12 weeks of gestation completes the first trimester, and now placenta takes the responsibility for maintenance of pregnancy, as it begins to produce progesterone.
Previously, this function was performed by the corpus luteum, which is now gradually fading. The risk of miscarriage is significantly reduced, and the state of woman’s health usually improves.
During 12 weeks of pregnancy the uterus increased by 10 cm. Due to this fact it cannot take place in the hip area and rises into the abdominal area, that reduces the frequency of urination. Now, however, there may appear such difficulties as heartburn and constipation, so pregnant should carefully monitor their diet and bowel movement.
Due to the increased blood volume expectant mother can detect increased heart rate and pressure. The factor of increasing the pressure can help pregnant women with low pressure and helps finally to feel better, stronger and more active.
But for those fair sex representatives, who had high pressure before pregnancy, it is necessary to monitor their condition very carefully, as the increase of pressure may cause premature detachment of the placenta and bleeding.