PHYSIOLOGY OF THE FEMALE REPRODUCTIVE SYSTEM
Menstruation; It is characterized by vaginal bleeding of a physiological character that occurs at regular intervals during the woman's fertile period, from menarche to menopause. The pattern of menstrual bleeding
The coordination between GnRH secreted from the hypothalamus, secreted from the pituitary
FSH and LH, and ovarian sex steroids
and the resulting target organ in the endometrium
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It occurs due to cyclic interactions. Generally
ovulatory cycles last an average of 28 days, but regular cycles varying between 21 – 40
days can be encountered
. In perimenarchial or perimenopausal women, cycles may occur at shorter or longer anovulatory intervals, depending on the fluctuations in gonadotropin levels. determines. The follicular period's counterpart in the endometrial tissue is proliferative, and its counterpart in the luteal period is the secretory period.
The follicular or proliferative period includes the period from the first day of menstruation to ovulation.
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The luteal or secretory period occurs under the influence of progesterone. It is the period after ovulation
. Endometrial glands develop. The embryo becomes ready for implantation, the endometrial
glands fold and their secretions increase. Stromal edema occurs. A decidual reaction occurs.
While the luteal phase does not change and lasts 14 days, the follicular phase varies and can last 7 - 21
days.
Ovulation occurs in approximately 400 follicles throughout life. will occur. The mechanism by which follicles are selected for development is not fully known. The number of follicles that begin to develop
depends on the residual ovarian reserve. Rising FSH in the first five days of the follicular phase ensures the growth of 3 to 30 antral follicles. Only one of these follicles will ovulate
and the others will atrophy. FSH stimulation transforms the follicles into preantral follicles.
Androstenodione and testosterone are secreted from the theca and interstitial cells and provide a source for estrogen synthesis
. These androgens, synthesized by the theca cells, are secreted by granulosa cells. It diffuses into place
. As a result of aromatization of androgens with FSH stimulation in granulosa cells, estradiol production occurs. This joint division of labor between theca and granulosa cells in estrogen synthesis is called the "two cells, two gonadotropin theory". Both FSH and ostradiol together
increase the number of FSH receptors in the follicles. Estrogen feedback inhibits all follicles except the dominant follicle. The follicle rich in FSH receptor
gains dominance.
While circulating FSH decreases in the second half of the follicular phase, increased estrogen causes increased LH receptor formation with the synergistic effect of FSH
provides the transition. While LH secretion is inhibited by low levels of estrogen, it is stimulated only by high levels of estrogen. There are two critical features that enable this
:
• Concentrations exceeding 200 pg/ml
• Exposure to estrogen exceeding 50 hours.
Ovulation; Although it varies from cycle to cycle, ovulation generally occurs 10 - 12 hours after LH reaches its peak level. The sudden increase in LH occurs 24 - 36 hours after the estraidol peak. After LH reaches the highest level, estraidol begins to decrease.
The sudden increase in LH ensures the continuation of meiosis, luteinization of granulosa cells, and expansion of the cumulus
oophorus. Again, this increase in LH induces a continuous increase in progesterone
. With progesterone, the volume of the follicle increases rapidly. Progesterone, FSH, as well as proteolytic enzymes secreted under the influence of LH, and PG F2α cause the release of the ovum.
The luteal phase begins with the release of the oocyte. Progesterone levels rise rapidly after ovulation. Progesterone reaches its maximum level 8 days after the LH surge. The development of new follicles is inhibited locally and
centrally, as well as by the effects of estrogen and inhibin A.
If fecundation does not occur, progesterone begins to decrease after 6 to 8 days and when it decreases at the end of the cycle, menstrual bleeding begins.
EVALUATE FEMALE INFERTILITY. MESI The prerequisites for the formation and continuation of a healthy pregnancy can be listed as follows.
1. Healthy sperm production in the testicles of men
2. Ejaculation of the produced sperm into the posterior fornix within the vagina through sexual intercourse (coitus)
3. Regular ovulation in women
4. Retention of the egg released during ovulation by the tuba
5. The structure and functions of the cervical canal, uterine cavity and tubal lumens in women are normal and
are open to the passage of male gametes (spermatazoa) and female gametes (ovum)
6. Fertilization occurs in the ampulla part of the tube
7. Advancement of the fertilized egg towards the endometrial cavity
8. Presence of a healthy endometrium that responds to ovarian hormones and allows the implantation of the fertilized egg
9. Presence of uterine structure and hormonal support that will ensure the healthy continuation of the early pregnancy
10. Adequate general health oxygen for nutrition and oxygenation of the fetus and placenta.
Then, whether there is ovulation in female infertility and the path connecting the two germ cells
There is a pathology in the vagina, cervical canal, uterine cavity and tubes. It is necessary to investigate whether or not
An important issue to add to these is tubaperitoneal
pathologies. Before proceeding with the research, taking a careful anamnesis and performing a physical examination guides us on what to prioritize in the research.
OVULATIVE DISORDERS There are various pathologies under the name of ovulatory factor.
These are the development of the follicle, absence of ovulation, ovulation but insufficient luteinization
, failure to expel the oocyte even though the follicle is ruptured, maturation of the follicle even though there is no oocyte
atresia as a result of maturation disorder in the follicle
development. Ovulatory dysfunction constitutes 30 - 40% of female-related infertility.
It must be determined whether ovulation occurs in infertile patients. Tests performed for this purpose
are as follows:
• Menstrual history.
• Serum progesterone level measurement.
• Basal body temperature. Monitoring of blood.
• LH monitoring.
• Endometrial biopsy.
• Observation of ovulation by ultrasonography. Menstrual History: Women who normally ovulate
usually have regular menstruation every 21 - 35 days. The quantity and duration of menstruation are fixed. The presence of premenstrual and menstrual symptoms such as swollen breasts, tenderness, and dysmenorrhea are also signs of possible ovulation. Serum Progesterone Level
Measurement: Serum progesterone level is generally <3 ng/ml in the follicular phase. is. After ovulation
with the formation of the corpus luteum, the progesterone level from the luteinized granulosa cells
shows a significant increase approximately 12 hours before the start of the LH curve
. Increased serum progesterone level is an indirect sign of ovulation.
Progesterone measurement should be done in the midluteal period when secretion is at its peak.
To prove ovulation, the progesterone level in the midluteal phase is at least 6.5 ng/ml.,
The ideal is 10 ng/ml. or more. Due to the pulsatile release of progesterone
the average of the progesterone value taken on at least 3 separate days between the 20th and 24th days of the cycle
should be taken into account. In addition, the duration of the luteal phase, in which sufficient progesterone is secreted, is also important and should last fourteen days. Monitoring Basal Body Temperature: Another way to indicate ovulation
is possible by monitoring basal body temperature.
Basal body temperature is lower than the follicular phase, body temperature in the luteal phase after ovulation
It increases by 0.1 – 0.30C compared to the follicular phase. This biphasic pattern observed in basal body temperature in ovulatory women can be easily detected by measurements taken at the same time every morning, starting from the first day of the cycle
. The lowest level of basal body temperature is monitored one day before or on the day of ovulation. Progesterone, secreted by the corpus luteum formed after ovulation, has a thermogenic effect on the hypothalamus. Body temperature begins to rise
, progesterone concentration >5ng/ml. occurs when . The most fertile period
7 days before the midcycle peak of basal body temperature It is the first period.
LH Monitoring: Serial LH measurements can be made in blood and urine. Ovulation occurs 34 - 36 hours after the beginning of the LH curve and 10 hours after the LH peak. Approximately 10% of daily LH production is excreted in urine. LH is typically released in the morning hours and can only be measured in urine a few hours later. It is possible to determine the time of ovulation by serial LH measurements in urine taken twice a day.
Endometrial Biopsy: One of the most reliable imaging methods of ovulation is endometrial
It is a biopsy. It is taken with a Novak curette or pipette in the late luteal period. In endometrium biopsy
tissue should be taken from the anterior or posterior wall of the fundus, the sub-segment with weaker vascularization should not be preferred.
With endometrium biopsy, the changes caused by progesterone on the endometrium
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By detecting, it can be determined whether the cycle is ovulatory or not, whether the secretory changes are compatible with the cycle
and whether there is a pathology such as endometritis, neoplasia or tuberculosis.
In an anovulatory woman, the endometrium can be determined. Secretory changes are not observed, the endometrium
is detected as proliferative and even hyperplasic.
Observation of Ovulation with Ultrasonography: It is based on monitoring the events before and after the expulsion of the ovum
. First of all, the ovaries are evaluated at baseline with transvaginal ultrasonography on the third day of menstruation. In spontaneous cycles, the dominant follicle is selected on days 5 - 7 of the cycle. In the last stages of ovulatory development, the preovulatory follicle grows 2 mm per day. grows
and its diameter is 20 mm. when ovulation occurs. After ovulation, the follicle shrinks,
its edges become unclear, internal echo density increases and free fluid is observed in the cul de sac.
Peritoneal and Tubal Factors: It is seen in 30-35% of infertile couples. Anamnesis of pelvic inflammatory disease (PID), septic abortion, appendix rupture, previous tubal surgeries, operations performed due to ectopic pregnancy, disorders that may prevent tubal passage come to mind.
should bring. Peritoneal factors are usually PID, endometriosis or peritoneal factors that occur after previous surgery.
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