stages of pregnancy

Essay text:

The growth process of a fetus into a full-grown baby is a process that undergoes many changes that affect both the baby and the mother. Beginning: The fertilized egg is only a group of 13-32 cells after the third day the egg was implanted. It will soon change into an embryo and get 40x bigger than the size of the group of the 13-32 cells. 3 weeks: • Neural tube in the top layer of tissue, which has formed from the combination of the cells, is present in the mid-line (the area from the brain down through the spinal chord) • The brain, spinal chord, spinal nerves, and backbone will develop later from here • The heart and circulatory system are beginning to form • The first heartbeat will occur at around 21 or22 days • The foundation for bones, muscles, kidneys, and ovaries or testicles develops from the middle layer of cells • By the end of this 3rd week, the earliest blood elements and vessels have formed in the embryo and the developing placenta 4 weeks: • The embryo has tripled in size • The brain is growing and developing • The eyes and ears are beginning to form • The opening of the mouth is formed • The heart is starting to pump blood 5 weeks: • The brains development increases its complexity • Cavities for circulation of spinal fluid form • The lenses of the eyes are forming • The middle part of the ears are continuing to develop • The arms, legs, hands, and feet are taking shape 6 weeks: • The eyelids are beginning to form • The pituitory gland is developing • The arms are growing, and the wrists and elbows are evident • The fingers are beginning to form • The ears are beginning to take shape • The heart is pumping at about 150 beats per minute 7 weeks: • The embryo's tail is disappearing • The pancreas, bile ducts, and gall bladder have formed • The reproductive organs are starting to develop, but the external genitals have not yet begun to appear 8 weeks: • The beginning of all major body organs are formed • The bones of the skeleton are forming • The fingers have formed, the eyelids have grown, and outer ears are forming 9-12 weeks: • The embryo is now called a fetus, and will be called that until the time of birth • All of the organ systems are in place • The brain, nerves, and muscles are starting to function • The palate has completely formed • The genitals now have male or female characteristics 13-20 weeks: • the eyebrows and scalp hair start to appear • the skin is covered with a white, cheesy protective coating called vernix; also, lanugo (fine Hair) covers the skin • the kidneys are beginning to make urine • the vagina, uterus, and fallopian tubes have formed in the female 21-25 weeks: • the lungs are beginning to develop surfactant, which covers the inner lining of the air sacs in the lungs, allowing them to expand easily • the blood vessels in the lungs are developing to prepare for breathing, while the blood vessels in the brain are rapidly growing in the middle regions of the brain 26-29 weeks: • the eyelids can now open • the lungs are more developed, and the brain is more mature • in a male, the testicles are moving from a spot near the kidneys through the groin on their way to the scrotum • in a female, the clitoris is relatively prominent; the labia are still small and don't cover the clitoris 30-38 weeks: • In a male, the testicles have moved into the scrotum • The baby is fully developed by the last few weeks • Fluid that is present in the lungs begins to be absorbed so the baby will be prepared to breathe when he or she is born • There is a surge in fetal hormones that may aid in the maintenance of blood pressure and blood sugar levels after birth