Basic Concepts of Menstruation

Understanding Menstruation

Menstruation is the periodic bleeding of the uterus that begins approximately 14 days after ovulation (Bobak, 2004)

Menstruation is the periodic vaginal bleeding due to the release of the endometrial lining of the uterus. Normal menstrual function is the result of interaction between the hypothalamus, pituitary, and ovary with associated changes in the target tissue in normal reproductive tract, ovary plays an important role in this process, because it seems to be responsible in regulating cyclic changes and long menstrual cycle (Greenspan , 1998).

Menstrual Cycle

1) Clinical menstruation

The majority of mid-aged women of reproductive, menstrual bleeding occurs every 25-35 days with a median cycle length is 28 days. Women with ovulatory cycles, the time interval between the beginning of menstruation to ovulation - the follicular phase - variable length. Cycles observed in women who ovulate. The time interval between the beginning of menstrual bleeding - the luteal phase - relatively constant with an average of 14 ± 2 days in most women (Grenspan, 1998).

Long menstrual bleeding also varied the length generally 4 to 6 days, but between 2 and 8 days can still be considered normal. Spending menstrual blood consist of fragments kelupasan endrometrium mixed with blood that is not necessarily the number. Typically liquid blood, but when the blood flow velocity is too large, the clot with a variety of sizes very likely to be found. Ketidakbekuan regular menstrual blood is caused by an active local fibrinolytic system in the endometrium.

The average amount of blood loss in normal women during the menstrual period has been determined by several research groups, ie 25-60 ml. Normal Hb concentration of 14 g per dL and an iron content of 3.4 mg per g of hemoglobin, blood volume contains 12-29 mg of iron and depict blood loss equal to 0.4 to 1.0 mg of iron for every day of the cycle or 150 to 400 mg per year (Cunningham, 1995).

2) hormonal aspect during the menstrual cycle

Mammals, particularly humans, reproductive cycle involves various organs, the uterus, ovaries, vagina, and mammary take place within a certain time or a lack of synchronization, it is possible the arrangement, coordination, called hormones. Hormones are chemicals that are produced by the endocrine glands, which goes in the bloodstream and affect a specific organ called the target organ. Hormones associated with the menstrual cycle is;

a) The hormones produced pituitary gonadotropin:

o Luteinizing Hormone (LH)

o Follicle Stimulating Hormone (FSH)

o Prolactin releasing hormone (PRH)

b) Ovarian Steroids

The ovaries produce progestrin, androgens, and estrogens. Much of the resulting steroid is also secreted by the adrenal gland or can be formed in peripheral tissues through changes other steroid precursors; Consequently, plasma levels of these hormones may not directly reflect the steroidogenic activity of the ovary.

3) phases of the menstrual cycle

Each of the four phases of the menstrual cycle there are changes that occur in the uterus. These phases is the result of a highly coordinated cooperation between the anterior pituitary, ovaries, and uterus. The phases are:

a) menstrual phase or desquamation

This phase, regardless of the endometrium of the uterus wall, accompanied by bleeding and layers intact stratum basale only. This phase lasts for 3-4 days.

b) post-menstrual phase or phases of regeneration

This phase, healing wounds caused by the loss of the endometrium. This condition started since menstrual phase occurs and lasts for ± 4 days.

c) Phase intermenstum or proliferative phase

After the wounds healed, there will be thickening of the endometrium ± 3.5 mm. This phase lasts from day 5 to day 14 of the menstrual cycle.

Proliferative phase is divided into three stages, namely:

o early proliferative phase, occurred at day 4 to day 7. This phase can be recognized from a thin surface epithelium and the epithelial regeneration.

o Phase proliferation middle, occurred on day 8 to day 10. This phase is a transitional form, and can be recognized from the epithelial surface in the form of high piston.

o late proliferative phase, lasting between day 11 to day 14. This phase can be identified from the uneven surface and found the number of mitosis.

d) Phase premenstrual or secretory phase

This phase lasts from day 14 to 28. This phase endometrium remains roughly thick, but the shape of the gland turned into a long winding and secrete sap increasingly apparent. The interior of the endometrial cells contained glycogen and lime are needed as food for the fertilized egg.

Secretory phase is divided into two stages, namely:

o early secretory phase, this phase endometrium thinner than the previous phase due to fluid loss.

o Phase secretion further, at this phase in the endometrial glands to grow and become more winding and secretion began removing sap containing glycogen and fat. The end of this period, to turn towards endometrial stromal cells; decidua, especially those surrounding the arterial vessels. This situation facilitates the nidasi (Hanafi, 1997).

4) The mechanism of the menstrual cycle

During menstruation, the day bermulanya taken as the first day of the new cycle. There will be another increase of FSH to reach levels 5 ng / ml (equivalent to 10 MUI / ml), under the influence of both gonadotropin synergistically, these developing follicles produce estradiol in significant amounts. Increased serum constantly in the late follicular phase would suppress FSH from the pituitary. Two days before ovulation, estradiol levels reach 150-400 pg / ml. Levels exceeds the threshold value for the expenditure gonadotropin stimulation pre-ovulating. As a result, the serum FSH and LH will increase and reach a peak one day before ovulation. At the same time anyway, estradiol levels will decrease. Maximum levels of LH ranged between 8 and 35 ng / ml, equivalent to 30-40 MUI / ml, and FSH between 4-10 ng / ml, equivalent to 15-45 MUI / ml.

The occurrence of peak LH and FSH on day 14, then at this time the follicle will start to break and one day after ovulation will occur. Along with this began the formation and maturation of the corpus luteum which is accompanied by increased levels of progesterone, whereas gonadotropin began to fall back. Increased progesterone does not always make sense, that ovulation has occurred with either, because in some women who do not ovulate remains found basal body temperature and in accordance with the luteal phase endometrium.

Early luteal phase, along with the maturation of the corpus luteum. Progesterone secretion continued to increase and reached levels of between 6 and 20 ng / ml. Estradiol issued primarily from large follicles do not undergo atresia, also appears in the luteal phase with a higher concentration than during the beginning or mid-follicular phase. Production of estradiol and progesterone found maximal between days 20 and 23 (Jacoeb, 1994).
..