Is an estrone-3-glucuronide (E1G) level of 100 on cycle day 20, 7 days past the luteinizing hormone (LH) surge, considered high in a female of reproductive age?

E1G Level of 100 on Cycle Day 20 (7 Days Post-LH Surge)

An estrone-3-glucuronide (E1G) level of 100 on cycle day 20, which is 7 days after the LH surge, is elevated and represents abnormally high estrogen activity during the mid-luteal phase.

Understanding Normal E1G Patterns

The mid-luteal phase (approximately 7 days post-ovulation) should show a secondary rise in E1G, but this rise is typically modest compared to the preovulatory peak 1, 2. In normal ovulatory cycles:

• E1G peaks just before the LH surge during the late follicular phase 2, 3
• After ovulation, E1G levels decline initially, then show a secondary modest elevation during the mid-luteal phase 1, 2
• The luteal phase E1G elevation is substantially lower than the preovulatory peak 2

Clinical Significance of Elevated E1G at This Timepoint

Your E1G level of 100 at 7 days post-LH surge is concerning for several reasons:

• Research demonstrates that raised urinary estrone-3-glucuronide excretion in the early luteal phase is associated with reproductive dysfunction, particularly in women with recurrent pregnancy loss 1
• Elevated E1G during the luteal phase may indicate inappropriate ovarian steroid hypersecretion, which can adversely affect endometrial receptivity 1
• This pattern is frequently seen alongside LH hypersecretion and elevated testosterone levels, suggesting possible polycystic ovary syndrome (PCOS) or related ovarian dysfunction 1

What This Means for Ovulation Confirmation

Despite the elevated E1G, ovulation confirmation should focus on progesterone metabolites, not estrogen metabolites 4, 5:

• Pregnanediol-3-glucuronide (PDG) is the gold standard for confirming ovulation occurred 5
• PDG should show a significant sustained rise during the mid-luteal phase (7 days post-ovulation) 5, 6
• Serum progesterone ≥5 ng/mL (or urinary PDG equivalent) confirms ovulation 4, 5

Recommended Next Steps

You should obtain concurrent PDG measurement to assess luteal function 5, 6:

• PDG levels at 7 days post-LH surge will confirm whether adequate progesterone production is occurring 5
• If PDG is appropriately elevated (confirming ovulation), the high E1G suggests luteal phase hormonal imbalance rather than anovulation 1
• Consider evaluation for polycystic ovaries and LH hypersecretion, as 81% of women with this pattern of elevated luteal estrogen have polycystic ovaries 1

Clinical Context and Pitfalls

The timing of your measurement (7 days post-LH surge) is optimal for luteal phase assessment 4, 5:

• This represents the true mid-luteal phase regardless of total cycle length 5
• However, E1G alone cannot confirm or exclude ovulation—only progesterone metabolites can 4, 5
• Normal menstrual cycles show significant individual variation in hormone patterns, with 77% differing from "textbook" mean curves 2

If you are trying to conceive or have experienced pregnancy loss, the elevated E1G warrants further investigation for underlying ovarian dysfunction, as this pattern is associated with adverse reproductive outcomes 1.