Week 13 is the last week of the first trimester of pregnancy, or the first week of the fourth obstetric month. The main achievements of the period are the restoration of hormonal balance, the reduction of symptoms of toxicosis. The unborn child has already formed all the organs, their functioning is improving. The main tasks at this stage are the formation of an optimal diet in order to meet all the needs of a growing fetus and not gain excess weight, as well as a smooth transition to a measured life, clothing style, and new habits.
Fetal development at 13 weeks gestation
At this stage of pregnancy, the unborn child grows at a high rate. The general proportions of his body are changing just as quickly – until recently, a huge, compared to the torso, head does not increase as quickly as the torso. Soon the fetus will acquire the proportions familiar to us, inherent in small children. There is no fatty tissue yet, which will begin to grow only in the third trimester. The body of the baby is covered only by the skin, through which the blood vessels shine through.
The face of the fetus becomes more expressive, the chin and nose stand out, the eyes and ears take their place. A developed nervous system allows the child to make arbitrary movements, grimace, yawn, smile. The rudiments of all milk teeth have formed in the mouth, the vocal apparatus is actively developing, a sucking reflex has appeared.
Fetal parameters at week 13:
Weight – 15-25 g;
KTP (coccygeal-parietal size) – 8-9 cm.
If you monitor the activity of the baby, you can see that he has periods of sleep and wakefulness, and wakefulness is quite active. The movements of the fetus are no longer chaotic, it seems that they have become orderly and more accurate. Such opportunities are provided to him by a constantly improving musculoskeletal system.
At week 13, an important event occurs – the genital tubercle differentiates into the penis in boys, or into the clitoris in girls. Depending on gender, the fetus develops a prostate gland or ovaries, which occupy their intended place in the pelvic cavity. At this stage, the female fetus has the rudiments of about 2 million future eggs available. After the birth of a girl, their number will decrease.
Fetal organ development:
Villi are formed in the intestines, it occupies a permanent place in the abdominal cavity;
The diaphragm rises, lifting the respiratory organs, the esophagus;
The pancreas starts producing its own insulin responsible for glucose metabolism;
The baby’s heart works so intensively that it is able to pump more than 20 liters per day;
In place of future ribs, cartilage tissue is formed, which subsequently transforms into bone.
The child’s psyche begins its development – the first reactions to touch and pain, loud sounds, temperature changes appear. The fetus develops the ability to distinguish the taste of food, the nutrients of which enter the mother’s blood, and then through the umbilical cord to the fetus. Prenatal psychologists say that even such a tiny child feels the emotional state of the mother, feels when they communicate with him, and is even able to determine whether his mother wants him to be born, or an unwanted pregnancy.
Video about what happens to the fetus, its size, sensations, proper nutrition and much more: