When an egg leaves one of your ovaries, your body produces progesterone to help prepare the uterus for pregnancy. It's a crucial job. If your progesterone levels drop after ovulation, it can make it difficult for an embryo to make itself at home, leading to failed pregnancies. That’s why a PdG test is so important, especially for women with PCOS who are more likely to have issues conceiving.
A urine pdg test measures the amount of pregnenediol glucuronide (PdG) that you've produced in your luteal phase. It's an easy and non-invasive way to see whether you ovulated, allowing you to optimize your cycle for pregnancy.
In this study, we asked 13 women to use their Clearblue Easy Fertility Monitor with a PdG test strip during one to four menstrual cycles. The participants tracked their LH, E3G, and PdG peaks using our online charting system. They also took a urinary P4 sample using the Architect assay on day 10 of their menstrual cycle to evaluate if the P4 level in the urine was high enough to confirm ovulation.
We found that a urine P4 concentration of 5mg/mL was sufficient to confirm the LH peak in over 80% of the cycles. This is similar to the sensitivity of an ovulation test with a 7mg/mL threshold. It's also significantly better than a single threshold or percent luteal rise method which had similar sensitivity but lower positive predictive values. Our findings are encouraging for the future of PdG-based ovulation tests and suggest that it might be feasible to provide a PdG test in addition to an ovulation predictor.