Progesterone ELISA

Progesterone is a C-21 steroid hormone involved in
the female menstrual cycle, pregnancy (supports
gestation) and embryogenesis of humans and other
species. Progesterone is the major naturally occurring
human progestagen.
Progesterone is important for aldosterone
(mineralocorticoid) synthesis, as 17- hydroxyprogesterone is for cortisol (glucocorticoid).
Progesterone levels are relatively low in children and
postmenopausal women. Adult males have levels
similar to those in women during the follicular phase
of the menstrual cycle.
In women, progesterone levels are relatively low
during the preovulatory phase of the menstrual cycle, rise after ovulation, and are elevated during the luteal
phase. If pregnancy occurs, progesterone levels are
maintained at luteal levels initially. After delivery of the
placenta and during lactation, progesterone levels are
very low. The fall in progesterone levels following
delivery is one of the triggers for milk production .
Progesterone is produced in the adrenal glands, the
gonads (specifically after ovulation in the corpus
luteum), the brain, and, during pregnancy, in the
placenta. Progesterone converts the endometrium to its
secretory stage to prepare the uterus for implantation.
If pregnancy does not occur, progesterone levels will
decrease, leading, in the human, to menstruation. Progesterone belongs to the group of neurosteroids
that are found in high concentrations in certain areas
in the brain and are synthesized there. Neurosteroids
affect synaptic functioning, are neuroprotective, and
affect myelinization. Progesterone has multiple effects outside of the
reproductive system. Progesterone is thermogenic, it
reduces spasm and relaxes smooth muscle. Bronchi
are widened and mucus regulated. Progesterone acts
as an antiinflammatory agent and regulates the
immune response. Progesterone also assists in
thyroid function, in bone building by osteoblasts.
Measurement of serum progesterone concentrations
have been used in evaluating ovarian function.