High levels of luteinizing hormone can indicate a problem with infertility as the hormone directly impacts the reproductive system. In women, LH levels that are too high are often connected to polycystic ovary syndrome, which creates inappropriate testosterone levels. Some genetic conditions, like Turner syndrome or Klinefelter syndrome, can cause high levels of the hormone.

Low levels of luteinizing hormone can also cause infertility, because insufficient levels will limit the production of sperm or the ovulation process in women. LH deficiency almost always occurs in conjunction with follicle-stimulating hormone (FSH) deficiency because LH and FSH are secreted by the same pituitary gonadotrope cells. LH deficiency can manifest in females or males as delayed puberty, hypogonadism at any age, or reproductive abnormalities that can be dramatic or subtle.