-
Week 6
•The embryo has reached a size of about 8 mm (1/4 inch) in length.
•The spinal cord, which until now has been open, is beginning to close.
•The first blood cells and blood vessels are developing.
•Blood moves through these primitive vessels connected to the yolk sac.
•A pipe-shaped heart is formed and begins to beat.
•The brain begins to divide into 5 parts.
•Optic pits form the start of the developing eye.
•The cells destined to be the arms and legs are in place. -
Period: to
Fetal Development
-
Week 9
•The embryo has grown to measure 30 mm (1.2 inches) in length.
•The fingers and toes are well defined. Cartilage and bones begin to form.
•The upper lip as well as the nose tip is being formed.
•The tongue begins to develop and the larynx is developing.
•The eyelids are developed, although they stay closed for several months.
•The main construction of the heart is complete. -
Week 12
•The fetus is now about 2.5 inches (6cm) length and weighs about 0.7 ounce (20 g).
•The feet are almost half an inch (1cm) long.
•The fetus starts moving spontaneously.
•The face is beginning to look like a baby's face.
•The pancreas is functioning and producing insulin.
•Fingernails and toenails appear.
•The baby can suck his thumb, and get hiccups. -
Week 15
•Baby is now over 4 inches (10cm) long
•and weighs about 2.5 ounces (75 grams).
•He or she can move its arms and make a fist.
•Fingernails and toenails are present.
•Baby's skin is still very thin. -
Week 18
•The fetus is now 6 inches long and weighs 7 ounces.
•The fetus measures about 15cm and weighs almost 200 grams.
•They can hear sounds and may be startled by loud noises.
•Recognizable active and rest periods.
•The skin is building a protective wax layer (vernix). -
Week 23
•He or she measures over 28cm and weighs up to 550 grams.
•The baby is over 11 inches tall, weighs about a pound.
•The eyebrows are visible.
•The child can successfully suck.
•Bones located in the middle ear harden
