after the first positive urine luteinizing hormone (LH) kit result; (C) use of the PDG test after the disappearance of fertile type mucus. Two models were used: (1) one day of PDG positivity; or (2) waiting for three days of PDG positivity before declaring infertility.

RESULTS

After the first positivity of a LH test or the end of fertile mucus, three consecutive days of PDG testing over a threshold of 5μg/mL resulted in a 100% specificity for ovulation confirmation. They were respectively associated an identification of an average of 6.1 and 7.6 recognized infertile days.

CONCLUSIONS

The results demonstrate a clinical scenario with 100% specificity for ovulation confirmation and provide the theoretical background for a future development of a competitive lateral flow assay for the detection of PDG in the urine.

Utility and predictive value of a rapid measurement of urinary pregnanediol glucuronide by enzyme immunoassay in an infertility practice

STUDY OBJECTIVE

To assess the clinical utility of measuring urinary pregnanediol glucuronide in random samples in an infertility practice.

DESIGN

Samples of urine were collected from patients approximately 3 weeks from their last menstrual period to ascertain if ovulation had occurred. Each sample was tested for specific gravity before analyzing for pregnanediol glucuronide. Simultaneous venipuncture was performed to compare results from the urinary assay to quantitative measures of serum progesterone (P).

SETTING

All patients were randomly sampled.

PATIENTS

Three hundred ninety women undergoing pituitary down regulation with leuprolide acetate were chosen for study because they routinely initiate medication after documentation of ovulation.

OUTCOME MEASURES

The performance of the urinary pregnanediol glucuronide was evaluated as to its sensitivity, specificity, predictive value, and test efficiency compared with a serum measurement of 2.5 ng/mL and 10.0 ng/mL.

RESULTS

The performance characteristics of the pregnanediol glucuronide assay were directly related to the hydration status of the patient at the time of sample collection. Regardless of urine specific gravity, if pregnanediol glucuronide was qualitatively detected (greater than 3 micrograms/mL), serum P was greater than 2.5 ng/mL. However, in cases in which pregnanediol glucuronide was undetected (less than 3 micrograms/mL), results were only accurate when the specific gravity was greater than or equal to 1.020. When comparing urinary pregnanediol glucuronide values to serum greater than 10 ng/mL, both specificity and predictive value of a positive test decreased because of increased numbers of false-positive results.

CONCLUSIONS

The enzyme immunoassay measurement for pregnanediol glucuronide may replace the use of serum P in documenting the ovulatory status of many patients. However, all specimens must be checked for specific gravity and if less than 1.020, a serum P should be used to ensure accuracy.