What to expect first three months of pregnancy
Filed under: baby development — Alan @ 9:33 am
In the first trimester, the embryo is developing very rapidly. For pregnant women the beginning of pregnancy is associated with huge hormonal changes, which affects about 70% of pregnant women and for some this can mean very strong, pronounced nausea.
Starting at the third week they may have increased sensitivity of the breast, usually accompanied by a feeling of tension because most spontaneous abortions (miscarriages) occur in this trimester. Most women wait until the end of the 12th week of pregnancy to make an announcement.
First Month
Pregnancy Week 1-4: fertilization and implantation
During sexual intercourse there is an insemination of sperm into the vagina. There they meet the egg. After the invasion (impregnation) there is a second meiotic division with the loss of a polar body.
The two sets of chromosomes of the egg and sperm fuse together (conjugation) and now form a viable cell (zygote), which moves within three days under hormonal control to the uterus. During this time cell divisions take place. 24 hours after fertilization begins from the cells emerges the early form of the placenta – the so-called syncytiotrophoblast – the production of the hormone hCG.
This stimulates the corpus luteum in the ovary, the secretion of another hormone, progesterone, which in turn signals to the ovaries that it is necessary for further ovulations – menstruation does not occur.
Simultaneously, these hormones for the relaxation of the uterine lining have facilitated the implantation of the blastocyst. The implantation in the uterine wall around 5 days after fertilization is completed after 14 days. Until then, twins are possible. The blastocyst is divided now into their outer layer, the trophoblast, resulting in development of the placenta, and the cell mass, from which the embryo is created. The two parts of the connective tissue becomes the umbilical cord.
Second Month
Pregnancy Week 5-8: Investment of larger institutions
This is very often associated with symptoms such as morning sickness, nausea and vomiting which are triggered by the pregnancy hormone hCG. Moreover, often there occurs, severe tiredness, food cravings and mood swings. The first amniotic fluid begins to form.
