Follicular phase

The follicular phase (or proliferative phase) is the phase of the estrous cycle, (or, in humans and great apes, the menstrual cycle) during which follicles in the ovary mature. It ends with ovulation. The main hormone controlling this stage is estradiol.

Follicle recruitment

Follicle-stimulating hormone (FSH) is secreted by the anterior pituitary gland. FSH secretion begins to rise in the last few days of the previous menstrual cycle, and is highest and most important during the first week of the follicular phase. The rise in FSH levels recruits five to seven tertiary-stage ovarian follicles (this stage follicle is also known as a Graafian follicle or antral follicle) for entry into the menstrual cycle. These follicles, that have been growing for the better part of a year in a process known as folliculogenesis, compete with each other for dominance.

FSH induces the proliferation of granulosa cells in the developing follicles, and the expression of luteinizing hormone (LH) receptors on these granulosa cells. Under the influence of FSH, aromatase and p450 enzymes are activated, causing the granulosa cells to begin to secrete estrogen. This increased level of estrogen stimulates production of gonadotropin-releasing hormone (GnRH), which increases production of LH. LH induces androgen synthesis by thecal cells, stimulates proliferation, differentiation, and secretion of follicular thecal cells and increases LH receptor expression on granulosa cells.

Estrogen surge

Two or three days after LH levels begin to increase, usually by day seven of the cycle, one (or occasionally two) of the recruited follicles has emerged as dominant. Many endocrinologists believe that the estrogen secretion of the dominant follicle has increased to a level that GnRH production is suppressed, which lowers the levels of LH and FSH. This slowdown in LH and FSH production leads to the atresia (death) of most of the recruited follicles, though the dominant follicle continues to mature. Estrogen levels will continue to increase for several days (on average, six days, but this varies widely).

These high estrogen levels initiate the formation of a new layer of endometrium in the uterus, histologically identified as the proliferative endometrium. Crypts in the cervix are also stimulated to produce fertile cervical mucus.This mucus reduces the acidity of the vagina, creating a more hospitable environment for sperm. It also has a characteristic texture that helps guide sperm through the cervix and to the fallopian tubes, where they wait for ovulation.In addition, basal body temperature may lower slightly under the influence of high estrogen levels.

LH surge and ovulation

Estrogen levels are highest right before the LH surge begins. The short-term drop in steroid hormones between the beginning of the LH surge and the event of ovulation may cause mid-cycle spotting or bleeding.Under the influence of the preovulatory LH surge, the first meiotic division of the oocytes is completed. The surge also initiates luteinization of thecal and granulosa cells. Ovulation normally occurs 30 (± 2) hours after the beginning of the LH surge (when LH is first detectable in urine).

Follicular waves

The time from recruitment of tertiary stage follicles to ovulation is normally about two weeks, comprising days 1-14 of an idealized 28-day menstrual cycle. However, it is common for the follicular phase to last much longer, as sometimes no dominant follicle is selected. In this case, normally more tertiary stage follicles are recruited and the process begins again. One study of women with regular menstrual cycles found that none of them ovulated after the first wave of follicle development: 68% of cycles showed ovulation after the second wave, while 32% of cycles showed ovulation after the third wave. Fertility awareness sources may refer to multiple waves of follicular development as a split peak because of the characteristic pattern of cervical mucus changes that is sometimes observed.

Tubal Ligation

Tubal ligation is a permanent form of female sterilization, in which the fallopian tubes are severed and sealed or "pinched shut", in order to prevent fertilization. Hormone production, libido, and the menstrual cycle can be affected by a tubal ligation.

A tubal ligation surgery can be done in many forms; through a vaginal approach, through laparoscopy, a minilaparotomy ("minilap"), or through regular laparotomy. Also, a distinction is made between postpartum tubal ligation and interval tubal ligation, the latter not being done after a recent delivery. There are a variety of tubal ligation techniques; the most noteworthy are the Pomeroy type that was described by Ralph Pomeroy in 1930, the Falope ring that can easily be applied via laparoscopy, and tubal cauterization done usually via laparoscopy. In addition, a bilateral salpingectomy is effective as a tubal ligation procedure. A tubal ligation can be performed as a secondary procedure when a laparotomy is done; i.e. a cesarean section. Any of these procedures may be referred to as having one's "tubes tied."

Tubal ligation can be performed under either general anesthesia or local anesthesia . The default in tubal ligations following on from cesarean birth is usually spinal/epidural, while the default in non-childbirth related situations may be general anesthesia as a matter of doctor preference. However, tubal ligations under local anesthesia, either inpatient or outpatient, may be performed under patient request.

Less commonly performed is the Essure procedure, in use since 2002. In this procedure micro-inserts are placed within the fallopian tubes by means of catheter and Hysteroscopy. The micro-inserts produce eventual occlusion of the fallopian tubes by causing the in-growth of tissue.

Immature Female Sex Cells

Immature sex cells, or oogonia, in the ovary divide by mitosis to produce oocytes. Before ovulation, one oocyte divides by meiosis to produce a secondary oocyte with half the full number of chromosomes, and a polar body. At fertilization, further divisions result in the production of the mature ovum and three superfluous polar bodies.

Reproduction

What is Ovulation

Ovulation is the process in the menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum (also known as an oocyte, female gamete, or casually, an egg) that participates in reproduction. Ovulation also occurs in the estrous cycle of other female mammals, which differs in many fundamental ways from the menstrual cycle.

The process of ovulation is controlled by the hypothalamus of the brain and through the release of hormones secreted in the anterior lobe of the pituitary gland, (Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH)). In the follicular (pre-ovulatory) phase of the menstrual cycle, the ovarian follicle will undergo a series of transformations called cumulus expansion, this is stimulated by the secretion of FSH. After this is done, a hole called the stigma will form in the follicle, and the ovum will leave the follicle through this hole. Ovulation is triggered by a spike in the amount of FSH and LH released from the pituitary gland. During the luteal (post-ovulatory) phase, the ovum will travel through the fallopian tubes toward the uterus. If fertilized by a sperm, it may perform implantation there 6-12 days later.

 


Overview

In humans, the few days near ovulation constitute the fertile phase. The average time of ovulation is the fourteenth day of an average length (twenty-eight day) menstrual cycle. It is normal for the day of ovulation to vary from the average, with ovulation anywhere between the tenth and nineteenth day being common.

Cycle length alone is not a reliable indicator of the day of ovulation. While in general an earlier ovulation will result in a shorter menstrual cycle, and vice versa, the luteal (post-ovulatory) phase of the menstrual cycle may vary by up to a week between women.

Ovulation

This is the first ever video footage of ovulation captured with an  endoscope inserted through cut in women’s vaginal wall, the patient monitored for   temperature and hormones to predict when she is about ovulate and when to begin filming, here you can see the ovary end of fallopian tubule covered by finger like projection called fimbria, A mucous plug containing the egg breaks away from the ovary, the fingers move in time with the women’s heart beat and become more distinct when the reach for the egg, eventually they sweep egg into the fallopian tube where pass into the uterus The process of ovulation is controlled by the hypothalamus of the brain and through the release of hormones secreted in the anterior lobe of the pituitary gland, (Luteinizing hormone (LH) and Follicle-stimulating hormone (FSH)). In the follicular (pre-ovulatory) phase of the menstrual cycle, the ovarian follicle will undergo a series of transformations called cumulus expansion, this is stimulated by the secretion of FSH. After this is done, a hole called the stigma will form in the follicle, and the ovum will leave the follicle through this hole. Ovulation is triggered by a spike in the amount of FSH and LH released from the pituitary gland. During the luteal (post-ovulatory) phase, the ovum will travel through the fallopian tubes toward the uterus. If fertilized by a sperm, it may perform implantation there 6-12 days later

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Ovulation is the process in the menstrual cycle by which a mature ovarian follicle ruptures and discharges an ovum (also known as an oocyte, female gamete, or casually, an egg) that participates in reproduction. Ovulation also occurs in the estrous cycle of other animals, which differs in many fundamental ways from the menstrual cycle.

In humans, the few days near ovulation constitute the fertile phase. The average time of ovulation is the fourteenth day of an average length (twenty-eight day) menstrual cycle. It is normal for the day of ovulation to vary from the average, with ovulation anywhere between the tenth and nineteenth day being common. Cycle length alone is not a reliable indicator of the day of ovulation. While in general an earlier ovulation will result in a shorter menstrual cycle, and vice versa, the luteal (post-ovulatory) phase of the menstrual cycle may vary by up to a week between women.