At a little more than an inch long, the developing life is now called a fetus, which is Latin for “young one” or “offspring.” Everything is now present that will be found in a fully developed adult. The heart has been beating for more than a month, the stomach produces digestive juices and the kidneys have begun to function. Forty muscle sets begin to operate in conjunction with the nervous system. The fetus’ body responds to touch. Fingerprints are evident in the skin.
Fetal Development at 11 weeks
At this time, the fetus is about two inches long. Urination occurs. The face has assumed a baby’s profile, and muscle movements are becoming more coordinated. The fetus will curve his fingers around an object placed in his hand, can squint, swallow, and wrinkle his forehead. The fetus begins to sleep, awaken and exercise his muscles energetically – turning his head, curling his toes, and opening and closing his mouth.
Fetal Development at 15 weeks
The fetus is eight to ten inches long and weighs a half a pound or more. Fine hair is growing on his head and sexual differentiation is apparent. The ears are functioning and there is evidence that the fetus hears quite a bit: the mother’s voice and heartbeat as well as external noises. The umbilical cord has become an engineering marvel, transporting 300 quarts of fluids per day and completing a round-trip of fluids every 30 seconds.
Fetal Development at 22 weeks
The baby is more than 12 inches long by now. The mother has definitely already begun to feel movement. If a sound is especially loud or startling, the fetus may jump in reaction to it.
Fetal Development at 24 weeks
Oil and sweat glands are functioning. The delicate skin of the growing baby is protected from the fetal waters by a special ointment called “vernix.” If the baby were born now and given the proper care, he would survive.
Fetal Development at 28 weeks
The baby now uses the four senses of vision, hearing, taste, and touch. He can recognize his mother’s voice.
Fetal Development at 32 weeks
The skin begins to thicken, with a layer of fat stored underneath for insulation and nourishment. Antibodies increasingly build up. The baby absorbs a gallon of amniotic fluid per day; the fluid is completely replaced every three hours.
Fetal Development at 40 weeks
By this time, the infant normally weighs 6 to 9 pounds, and his heart is pumping about 250 gallons of blood a day. He is fully capable of life outside the womb.