With the beginning of the second trimester (and this is 12 - 13 weeks of pregnancy), most women feel a surge of vivacity and vitality. Mood improves, irritability and tearfulness disappear.
During this period, the expectant mother develops an appetite, and only some pregnant women continue to be bothered by nausea in the morning (it will finally disappear by the 16th week).
During the 13th week of pregnancy, the placenta produces the hormone progesterone, which has a relaxing effect on smooth muscle fibers. This is necessary in order to reduce the tone of the uterus and prevent miscarriage, but the digestive organs also experience the same effect, which causes constipation.
At the end of the first trimester, at a period of 12-13 weeks of pregnancy, intensive preparation of the breast for lactation began. The number of lobules in the mammary glands increases, which is often accompanied by their engorgement and soreness, and the breasts can become 1-2 sizes larger.
As for the nervous system, from the 13th week of pregnancy, the balance of the processes of excitation and inhibition occurring in the brain is restored. And if earlier the latter prevailed (you felt drowsy, were slow, uncollected), now everything falls into place. In the second trimester, your efficiency will increase and you will easily cope with household and professional duties.