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Menstrual cycle review
Phases, timeline, and hormones of menstrual cycle.
This article provides a review of:
- events of the menstrual cycle, and
- timeline and hormone levels involved.
Key terms
Term | Meaning |
---|---|
menstruation | periodic shedding of endometrial lining through vagina |
menarche | first occurrence of menstruation, marking start of fertility |
menopause | ending of menstrual cycle, marking end of fertility |
ovulation | periodic release of egg from ovary |
FSH | follicle stimulating hormone |
LH | luteinizing hormone |
corpus luteum | remains of follicle that released egg |
What is the menstrual cycle?
Why do female human beings get a 'period' every month? In fact, why is it called a period? Does this happen only to humans?
All sexually mature female mammals undergo a process that allows them to reproduce. This is known as the menstrual cycle in primate mammals like humans.
Menarche, or first menstrual bleeding (first period), is considered to be the onset of puberty in human females, roughly between the ages of . Menopause is the stopping, or end of the menstrual cycle, roughly around the ages of . Reproductive ability begins and ends with these two milestones.
Menstrual cycle at a glance
The image below illustrates the timeline of the menstrual cycle, along with the hormonal changes that accompany it.
Event | Characteristics | Timeline |
---|---|---|
Menstrual phase | Shedding of endometrial lining through menstruation. | Starts on day 1, lasts up to |
Follicular/proliferative phase | Development of follicles, thickening of endometrium begins. | Follows menstrual phase, ends with ovulation. |
Ovulation | Surge in LH, rupture of Graafian follicle to release egg. | Mid cycle, roughly day |
Luteal/secretory | Maintenance of endometrium by corpus luteum. | Follows ovulation, goes on for roughly |
Want to join the conversation?
- I would like to recommend a change to the last question:
"The endometrial wall thickens as the menstrual cycle progresses, and is eventually broken down"
Correct me if I'm wrong, but the "eventually broken down" statement is referring to the menses phase. Whereas the first part of that sentence is referring to the secretory phase, which is really what they are asking. I think the question should remove the "eventually broken down" statement.(4 votes) - what happens when one have sex on the sixth day after her period?does she fall pregnant?(2 votes)
- Unlikely to get pregnant. A female’s fertile period is from the 11th to 16th day(3 votes)