The embryonic disk has become thicker and oval in shape, coiled up because the outermost layer, the ectoderm, has developed faster than the endoderm. One end of it has swollen to form the brain, and the other corresponds to the coccyx. Between the two, the neural groove will form the central nervous system.
The arm buds and then the leg buds quickly develop into limb segments and two weeks later the hands and spatula-shaped feet arise at the limb extremities. Later on, i.e. during the second half of this month, the fingers separate and acquire a tapered aspect while the limbs continue to grow longer. The knee, ankle, elbow and wrist joints also form.
In the brain, cells are multiplying and will continue to multiply until the 16th week of pregnancy, (about 3 and a half months) when several billion neurons will be produced, and at certain times, almost 250,000 per minute.
The placental membrane allows exchanges to occur more freely between mother and fetus. The fetus grows, becomes more human-looking and tends to become more independent. The placenta: a more permeable barrier.
The head, which is more prominent than the body at the beginning of the Second Month, continues to grow. The large protruding forehead takes up half of the face. The outline of the chin and neck form and separate from the trunk. The rounded protrusion of the eyes appears as a pigmented black spot, without eyelids, and connected to the brain by the optic stalk which later becomes the optic nerve. The buds for the deciduous or milk teeth form.
The fetus has become a small, vigorous being and can clench his fists and grip an object since he now possesses the grasping reflex. 7th month, the fetus who is growing and gaining weight takes up more and more room and there is less amniotic fluid. It is during these last three months of terms that the fetus grows the most; his weight triples between six and nine months of pregnancy. He now moves every day and manifests his presence so that if the mother no longer feels him move at any time during a 24 hour period, she should not hesitate to call her physician; however, the fetus may remain immobile for a few hours while sleeping.
During the 7th month, the fetus who is growing and gaining weight takes up more and more room and there is less amniotic fluid. It is during these last three months of terms that the fetus grows the most; his weight triples between six and nine months of pregnancy.
Prenatal learning and memorization of sounds may exist. Many experiments have been conducted over the last few years in an effort to determine more precisely the hearing ability of the fetus in utero. What does the fetus hear? And can the fetus remember sounds heard during intrauterine development?
During the last month of pregnancy, you should visit your physician weekly. In addition to sleep disturbances, you may experience a feeling of major lassitude and impairment due to the increasing size of the fetus. You are prepared for childbirth and you impatiently wait for the first signs of labor.