Menstrual cycles begin at puberty and end at menopause. They correspond to all the physiological phenomena which prepare the female organism for a possible fertilization .
In general, the duration of a menstrual cycle is 28 days, but it is not always regular and may be longer or shorter. It can vary from one woman to another, and strong emotions such as travel can also play a role in the duration of the cycle.
The menstrual cycle is controlled by hormones. The rules (or menstruation) are the most visible manifestation of the cycle is the period of blood loss. By convention, the first day of the rules is the first day of the cycle.There are two phases in the menstrual cycle: the follicular phase and the luteal phase.
This is the first part of the cycle. It corresponds to the growth of a follicle (containing the oocyte) in an ovary, until ovulation.
This first phase of the menstrual cycle begins at the end of the period and lasts about 10 days, from the 4th to the 14th day. On the 14th day, it is ovulation: a follicle that matures, will produce an egg that will come out of the ovary.
At birth, each woman has about 500, 000 oocytes (or ovules) in the ovaries: most will atrophy and disappear. Only 450 will mature, and be ovulated (one per menstrual cycle).
The follicular phase is characterized by the secretion of estrogen that is produced by the ovarian follicles. This hormonal secretion gradually increases until the 12th or 13th day and then decreases.
The hormone FSH (follicle-stimulating hormone), which is a pituitary hormone (from the base of the brain), acts on the ovaries: it will stimulate the ovarian follicles to ensure their development, and so that one of them they become mature.
Ovulation will be caused by increased secretion of the FSH hormone, associated with the peak secretion of LH (Luteinizing hormone - another pituitary hormone).
During this phase and throughout the menstrual cycle, the uterine lining thickens: it increases from 0.5 mm at the end of the period to 3 mm at the time of ovulation.
What are the causes of vaginal dryness?
The causes of vaginal dryness are multiple and more or less complex according to the women.
The hormone drop due to the menstrual cycle is one of them.
Calculate your ovulation date!
Our ovulation calendar allows you to quickly and easily calculate your ovulation date and fertility period. Want to know the best time to be pregnant? Do the math in a few clicks!You want to react, to give your testimony or to ask a question? Go to our FORUMS Gynecology, Ovulation or A doctor answers you !
Read also :
> The female genitals
> The rules (menstruation)
> Our special page: Gynecology - all about women's health
> Rule disorders and their causes
Authors: Laëtitia Demma and Dr Nicolas Evrard.