Women's  Healthcare Topics is a website about pregnancy and your newborn baby.

Baby’s Development during Each Month of Pregnancy

Reviewed by James Brann, M.D.

How does my Baby Change in the First Month of Pregnancy?

Learn about your baby's growth for each month of pregnancy.
  • After conception, your baby will attach to the lining of your uterus and the placenta will start to form.

  • The arms and legs will begin to protrude.

  • Already, the brain and spinal cord develop

  • The heart will start beating by the end of this month.

  • The baby will grow half an inch and weigh less than 1 ounce.

The Second Month Brings Unbelievable Change

  • The eyes are closed and the eyelids form.

  • The inner part of the ear is starting to develop

  • Bones are becoming visible and the toes and fingers are developing.

  • The genitals will form structure.

  • At the end of this month, all of your baby's organs have started to develop.

  • The baby will grow to one inch and weigh one ounce by the end of this month.

The Rapid Growth of your Baby Continues Steadily during the Third Month

  • The teeth buds appear.

  • Although not yet functioning, all internal parts are formed.

  • The bones and muscles continue to rapidly develop.

  • The stomach and intestines begin to develop.

  • The skin has developed and is transparent.

  • The baby has rapidly grown to 3 1/2 inches and weighs more than 1 ounce now.

By the Fourth Month, you can Tell the Gender of Your Baby

  • The fingernails form.

  • Eyebrows and eyelashes appear.

  • Vernix, the waxy coating of the skin, is present.

  • . The skin loses its transparency and is wrinkled.

  • Fine hair called "lanugo", covers your baby.

  • The outer ear caught up with the inner ear now.

  • Your baby can swallow now.

  • Talk to your baby, it can hear now.

  • . The neck is extending.

  • Your baby now can produce urine.

  • The baby is huge now at almost 7 inches and weighs 5 ounces at the end of this month.

The Fifth Month, with Ultrasound, you can Watch your Baby Sucking his Hand

  • Your baby is moving everywhere now.

  • Sleep/wake cycles are now established.

  • The finger nails need to be trimmed.

  • Bile from the gallbladder begins to get ready to digest nutrients.

  • Girls now have all the eggs in their ovaries that they will ever produce.

  • Testicles are descending into their resting place in the scrotum.

  • Your baby measures 10 inches long and weighs one pound.

By the Sixth Month, you can Give your Baby a Haircut

  • The brain is continuing to mature.

  • Your baby's eyes are open.

  • You can fingerprint your baby.

  • Lungs are completely formed, but immature.

  • Your baby has reached one foot long and weighs about one and half pounds.

The Seventh Month brings with it, Stronger Kicks from your Baby

  • The baby reacts to light by opening and closing its eyes.

  • The “lanugo” hair starts to drop off the skin.

  • . Your baby can react to sound; you will want to begin singing and talking to your baby.

  • The grasping motion is functioning.

  • Your baby is 2 1/2 pounds and 14 inches long; big enough to survive if delivered.

The Eighth Month is Consumed with Fast Growth and Weight Gain

  • The bones are becoming hard.

  • The brain continues to progress.

  • The baby now can differentiate between sweet and sour as its taste buds mature.

  • You may notice flutters as your baby begins to hiccup.

  • Your baby is now 5 pounds and 18 inches long!

The Ninth Month is all about Getting Ready to be Delivered, the Head is Turned Downward for Birth

  • Lungs are mature and can function normally.

  • Skin is less wrinkled and covered with thick cheese-like substance called “vernix”.

  • Your baby's sleep patterns have been fully developed by now.

  • Your baby will weigh between 6 and 9 pounds at delivery and measures about 20 inches long.

Pregnancy A to Z