LH&FSH Hormones
LH Origin of production •
Luteinizing Hormone (LH) is produced in the pituitary gland under the
regulation of the Gonadotrophic releasing hormone (GnRH). • It is
then released into the blood stream towards the target tissues.
Functions of Luteinizing
• In Women • Target organs: Ovaries • Stimulate conversion of ovarian
follicle to Corpus Luteum • Acts on Corpus Luteum to stimulate
estrogen and progesterone production.
• In Men • Target organs: Testis • Predominant regulator of testicular
steroidogenesis • Acts on Leydig cells to stimulate the production of
testicular androgens.
High levels
LH in a woman’s blood can be a sign of “primary ovarian failure,” It
can happen because of • Metabolic disorder • Genetic disorder •
Autoimmune disorder or have a low number of follicles, the tiny sacs
in ovaries
• In male, abnormally high LH levels can be a sign of primary testicular
failure.
• Low levels
LH may be a sign of “secondary ovarian failure,” which means the
problem starts with the pituitary gland or hypothalamus. • Low LH
levels are linked to late puberty, and high levels are linked to early
puberty. • LH deficiency can be congenital or acquired • Causes of LH
deficiency can subdivided into hypothalamic and pituitary causes.
Function of FSH
Females • Estrogen production • Follicular development
Males • Induction and maintenance of spermatogenesis.
high FSH level in male
• Numerous studies have shown that men's serum FSH increases with
age.
Low FSH level in male
azoospermia
• Additionally, aberrant sperm morphology was the most affected
sperm parameter, and those with abnormal sperm parameters had
lower FSH levels than those with normal sperm parameters.
. High FSH level in female
Hypothalamic-pituitary dysfunction-- Infertility Gonadal dysfunction
--Estrogen deficiency-- Early menopause-- Increased ovarian follicle
growth-- Certain medications.
• Low FSH levels in women
pose a health risk, just as high FSH levels in women are concerning.
Additionally, low FSH hormone levels impair ovarian function and
render puberty development incomplete. • Infertility results from
insufficient or incomplete development of the ovarian follicles.
Hypogonadotropic hypogonadism is the medical term for low levels of
FSH in the blood.
testosterone hormones
The male gonads are the testes.
Testes have a double function: to produce and secrete the male
.hormone, testosterone, and to produce the spermatozoa
The pituitary gonadotropin LH stimulates interstitial cells in the testis
to produce testosterone and FSH promotes spermatogenesis by the
germinal cells.
Plasma testosterone levels in normal adult males range from (350 –
1200 ng/dl) and ( 30-90ng/dl ) in female.
Female sex hormones
The female gonad, ovary, has a double function; it not only produces
and secretes the female sex hormones, but it is the site of production
and maturation of the ova.
One mature ovum is released approximately once every 4 or 5
weeks. The reproductive system of female is more complicated than
in males because of the cyclical events that take place during the
menstrual cycle and even greater changes that occurs during
pregnancy.2 different chemical types of steroid hormones are
produced and secreted by ovary in non-pregnant females during
pregnancy, the same hormones are produced by the ovary, but in
different proportions. The placenta also makes the hormones that
necessary for maintenance of pregnancy.
The first group of female sex hormone, the estrogen, originate in the
ovarian follicle (and also in the placenta during pregnancy).The
estrogens participate in the menstrual cycle and are essential for the
development and maintenance of the reproductive organs and
secondary sex characteristics. The second group comprises
progesterone and its metabolites , which are formed in the corpus
luteum, the body that develops from ruptured ovarian follicle.
Progesterone is secreted after ovulation, stimulates the uterus to
undergo changes that prepare it for implantation of the fertilized
ovum and suppresses ovulation and secretion of pituitary LH. If
pregnancy occurs, the secretion of progesterone by the corpus
luteum and also by the placenta, suppresses menstruation for the
duration of the pregnancy.
Estrogens
act on several target tissues, including the uterus, vagina and breast;
progesterone mainly acts on the uterus, and is essential for the
maintenance of early pregnancy. Both estrogens and progesterone
are important in the control of the hypothalamic–pituitary–ovarian
axis. Estradiol may stimulate or inhibit the secretion of
gonadotrophins, depending on its concentration in plasma; the
stimulating effect of estradiol can be prevented by high plasma
[progesterone]. Inhibin's and activins also play a role in regulating
ovarian function and they change during the cycle; however, their
measurement is not performed as part of routine investigation.
Inhibin B originates from developing follicles
