The uterine cycle begins with the menstrual phase, which is considered day one of the cycle and typically lasts about five days. This phase is characterized by the degeneration and shedding of the stratum functionalis, the functional layer of the endometrium.
When fertilization does not occur, the corpus luteum deteriorates, causing a significant drop in the levels of estrogen and progesterone in the body. This hormonal decrease triggers the release of prostaglandins, which cause the uterine...

The menstrual cycle is a recurrent sequence of changes in the uterine endometrium, specifically its functional layer, the stratum functionalis. This cycle prepares the uterus for potential pregnancy. This cycle typically spans 21–35 days, averaging 28 days, and aligns with the ovarian cycle, regulated by fluctuating levels of ovarian hormones, primarily estrogen and progesterone.
The menstrual phase occurs from days 1 to 5 and involves the shedding of the stratum functionalis, as a...

The proliferative phase typically occurs after menstruation and lasts between 6 to 13 days in a standard 28-day cycle. This phase involves the reconstruction of the endometrium, guided by estrogen produced by the developing ovarian follicle.
Notably, the stratum basale, the basal layer of the endometrium, including the basal parts of the uterine glands, remains unaffected by menstruation. Stem cells in this layer undergo mitosis, regenerating the stratum functionalis and thickening the...

Vasectomy is a surgical form of male sterilization that involves severing and sealing the vasa deferentia, preventing sperm from mixing with semen during ejaculation. Because a vasectomy does not impact the testes' ability to produce testosterone, hormone levels, libido, and sexual function generally remain unchanged. While vasectomy is highly effective in preventing pregnancy, with a success rate near 99.85%, rare cases of recanalization (spontaneous reconnection) can occur. Although...

The secretory phase of the menstrual cycle, spanning from day 14 to 28 in a typical 28-day cycle, is a period of significant physiological changes in the female reproductive system. This phase commences immediately after ovulation and is characterized by the preparation of the endometrium for potential embryo implantation.
Following ovulation, the corpus luteum, a temporary endocrine structure, produces progesterone and estrogens. These hormones stimulate the growth and coiling of endometrial...

The menstrual cycle includes a critical component known as the ovarian cycle, which undergoes two main phases each month—the follicular phase and the luteal phase. The follicular phase is variable and averaging around 14 days. Ovulation, triggered by a surge in luteinizing hormone (LH), marks the transition between the two phases. The second phase, the luteal phase, is relatively consistent, lasting approximately 14 days, and is marked by the activity of the corpus luteum. While a cycle...