Estradiol Level of 200 pg/mL in Fertility Treatment
An estradiol level of 200 pg/mL is within the normal range for a woman undergoing fertility treatment and generally indicates appropriate ovarian response to stimulation. 1, 2
Normal Reference Ranges
- Premenopausal women have a follicular phase estradiol range of 51-601 pg/mL, making 200 pg/mL well within normal limits 1
- Using highly accurate LC-MS/MS methodology, the early follicular phase reference interval is 31-771 pmol/L (approximately 8-210 pg/mL), and the late follicular phase extends to 104-1742 pmol/L (approximately 28-475 pg/mL) 2
- Estradiol levels below 20 pg/mL warrant investigation for functional hypothalamic amenorrhea or premature ovarian insufficiency, but 200 pg/mL is nearly 10 times this threshold 1, 3
Context in Fertility Treatment
The clinical significance depends on the specific fertility protocol and cycle timing:
- In human menopausal gonadotropin-intrauterine insemination (hMG-IUI) cycles, birth rates increase progressively with estradiol levels, rising from 3.6% when E2 <500 pg/mL to 19.6% when E2 ≥2,500 pg/mL 4
- Estradiol correlates with birth rate (r = 0.160, P <0.001) and the number of mature follicles ≥12 mm in ovarian stimulation cycles 4
- A level of 200 pg/mL suggests mild to moderate ovarian response, which may be appropriate depending on the treatment goal and protocol 4
Important Caveats
Estradiol levels must be interpreted with cycle timing and clinical context:
- Estradiol should not be interpreted in isolation without knowing cycle day and correlation with menstrual history 1
- The number of follicles ≥12 mm is more predictive of pregnancy outcomes than estradiol alone in stimulated cycles 4
- Repeat testing with FSH and LH at specific cycle days (day 3-6) may be necessary to properly assess ovarian reserve and function 1
For women on specific fertility protocols, different thresholds apply:
- Women receiving GnRH agonists with aromatase inhibitors for breast cancer should have estradiol suppressed to postmenopausal ranges (<7 pg/mL), which is a completely different clinical scenario 3
- In pubertal induction protocols for cancer survivors, estradiol levels are monitored to guide dose escalation over 24 months, with target levels varying by stage of treatment 5