Your Baby in the 2nd Trimester

You may start to feel more comfortable in your Second Trimester!

Month 4 of Pregnancy
Week 13

• This is the final week in your 1st Trimester!
• The fetus is now around 3 inches long!
• The intestines, which were at the base of the umbilical cord, have begun to move to the abdomen and get into their final position.
• Vocal cords are developing this week. 
• Eyes and ears are now in their permanent positions.

Week 14

• Fetuses are now all growing at different rates, but they will follow the same in-utero development. This week the fetus is somewhere around 3 1/2 inches.
• The neck is getting longer and the head is more erect, which also might have some hair on it! Right now, the fetus is covered in a thick layer of lanugo - tiny little hairs. They will disappear later.
• The fetus can now hear! 
• The lungs are fully functioning, able to "breathe" amniotic fluid in and out.

Week 15

• The fetus is now around 4 1/2 inches.
• By this point the baby is able to wiggle his/her toes and fingers and even suck a thumb.
• It has more coordination and its kicking, flexing, and moving may or may not be able to be felt by Mom!

Week 16

• Fetus is now around 4 - 5 inches and weighs somewhere around 3 - 5 ounces.
• Muscles are getting stronger, especially the back muscles, which will enable him/her to stretch out. 
• The eyes are now making movements are are able to perceive light (even though the eyelids are closed). 
• The fetus is more sensitive to touch now, as well.
• The taste buds are now mature. He/she can't taste anything yet though, because the nerve connections are still immature.

Month 5 of Pregnancy
Week 17

• The fetus is now around the size of your palm; approximately 5 inches long and around 5 - 6 ounces in weight.
• Body fat is now forming, but he/she is still quite skinny.
• Finger prints will start forming now. 

Week 18

• The fetus is now around 5 1/2 inches (around the size of a soda can).
• He/she can yawn and hiccup, which you may feel.
• He/she now has his/her own unique finger/toeprints.
• The heart now has ventricles and chambers.
• The bones in the skeleton are still very soft and pliable.

Week 19

• The fetus is now around 6 inches and around a half of a pound!
• He/she is covered in vernix.
• He/she now has a sleep and awake pattern, similar to a newborn. It also has a favorite sleep position and activity.
• Nerves are being coated with myelin. He/she now also has as many nerve cells as an adult. Connections between the muscles and the nerve cells are being established.
• If you're having a girl, her uterus is starting to develop and her vagina, fallopian tubes, and uterus are in their places. If you're having a boy, the genitals are distinct and recognizable now.
• The fetus is now swallowing amniotic fluid and making urine.

Week 20

• The fetus is now around 6 1/2 inches and approximately 10 ounces.
• He/she may startle to loud noises because he/she can now hear sounds outside of the womb. 
• The sense of taste and smell are fully developed. This means he/she can now taste what you're eating.

Month 6 of Pregnancy 
Week 21

• The fetus is now around 7 inches and almost 11 ounces. 
• He/she is no longer see through.
• Movements are much more coordinated now and the kicks are stronger because the cartilage is turning to bone.
• The fetus now has a layer of fat that will help to keep it warm after birth.

Week 22

• The fetus now weighs a pound and is around 8 inches!
• He/she can touch and pull on her umbilical cord, perceive light from darkness from outside the womb, hear your voice, as well as the voices outside of the womb, your heart beating, your circulatory system flowing, your stomach gurgling, dogs barking, loud TV's, etc.
• His/her skin is sensitive to the touch, so is you place any pressure on your abdomen, he/she will likely respond.
• Fingernails are formed and eyebrows and eyelids are full developed.

Week 23

• The fetus's lungs are starting to develop what is called "surfactant" - a greasy substance that keeps the lungs from sticking together and enables them to expand easily when the baby is born.
• The head no longer takes up half of its length - its more proportionate to a newborn, but it is still very thin and its skin is still very baggy.

Baby is now considered viable!! 
Week 24

• He/she will now start to gain around 6oz/week.
• The vital organs have developed enough to give him/her a chance at survival if born early.

Week 25

• This week he/she is 9 inches long and over 1 1/2 pounds.
• Capillaries are forming under the skin and filling with blood. By the end of the week, air sacs lined with capillaries will also develop in the lungs.
• Nostrils are starting to unplug this week, which will enable the baby to take practice breaths. You may regularly feel hiccups now.