The unborn child is 34 cm in length and weighs almost 690 grams.

Baby is around 13.5 inches in length and weighs 1 and half pounds.

Bones are becoming solid, hands are now fully developed.

The brain is growing rapidly, the brain cells are starting to mature.

The sexual organs are fully developed.

Baby has little body fat and its skin is thin.

The structures of the spine begin to form -- All 33 rings, 150 joints and 1000 ligaments.

The tiny brain is growing rapidly, and the baby is starting to fill the space in the uterus.

The uterus is now about the size of a soccer ball and mom looks pregnant.

Baby's hands are now fully developed.

Dexterity is improving. Your baby can make a fist and clasp objects placed in palm.

Blood vessels of the lungs develop.

Baby's nostrils begin to open.

Baby can hear sounds outside the womb and the brain cells are starting to mature also.

Already it can learn and remember and can recognize its mother and fathers voice.

Baby may hear father’s voice more easily than mother’s, as baby is sensitive to a deeper pitch.

Babies born at 25 weeks of pregnancy have about a 50% chance of survival.

The baby measures 14 inches long and weighs over 1.7 pound.

Baby measures 35.5cm long and weighs over 760 grams.

The feet are 2 inches (5cm) long. Hands are very active.

The baby's eyes begin to open around this time.

The fetus makes breathing movements, but there is no air in the lungs yet.

Hands are active and muscle coordination is such that they can get a thumb into the mouth.

Thumb sucking calms the baby and strengthens the cheek and jaw muscles.

The fetal brain scan will show response to touch.

Brain growth continues with brain wave activity for the visual and auditory systems starting to develop.

Baby is probably very active in the womb, as the most active weeks are typically between weeks 24 and 28.

A mother may begin feeling your belly tighten and relax at odd moments or irregular intervals.

These are Braxton Hicks contractions (false labour), they are painless and help the uterus prepare for the birth.

Many babies have developed a predictable routine for sleep and active periods. Twins may have entirely different routines from each other.

The end of week 26 marks the end of month six, which is the last month of the second trimester.

The fetus weighs almost 2 pounds now and is about 14.5 inches long.

Baby now weighs about 875 grams and is 36.5 cm in length.

The head is over 2.5 inches (7cm) in diameter.

Your baby's hearing continues to develop.

The eyes can blink, open and close.

This is the start of the third trimester.

Baby now has eyebrows and eyelashes and hair is growing everyday.

The muscle tone is improving and his or her body is getting plumper.

The retina at the back of your baby's eyes is beginning to develop.

If the baby is born this week, the chances of survival is now at least 80 percent. However, serious complications are still possible.

The fetus has its own regular intervals for sleeping and being awake.

The weight has increased to 1000 grams and is 37.5cm in length.

2.2 pounds weight and is 14.8 inches in length from head to heel.

The feet are just over 2 inches (5.5cm) long.

The hair on the head is now clearly visible.

The milk teeth have developed under the gums.

The eyes are starting to move in their sockets.

Brain waves show rapid eye movement (REM) sleep, which means your baby may be dreaming.

Eyelids are opening.

Eye color may change within the first six months of life especially if your baby's eyes are blue or gray-blue at birth.

He or she can recognize your voice now and will often calm to it later after birth.

Branches of lungs are quite developed now, so there is a good chance that baby would survive if born prematurely now.

If the baby is born this week, the chances of survival is now at least 90 percent. However, some complications are still possible.

Baby now weighs about 2 and a half pounds (1150gm)

About 15 inches (38.5cm) long from head to heel.

Brain is busy developing billions of neurons.

Baby's muscles and lungs are continuing to mature.

The fetus can taste and respond to pain.

The milk teeth have developed under the gums.

The baby's head is growing bigger to accommodate the brain, which is busy developing billions of neurons.

The eyes can move in their sockets. They may be able to follow a blinking light.

As well as your baby's increasing sensitivity to changes in light, they may also be able to taste.

Baby may be performing fewer movements because living conditions in the womb are becoming more cramped.

Baby measurements are 16 inches and weighs about 3 pounds.

Length is 40cm and your baby's weight is 1.4 kilograms.

The head is almost 3.5 inches (8cm) in diameter.

The feet are nearly 2.5 inches (6cm) long.

The wrinkled skin is becoming smoother now.

In boys, the testicles have moved down to the groin.

The baby controls its own body temperature.

For several months, the umbilical cord has been the baby's lifeline to the mother.

Nourishment is transferred from the mothers blood, through the placenta, and into the umbilical cord to the fetus.

Their bone marrow is now responsible for red cell production. These red blood cells will continue to service your child's body by transporting oxygen and removing the wastes.

Your baby begins storing iron, calcium and phosphorus.

Baby is getting fatter and beginning to control its own body temperature.

Baby continues to put on fat stores and the major weight gains will occur in the coming weeks.

Eyebrows and eyelashes are fully developed, and hair on the head is getting thicker.

Head and body are now proportioned like a newborn.

Hands are now fully formed and fingernails are growing.

Can be seen on ultrasound scans grasping their other hand or feet, this is helping with nerve development.

Baby weighs 3.5 pounds and measures 16.5 inches from the head to heel.

Baby's weight is about 1.6 kg and length around 42cm.

The eyes have now completely opened and are responding to light and darkness.

A loud noise near you may cause your little one to jump.

Baby's lungs and digestive tract are very near to being mature.

Now that almost all of the major organs are functioning, growth will focus on maturing those organs and growing muscle mass and fat stores.

Studies with heart rates show that they may also prefer some types of music to others at this stage.

The eyes can now completely open and the irises are now responsive to light, dilating and contracting as needed.

The baby is 17 inches (43cm) long and weighs 4 pounds (1.8 kilograms).

The diameter of the head is almost 4 inches (10cm).

Under the skin the fat layer is getting thicker.

The toenails and fingernails are completely formed.

In boys, the testicles will be descending from the groin down into his scrotum

During this time the baby sleeps most of the day.

The uterus is getting to be a small space for the baby to move about, so you may have noticed a decrease in your baby's movements.

The baby is still trying to move frequently but it just does not have enough room.

The baby will turn its head from side to side and move its hands.

If baby is a boy, his testicles are moving from their location near the kidneys through the groin on their way into the scrotum.

If your baby is a girl, her clitoris is now relatively prominent.