Fourteen weeks after your LIMP, all of your baby’s major organs have formed and his intestines are sealed in the abdominal cavity. He now starts to grow and mature.
Your Baby’s Progress
By the eleventh week of pregnancy, your baby is recognizable as a human being, and he is now called a fetus (offspring) rather than an embryo. His head is very large compared to the rest of his body; by 14 weeks it will be about one-third of his whole length.
His eyes are completely formed, although the eyelids are still developing and remain closed. His face, too, is completely formed. His trunk has straightened out and the first bone tissue and ribs appear. The fingers and toes have nails, and some hair may have grown.
His external genital organs are now growing, and often the gender of the baby is discernible on a sonogram. Internally, his heart beats between 110 and 160 times per minute and his circulatory system continues to develop. The fetus swallows amniotic fluid and excretes it as urine. His sucking reflex is establishing itself– his lips purse, his head turns, and his forehead wrinkles.
The muscles he will use after birth for breathing and swallowing are also being exercised. In fact, by the end of this month your baby will have discovered movement. He now begins to move vigorously, though you probably won’t be able to feel his movements until the fourth month.
Blood Cell Production
While your baby will continue to rely on the placenta for nourishment, oxygen, and the clearance of waste until he is born, a system of blood cell formation that will eventually support independent life is essential. Toward the end of this month, the yolk asc becomes superfluous as its task of producing blood cells is taken over by your baby’s developing bone marrow, liver, and spleen.
His Support system
The placenta is developing very quickly, ensuring that there is a rich network of blood be vessels to provide your baby with vital nourishment. Now the layers thicken and grow until the chorion and membranes cover the entire inner surface area of the uterus. The umbilical cord is now completely mature and consists of three intertwined blood vessels encased in a fatty sheath.
The large vein carries nutrients and oxygen-rich blood to the fetus, while the two smaller arteries carry waste products and oxygen poor blood from the fetus to the placenta. The umbilical cord is coiled like a ring because the sheath is longer than the blood vessels. This allows him plenty of room to man oeuvre without the risk of damaging his lifeline.