Fetal Development

Fetal Development

The combining of two microscopic cells that divide and grow to form a human life in a mere 266 days is truly a miracle. Now, through modern technology, we have a window into the womb in order to chart the growth and development of a baby as he/she begins his/her life. Here are some of the milestones in the development of an unborn baby.

Conception: The sperm and egg unite to form a tiny new cell smaller than a grain of salt. The new cell contains all the genetic information for this new life–hair and eye color, size, gender, physical appearance….

Days 6-10: This new life begins to implant in the lining of the uterus.

2 Weeks: The baby is now fully attached to the uterus and drawing nourishment from the mother. A pregnancy test can provide confirmation of pregnancy.

21 Days: The heart is now beating.

4 Weeks: The baby is about an eighth of an inch long. The brain and spinal cord have formed. The eyes, arms, and legs are developing. An ultrasound can provide confirmation of pregnancy.

7 Weeks: The baby is now producing its own blood. Testicles or ovaries are starting to form.

8 Weeks: Fingers can be seen. Baby can respond to touch. Lungs begin to develop. Taste buds and eyelids begin to form.

9 Weeks: Ears and nose are visible. Bones in the arms begin to calcify. Baby is now about 3/4 of an inch long and around 1/8 of an ounce.

10 Weeks: The baby’s brain is rapidly growing and can intentionally make muscles move. Bones in legs are beginning to calcify. The outer ear is fully developed.

11 Weeks: The baby is now about 2 inches long and can yawn and suck. The eyelids are fully formed, but closed to protect the developing eyes. The kidneys begin to produce urine.

14 Weeks: The baby can now find his or her thumb and suck it. Fingernails and toenails are beginning to form. The baby can now swallow and measures about 3 1/2 inches.

16 Weeks: The gender can now be detected on ultrasound. Millions of eggs are forming in the ovaries of baby girls. The baby is about 5 inches long and weighs around 4 ounces. He/she can purposely move arms and legs, although the mother can’t feel it yet.

18 Weeks: The skeleton is hardening. Reflexes such as blinking and frowning are developing. The baby now has its own unique finger prints and can feel pain.

20 Weeks: The baby is now about 10 inches long and weighs around 11 ounces. The mother begins to feel the baby moving and is starting to “show”. The pregnancy is half over.

22 Weeks: The baby is about 11 inches long and weighs around 1 pound. Hair can be found on the head and body.

24 Weeks: Weighing close to 1.5 pounds, the baby begins to inhale amniotic fluid to prepare for breathing. The baby can hear and recognize his or her mother’s voice, breathing, and heartbeat. Rapid eye movement has already begun, an activity associated with dreaming. Some babies born at this stage will survive.

26 Weeks: Baby weighs almost 2 pounds and responds to sounds outside of the mother’s body. The eyes respond to light, eyelashes and eyebrows are apparent, and the hair on the head is growing.

28 Weeks: The baby is approximately 15 inches long and weighs close to 2.5 pounds. The brain can coordinate rhythmic breathing and regulate body temperature. The skin becomes less wrinkled.

34 Weeks: Most babies are now around 17 inches long and approximately 4.5 pounds. The eyes are wide open and respond to light.

40 Weeks: It is now time for the baby to be born. The average baby is around 20 inches long and weighs between 7 and 8 pounds.