What you should know

Numbness and pregnancy – at first glance, simple processes are, in fact, very complex.

One of the prerequisites is the fertile maturity of a woman, which has a regular menstrual cycle.

Menstrual Cycle

The first menstruation is the expression of turning a girl into a woman. It is related to the maturation of hormonal regulation mechanisms (hormonal maturity – biological age) that is not parallel to the woman’s age.

The first menstrual period is usually around 13 years of age. Approximately 2.5 years from the first bleeding period, menstrual cycles may be irregular, and then stabilize at 24-35 days.

Menstrual bleeding is a manifestation of the separation of the lining-endometrium. It is the first of 4 phases of the menstrual cycle:

  • Menstruation (1-5 days) of the cycle: mucous membrane separation associated with vaginal bleeding
  • Proliferation phase (6-11 day cycle): growth and maturation of the dominant follicle and growth of the new mucous membrane in the uterus
  • Ovulation (12-14 days of the cycle): During this period (each woman individually), the egg is released from the dominant follicle and transported to the oviduct where the ovum is fertilized during unprotected contact. >
  • Secretion phase (14-28 cycle day): converting the burst follicle into a yellow body. Its role is to change the quality of the mucous membrane in the uterus so that the possible embryo is suitable for obstruction


The menstrual cycle represents cyclical changes in the ovary and mucosa in the uterine cavity.

The ovary is a “pacemaker” cycle. The amount of follicles and their degree of maturity determine the course and time sequence of the individual stages of the menstrual cycle.

During the fertile period of the female, the ovary progresses to the growth and maturation of a certain part of the follicle. Their number in the ovary is individual for each woman and is definitely determined at the beginning of puberty.


The menstrual cycle regulates the hormones formed in the hypothalamus (part of the brain) called the trigger -GnRh. Their target site is a gland stored in the human brain – a pituitary gland that starts to drain known FSH (follicle stimulating hormone responsible for follicular growth and maturation of the egg stored in it) and LH (luteinizing hormone responsible for ovulation and development and function of yellow bodies). The levels of these hormones change over the course of the cycle.

An important role in fertilization and pregnancy also plays other hormones produced by, for example, the thyroid gland, the adrenal gland, the pancreas …


Egg fertilization takes place in the eggshell. Successful fertilizations that penetrate through the mucus barrier in the neck go through the uterine cavity up to the oviduct to the egg. In order for a successful one to penetrate the egg shells into its interior, the egg must surround a larger number of quality moving sperm. Without their cooperation, fertilization is not possible.


The resulting embryo travels about 5 days through the oviduct into the uterine cavity, where about 6-7 days after fertilization is carried out – the bladder enters the mucosa that closes over it. This process is also influenced by a large number of factors.


For the physician of the assisted reproduction center (but also for your gynecologist), menstrual cycle data (length, regularity, bleeding intensity, date of last menstrual period), contraceptive use, gynecological diseases, previous pregnancy are important data. Also information about overdosed diseases, operations, medicines used in the past or actual ….

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