PDG Tracking for Conception: Evidence-Based Recommendation
Yes, PDG (pregnanediol-3-glucuronide) tracking is useful when trying to become pregnant, as it confirms successful ovulation and identifies luteal phase defects that may prevent conception—information that standard ovulation predictor kits miss. 1
Why PDG Tracking Matters Beyond Standard Ovulation Detection
Most couples trying to conceive rely on ovulation predictor kits that only detect the LH surge, but this tells you nothing about whether ovulation actually occurred or if the luteal phase is adequate for implantation. 1, 2 This is a critical gap because:
Confirming ovulation is essential: An LH surge doesn't guarantee that ovulation happened—PDG tracking confirms the egg was actually released by detecting the progesterone metabolite that rises only after successful ovulation. 1
Luteal phase defects are common and often missed: In one study of 40 women using complete hormone tracking, while 38 showed a PDG rise indicating ovulation occurred, only 22 maintained adequate PDG levels (>5 μg/mL) throughout the implantation window—meaning 16 women (42%) had ovulatory dysfunction that would have been completely missed by LH-only testing. 1
Timing intercourse accurately: PDG tracking combined with other hormones (E1G, LH) can identify up to 6 fertile days, with an average of 2.7 days detected before the LH surge—giving you more opportunities for conception than LH testing alone. 1
The Complete Picture: Multi-Hormone Tracking
The most effective approach combines PDG with other hormone markers rather than using PDG in isolation:
FSH for ovarian reserve assessment: Helps identify if diminished ovarian reserve may be contributing to conception difficulties. 1
E1G (estrone-3-glucuronide) for fertile window opening: Detects the estrogen rise that precedes ovulation, identifying fertile days before the LH surge. 1
LH for ovulation prediction: Identifies the surge that triggers ovulation. 1
PDG for ovulation confirmation and luteal phase adequacy: Confirms ovulation occurred (typically 2.6 days after LH surge) and assesses whether progesterone levels remain adequate for implantation. 1
Clinical Context and Practical Application
When PDG tracking becomes particularly valuable:
After 3-6 months of unsuccessful conception attempts, when you need diagnostic information beyond just timing intercourse. 3
For women over 35, where both ovarian reserve and ovulatory function may be compromised. 4
When you want to avoid unnecessary fertility workups by first confirming that ovulation is actually occurring and the luteal phase is adequate. 1, 2
How to implement PDG tracking:
Use quantitative at-home hormone monitoring systems that measure actual hormone levels (not just yes/no results) throughout your cycle. 1
Begin testing early in the follicular phase to capture the full fertile window, not just around expected ovulation. 1
Continue testing through the luteal phase to confirm sustained PDG elevation above 5 μg/mL during the implantation window (typically days 7-10 post-ovulation). 1
Important Caveats
PDG tracking is not a fertility treatment—it's a diagnostic tool that provides information. If PDG tracking reveals ovulatory dysfunction or inadequate luteal phase, you'll need medical intervention, not just better tracking. 1
Age affects cycle characteristics: Follicular phase length decreases with age while luteal phase length increases, so population-based predictions may not apply to your individual cycle without actual hormone measurement. 4
Don't rely on cycle day estimations: The standard 28-day cycle divided evenly into follicular and luteal phases is inaccurate for most women—actual hormone measurement is far more reliable than calendar-based predictions. 4
The Bottom Line
For healthy couples, approximately 85% will conceive within one year without any tracking. 5 However, PDG tracking accelerates this process by ensuring you're timing intercourse during actual fertile days and identifying ovulatory problems early—potentially saving months of unsuccessful attempts and providing actionable diagnostic information that can guide whether medical intervention is needed. 1, 2