"Syngamy" is a term that refers to the joining of two genomes during fertilization. This occurs through the first mitotic division of the zygote, after the membranes of the pronuclei dissolve.

“Menarche” is the term that refers to the onset of menstrual bleeding in female humans. The timing of menarche is influenced by variety of factors including genetics and environmental factors. Age of menarche is typically between 12 to 15 years old.

During the follicular phase of the menstrual cycle, follicle-stimulating hormone (FSH) stimulates the development of multiple follicles. The follicles compete with each other and the most developed follicle becomes the dominant follicle. The dominant follicle will release an oocyte during ovulation.

Oocytes are released from the dominant follicle and travel down the fallopian tube. If the oocyte is not fertilized, it will disintegrate and be expelled from the body by way of menstruation.

The corpus luteum is a structure in female humans that develops from the dominant follicle after ovulation. The corpus luteum is involved in the endocrine system and it secretes progesterone to maintain the endometrial lining if the released oocyte is fertilized. If the oocyte is not fertilized, it stops secreting progesterone, causing the shedding of the endometrial lining and degeneration of the corpus luteum.

The corpus luteum develops from the dominant follicle after ovulation. It secretes progesterone to build up the endometrial lining and promote oocyte implantation. If the oocyte does not get fertilized, then the corpus luteum stops secreting progesterone. This causes the degeneration of the corpus luteum and menstruation.

The menstrual cycle is the development of the female reproductive system for potential pregnancy. The cycle can be divided into two parts—the ovarian cycle and the uterine cycle. The ovarian cycle has three phases—the follicular phase, ovulation, and the luteal phase.

Menopause is a stage when female humans stop ovulating and menstruating; therefore, they can no longer have children. Menopause typically occurs between 45 to 55 years. Common symptoms include hot flashes, vaginal dryness, and mood changes. Menopause occurs due to the end of estradiol and progesterone production by the ovaries.

Surgical menopause is a process in which a surgical procedure induces menopause. The procedures that do this are an oophorectomy (removal of the ovaries), hysterectomy (removal of the uterus), and salpingo-oophorectomy (removal of the fallopian tubes). These surgeries create a decrease in hormone levels that bring about menopausal symptoms.

During the luteal phase of the ovarian cycle during the menstrual cycle, progesterone levels can either maintain pregnancy or prepare the female human for menstruation. High FSH (follicle-stimulating hormone) and LH (luteinizing hormone) levels stimulate the formation of the corpus luteum from the follicle. The corpus luteum then secretes progesterone. In a negative feedback loop, the high levels of progesterone inhibit FSH and LH production, degrading the corpus luteum. The drop in progesterone levels leads to menstruation.