Period
Phases of the Menstrual Cycle: meaning
Menstruation is produced by the flaking of the endometrium, the innermost lining of the uterus which has the function of welcoming and nourishing the fetus during a possible pregnancy.
In the fertile period of every woman, from menarche to menopause, the endometrium undergoes fairly regular cyclical changes, supported by changes in hormonal levels (LH, FSH, estrogen and progesterone).
In the first phase of the menstrual cycle we witness the flaking of the external endometrial surface, formed by columnar ciliated cells that overhang blood vessels, lymphatics and glands that produce mucus. Menstruation begins, with small blood losses (about 40 ml in all) mixed with mucus and cell residues. At the same time, the growth of some follicles begins in the ovary, but only one of them will be brought to complete maturation.
At the end of the menstruation, little by little the superficial circulation of the endometrium is reconstituted, which gradually increases in thickness until the moment of ovulation. At this point, the mature follicle frees the egg cell, which migrates into the fallopian tubes to be fertilized by the spermatozoa. If this magical event takes place, conception begins.
Fertilization
Menstruation and Pregnancy: How and When Can Conception Occur?
From the fusion of the genetic heritage of the spermatozoon with that of the oocyte, a cell called zygote originates, which goes against a long series of mitotic divisions, to form a cluster of cells, called blastula, in the shape of a blackberry. blastula, about a week after fertilization, to implant itself in the maternal endometrium, effectively concluding the phase of conception.
The implantation phase also lasts about seven days and is made up of three distinct events: the approach to the endometrium, the adhesion to it and the last phase of penetration (invasion)."Magically", therefore, the implant ends around the 14th day after fertilization, or the 28th day of the menstrual cycle, when in the absence of pregnancy menstruation would return.
During Pregnancy
Menstruation in Pregnancy: Is It Possible?
For what has been said, menstruation NEVER occurs during pregnancy, precisely because their appearance would signal a flaking of the endometrium and the loss of the fetus; if anything, during the initial stages of gestation the woman can experience "false menstruation", small bleeding losses with a completely different biological significance.
At the time of implantation, for example, the woman may experience a slight loss of blood, which lasts only two or three days with a limited flow but often sufficient to temporarily "hide" the state of pregnancy.
To learn more, read: Plant Losses "
Common questions
Is the absence of menstruation always synonymous with pregnancy?
The delay or non-arrival of menstruation after menarche (the woman's first menstrual flow) is not necessarily a sign of pregnancy. Strong stress, worries, strict diets, rapid weight loss, excessive physical activity, nutritional deficiencies of various kinds, gynecological infections or systemic diseases, can be accompanied by amenorrhea (disappearance of the menstrual cycle for at least three months) and oligomenorrhea (menstruation spaced by intervals longer than the canonical 28-30 days).
Is it possible to risk pregnancy by having sex during menstruation?
The chances of getting pregnant due to sexual intercourse consumed during menstruation are low, but by no means nil.
Not all menstrual cycles, in fact, have exactly the same duration and the first phase varies, the one that goes from the last menstruation to ovulation. Furthermore, spermatozoa can survive in the cervix up to 3-4 days after relationship.
How long does it take for menstruation to return after pregnancy?
During breastfeeding, ovulation continues to be suspended, as long as the lactation hormones are secreted on a regular basis, so that the newborn is exclusively breastfed, both day and night, at regular intervals and less than four hours. . Normally, menstruation will reappear only at the end of breastfeeding or, in any case, within six months of giving birth.
Unfortunately, the contraceptive efficacy of breastfeeding, although good, is not absolute, so much so that some women may experience the reappearance of menstruation already during breastfeeding; once again, however, especially in the first weeks after pregnancy, it can be simply of "false menstruation", in the specific case of the so-called lochiations, blood loss combined with pregnancy residues that occur during the puerperium.
False menstruation in pregnancy, when to worry?
There can be many reasons behind episodes of more or less intense bleeding during pregnancy. Sometimes these are serious problems, for example due to an ectopic pregnancy or placental abnormalities, other times not. For this, it is important to report any false menstruation in pregnancy to your gynecologist or attending physician.