FSH Levels and Hyperthyroidism Recovery
Your FSH level has likely decreased following normalization of your thyroid function, as hyperthyroidism causes reversible elevations in FSH and other reproductive hormones that return to normal with treatment. 1, 2
Hormonal Changes During Hyperthyroidism
Severe hyperthyroidism causes significant alterations in male reproductive hormones:
- FSH levels are elevated during active hyperthyroidism, though the increase is less pronounced than changes in LH 2
- LH levels increase significantly (mean 7.8 mIU/L in hyperthyroid men vs. 5.0 mIU/L in controls) with hyperresponsiveness to stimulation 2
- Total testosterone paradoxically increases (9.3 ng/mL vs. 5.4 ng/mL in controls) due to elevated sex hormone-binding globulin (SHBG), but bioavailable testosterone actually decreases (1.7 ng/mL vs. 3.1 ng/mL) 2
- Estradiol levels rise significantly (62.2 pg/mL vs. 32.1 pg/mL in controls) 2
Recovery Pattern After Treatment
The normalization of reproductive hormones follows a predictable timeline:
- FSH decreases but changes are less dramatic than other hormones during recovery 1
- LH and estradiol levels gradually decrease significantly as thyroid function normalizes 1
- SHBG levels decrease substantially, allowing free testosterone to increase and stabilize 1
- Most hormonal parameters normalize within 5 months of achieving euthyroidism 1
Semen Parameter Correlation
The improvement in semen appearance you've observed correlates with documented recovery:
- 85.7% of hyperthyroid men have asthenospermia (reduced sperm motility), which is the most common abnormality 2
- 85% of seminal alterations normalize when euthyroidism is achieved 2
- Sperm abnormalities reverse after restoration of euthyroidism, confirming that thyroid-induced reproductive changes are reversible 3, 4
Clinical Interpretation
Your FSH of 10.5 IU/L during severe hyperthyroidism was likely elevated above your baseline:
- Normal FSH in obstructive azoospermia is typically <7.6 IU/L 5
- FSH >7.6 IU/L suggests spermatogenic impairment when accompanied by testicular atrophy 5
- However, hyperthyroidism-induced FSH elevation occurs without permanent testicular damage and reverses with treatment 2, 4
Expected Outcome
Your FSH has almost certainly decreased toward normal given:
- The normalization of your semen consistency and appearance 2
- The established pattern of reproductive hormone recovery with thyroid treatment 1
- The reversible nature of hyperthyroidism-induced reproductive dysfunction 3, 4, 6
Consider repeat FSH measurement now that you're euthyroid to confirm normalization and establish your baseline reproductive hormone profile 1