Estrogen Levels and Early Pregnancy Assessment
Your urinary estrone-3-glucuronide (E1G) levels of 122 µg/L on cycle days 23-24 followed by 68 µg/L on day 25 represent a substantial elevation above your baseline (6.2 µg/L) and are consistent with early pregnancy, though confirmation requires additional testing.
Understanding Your Hormone Pattern
Your E1G levels show a 20-fold increase from baseline (6.2 µg/L to 122 µg/L), which significantly exceeds the typical 5-fold increase seen during the luteal phase of non-pregnant cycles 1. This magnitude of elevation is more consistent with early pregnancy than a normal luteal phase.
Key Observations Supporting Pregnancy:
- Sustained elevation: E1G levels of 122-129 µg/L on days 21,23, and 24 represent a sustained rise well above the typical luteal phase pattern 1
- Baseline comparison: Your follicular phase E1G of 6.2 µg/L provides a clear reference point, making the 20-fold increase particularly significant 1
- Pattern consistency: Despite the drop to 68 µg/L on day 25, this level remains 11-fold higher than your baseline, which is still elevated beyond typical luteal phase values 1
Progesterone Context
Your pregnanediol-3-glucuronide (PdG) levels of 20 µg/L are artificially elevated due to progesterone supplementation, making them less useful for pregnancy assessment 2. However, the sustained PdG levels confirm adequate luteal support, which is appropriate given your supplementation 2.
Likelihood of Pregnancy
The probability of pregnancy is moderate to moderately-high based on your hormone pattern, though several factors require consideration:
Favorable Indicators:
- E1G elevation of 20-fold above baseline is substantially higher than the typical 5-fold luteal phase increase 1
- Sustained elevation across multiple days (days 21-24) 1
- Timing at 9-10 days post-ovulation is appropriate for early pregnancy hormone changes 2
Caveats:
- The drop from 122 to 68 µg/L on day 25 could represent normal day-to-day variation (which can be 25-40% even when corrected for creatinine) 1 or could signal a non-viable pregnancy
- E1G alone cannot definitively confirm pregnancy; beta-hCG testing is required for confirmation 2, 1
- Individual variation in E1G levels during early pregnancy is substantial 3
Critical Next Steps
Obtain serum beta-hCG testing immediately to confirm pregnancy status, as urinary steroid measurements alone cannot provide definitive pregnancy confirmation 1. If beta-hCG is positive, serial measurements 48 hours apart will assess pregnancy viability better than E1G monitoring 4.
Monitoring Recommendations:
- Continue progesterone supplementation as prescribed until pregnancy status is confirmed 4
- If pregnancy is confirmed, progesterone supplementation typically continues until 34-37 weeks gestation 5
- The day-to-day fluctuation in E1G (122 to 68 µg/L) is within the expected coefficient of variation and should not cause immediate alarm 1
Common Pitfall to Avoid
Do not discontinue progesterone supplementation based on E1G fluctuations alone, as progesterone support is critical during early pregnancy and should only be adjusted based on clinical assessment and beta-hCG confirmation 4, 5.