At seven weeks, the fetus has visible facial features including a mouth and tongue. The eyes have a retina and lens and the major muscle system is developed, and the unborn child practices moving. The child has its own blood type, distinct from the mother's. Blood cells are produced by the liver now instead of the yolk sac.

At eight weeks, the unborn child, called a fetus, is  about half an inch long. This tiny person is protected  by an amniotic sac, which is filled with fluid. Inside,  the child swims and moves gracefully. The arms  and legs have lengthened and fingers can be seen.  The toes will develop in the next few days.

At ten weeks, the heart is almost completely  developed and very much resembles that of a  newborn baby. An opening at the atrium of the heart  and presence of a bypass valve divert much of the blood away from the lungs, as the child's blood is oxygenated through the placenta. 20 tiny baby teeth are forming in the gums.

Muscles lengthen and become organized. The mother will soon start feeling the first flutters of the unborn child kicking and moving within.

The fetus develops an adult's taste buds and may be able to savor the mother's meals.

By the end of this period, the fetus is five and a half inches tall and only six ouncesin weight. Eyebrows, eyelashes and fine hair are beginning to appear. The child can grasp with his hands, kick and even
somersault.

At 18 weeks' gestation (or 16 weeks since conception), the fetus can now hear.

The child can hear and recognize his/her mother's voice. Though still small and fragile, the baby is growing rapidly and could possibly survive if born at this stage. Fingernails and fingerprints appear. Sex  organs are visible. Using an ultrasound device, the doctor can tell if the child is a girl or a boy.

Seen here at six months, the unborn child is covered with a fine, downy hair called anugo. Its tender skin is protected by a waxy substance called vernix; some of this substance may be on the child's skin at birth, at which time it will be quickly absorbed. The child practices breathing by inhaling amnionic fluid into developing lungs.

For several months, the umbilical cord has been the baby's lifeline to the mother. Nourishment is transferred from the mother's blood through the placenta and into the umbilical cord to the fetus. At this stage, the child sleeps 90 to 95% of the day and sometimes experiences REM sleep, which is an indication of dreaming.

At 38 to 40 weeks, the baby is approximately 7.5 lbs and is ready for life outside its mother's womb. At birth, the placenta will detach from the side of the uterus and the umbilical cord will cease working as the child takes his first breaths of air. The child's breathing will trigger changes in the structure of the heart and bypass arteries, which will force all blood to now travel through the lungs.