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The stages of Pregnancy

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.

  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

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Stages of Pregnancy
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