LH hormone and how it impacts your fertility

LH plays an important role in reproduction, puberty, fertility, and menstruation. 

• Produced in the pituitary gland, in the early part of the cycle. 
• Stimulates the ovaries to produce estradiol.
• Increases 36 hours before ovulation, giving an indication of the best time to conceive.
• Causes the ovaries to release an egg during ovulation.
• Stimulates the corpus luteum to produce progesterone to sustain pregnancy.   

Abnormal LH values can be related with:

1. LH low values – Pituitary disorder, anorexia, malnutrition, or stress.
2. LH high values – PCOS, pituitary disorder, menopause.

What is the LH hormone and how does it impact fertility?

Luteinizing hormone (LH) plays an important role in reproduction, puberty, fertility, and menstruation (Nedresky and Singh, 2019).

LH is a hormone produced and released by pituitary cells. Hypothalamus secretes a hormone called gonadotropin-realizing hormone (GnRH) that signals the pituitary gland to secrete LH and FSH (Ilahi S and Ilahi TB, 2021). LH signals ovaries to make the hormones needed to start and maintain reproductive processes. During the first weeks of the menstrual cycle, LH is required for the follicles in the ovary to begin producing estrogen, with estradiol being the predominant hormone (Nedresky and Singh, 2019). Around the 14th day of the cycle a sharp rise in LH, called LH surge, causes ovulation giving an indication of the best time to conceive (Kumar and Sait, 2011). At this time, an egg is released from a dominant follicle and the corpus luteum is formed. For the rest of the cycle, the so-called luteal phase, the LH stimulates the corpus luteum to produce the progesterone needed to support early pregnancy if fertilization occurs (Kumar and Sait, 2011). If pregnancy does not occur, the corpus luteum decomposes after about 10 days. When pregnancy occurs, LH levels are reduced and the luteal phase will be supported by another hormone, HCG (human gonadotropin) which is similar to LH but is secreted by the new placenta. During menopause, the ovaries stop working and LH levels rise (Ilahi S and Ilahi TB, 2021).

In men, LH and FSH stimulate the testicles to produce testosterone, which is essential for spermatogenesis.

How is the LH test performed? 

An LH test measures the amount of LH in a sample of blood or urine (Holesh JE, Bass AN, and Lord M. StatPearls, 2021). 

How are the LH test results interpreted in the context of fertility? 

The main clinical use of LH measurement is the evaluation of the hypothalamic-pituitary-gonadal axis (Lofrano-Porto et al. 2007).

Measurement of LH in serum is used for the following purposes:

• To assess menstrual cycle abnormalities
• To assess patients with suspected hypogonadism
• To monitor the level of LH during IVF treatment, to avoid premature ovulation
• To predict the time of ovulation in Intrauterine Insemination (IUI cases) or timed intercourse
• To assess female infertility and various pituitary lesions (very often, GH and LH are the first hormones affected in pituitary lesions

(Syed Razi H and Kazmi; Ahmet S. Can, 2021). 

Abnormal LH values can be related with:

• LH low values with the Pituitary disorder, anorexia, malnutrition, or stress.
• LH high values with PCOS, pituitary disorder, menopause

(Syed Razi H and Kazmi; Ahmet S. Can, 2021). 

What are your next steps in case of LH hormone imbalance? 

Treatment of LH imbalance depends on the underlying cause, age, and gender, as well as the desired outcome for fertility.

The estrogen is used in prepubertal girls for puberty induction and breast development.

In women who desire fertility, ovulation induction occurs with gonadotropins following estrogen therapy. For this, you must consult with your gynecologist, fertility doctor or you may also receive a consultation from Dr. Krinos Trokoudes at our clinic.