OVULATION
HORMONE TESTS
To understand the hormonal events that take place during a menstrual cycle, we will review as if
we were checking the levels daily. The key hormones are FSH and LH
released by the pituitary gland, and estrogen and
progesterone released by the ovary, along with a smaller
proportion of testosterone and other male hormones. On day one of menstruation, FSH goes up and stimulates the follicle to produce estrogen.
As the follicle produces estrogen, it depresses the pituitary’s production of FSH.
Thus during the first two weeks of the cycle, as the estrogen level goes up, the FSH level goes down. The rising estrogen
begins to crescendo by day twelve and stimulates the pituitary gland to release a huge and
sudden burst of hormone LH. This sudden
burst of LH by pituitary causes ovulation. The ruptured follicle then becomes the corpus luteum and begins to manufacture progesterone
after ovulation. In the ideal 28 day cycle, this crescendo of events occurs at about day
fourteen.
During the first two weeks of the cycle, the only female hormone
produced by the ovary is estrogen. During
the second two weeks of the cycle (provide ovulation
has taken place), the ovary produces mostly progesterone and some estrogen. The addition
of progesterone converts the lining of the uterus from a
relatively thick, hard, "proliferative" surface to a more soft, spongy
"secretory" surface.
The corpus luteum normally has a life span of about
fourteen days. Only pregnancy can prolong
its function. In absence of a pregnancy,
the corpus luteum rather dramatically stops to make
hormones. When the hormones levels drop to near zero, the lining of the uterus
is shed. This is the first day of menstruation.
Because menstruation reflects a
reduction of hormone production by the ovaries to a near zero, the FSH level jumps abruptly to high levels and
the cycle begins once again.
It is impossible to say on any particular day what is
"normal’ level for any of these hormones, because the normal level varies from
day to day. Hence the BBT, the cervix and
the cervical mucus, are used as less expensive indicators of the cyclical hormonal
balance.
The initial rise of FSH
on day one is essential. Without this other events of the cycle will not occur in proper
sequence. Although ovulation is actually
triggered by a rapid rise in the circulating levels of estrogen on days twelve to
fourteen, causing the pituitary to release LH, the initial condition required for a normal cycle
is a high level of FSH during menstruation.
If hypothalamus, the primitive region of the brain, is
not functioning properly, this cyclical mechanism does not work and the woman does not ovulate. This may be one reason why stress,
anxiety, worry and lack of sleep can prevent ovulation.
It is usually impossible to determine precisely why a woman is not ovulating. The normal ovulatory function of
the menstrual system relies on a very complicated and dynamic coordination of
interrelating hormonal events. Whatever the cause of poor ovulation, the hormonal picture in almost all cases is a low FSH level at the beginning of the cycle, a
failure of the brain to respond to rising estrogen levels at mid-cycle, and too much male
hormone.
Lack of ovulation is a
true disease and is not just a problem of infertility.
The hormonal imbalance resulting from a poor ovulation
leads to buildup of a hard uterine lining that does not shed properly like the soft lining
of an ovulatory woman. This, not only leads to irregular bleeding and occasionally a painful
ovarian enlargement (which may even necessitate surgery), but over many years it can even
lead to the development of cancer
of the endometrium. Hence the problem of not getting pregnant because of poor ovulation may be far greater than simply infertility.
ULTRASONOGRAPHY
Serial Ultrasonography
studies from 14th to 18th/ 19th day are done to monitor
the growth and rupture of a follicle. Most commonly used method for ovulation profile nowadays.
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