What happens in the second trimester of pregnancy?
Let's find out what happens during the second trimester of pregnancy: 13 - 25 weeks
The fetuses in this trimester are already fully formed, they will concentrate their energy on weight gain, growth and maturation of their organs.
On average at 25 weeks the fetus weighs between 700 – 800 grams.
In the second trimester of pregnancy, the uterus emerges from the pelvis and the belly becomes evident. The mother is already beginning to perceive fetal movements. This is a generally calm period, without many discomforts, and in most mothers, the gastrointestinal symptoms, drowsiness, and headaches common in the first trimester disappear.
From 23 to 24 weeks of gestation, it is normal to experience some painless, irregular and short contractions of the uterus (approximately 6 to 8 a day). They do not represent an alarm sign and are intended to help position the fetus and prepare the cervix for a future birth.
Between 12 and 14 weeks, fetal sex can be determined by 70 - 95%, however, the total development of the fetal genitalia occurs between 16 and 18 weeks.
Development of the central nervous system
The primitive structures formed in the first trimester evolve during this
period to differentiate the basic structures of the nervous system
central (e.g. cerebrum, cerebellum). Also during this stage, the neurons that have
migrated become specialized (according to their genetically predetermined functionality).