Investigation of primary and secondary amenorrhoea, and/or gonadal failure.
Assessment of hypothalamic-pituitary function. Note that repeated sampling may be necessary in order to demonstrate impaired LH secretion because of oscillations in LH values during the day. In postmenopausal women there is less difficulty, as resting values are higher than in pre-menopausals. A pre-menopausal value in postmenopausal woman is suggestive of hypothalamic-pituitary disease. In males a low plasma testosterone with low or “normal” LH values is suggestive of hypothalamic or pituitary disease.
Detection of pre-ovulatory surge – either spontaneous or in response to clomiphene citrate. A mid-cycle LH peak precedes ovulation by 24 – 48 hours.
Polycystic ovary syndrome – some but not all of these patients (approx. 50%) may have tonically increased plasma LH levels. (FSH is normal).
Endocrinology Lab
LH
LH
Lutropin
Gonadotropins
Gonadotrophins
4 days
6547