Menstruation occurs after every 28 days, but this could vary from woman to woman. Some women experience variations that range from as short as 20 days to as long as 40 days. These irregular fluctuations are normal and are just individual differences. Irregular periods are generally experienced during puberty and menopause as these two conditions affect the menstrual cycle to a large extent. Following are the phases of menstrual cycle:
Menstruation Cycle Phases
The follicular phase lasts for about 10 to 11 days that is from the first day of periods till ovulation. This is the reason why it is known as proliferative or pre-ovulatory phase. This is the phase where Follicle Stimulating Hormone (FSH) and Luteinizing Hormone (LH) are secreted to the ovaries.
In this phase, FSH increases and egg starts maturing inside follicle. Various ovarian follicles start developing in the ovaries, but one of them becomes dominant than the others.
The wall of the uterus starts thickening in order to prepare itself for the implantation of the egg. If the egg doesn’t fertilize, the uterus lining starts getting back to its normal shape with a red blood discharge.
The ovulation phase takes place in the middle of menstrual cycle. In this phase, there is an increase in luteinizing hormone (LH) that forces the dominant follicle to release an egg or ovule. This egg can fertilize in 48 hours.
The body produces more progesterone in order to maintain the lining of the uterus. So, if you are planning for a baby, then you should know when you are ovulating in order to maximize your chances of getting pregnant. This is the phase when you will also notice an increase in your sexual desire.
In this phase, corpus luteum is formed and secretion of estrogen continues. As LH level increases, level of estrogen decreases. Corpus luteum is responsible for regulating the menstrual cycle.
When the egg doesn’t get fertilized, the progesterone and estrogen hormones are secreted continuously by corpus luteum for 14 days till it converts into corpus albicans.
If the egg fertilizes, the hormone Human Chorionic Gonadotropin (HCG) is secreted by embryo and this hormone signals the corpus luteum not to turn into corpus albicans and continue secreting progesterone and estrogen hormones.
The progesterone level increases until the end of this phase. During this phase, you may also go through pre menstrual tension which can be seen in the form of headaches, pimples, constipation, irritation, depression or mood swings.
In this phase, the uterine lining is shed in the form of menstrual flow. If the egg is not fertilized or the pregnancy doesn’t occur, then corpus luteum begins to die and it marks the beginning of your menstrual cycle. The menstruation will take place for about one week.
In case the egg gets fertilized and you become pregnant, then the corpus luteum continues to produce hormones until placenta is formed. The formation of placenta takes around 12 to 14 weeks.
During this phase, you may experience headache, nausea, diarrhea, dizziness and cramps in lower stomach, upper legs and lower backache.
The menstrual cycle causes behavioral changes in a woman as well as various other physical and internal changes. The phases defined above describe changes in fertile women.
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