Your Baby's Development

During your last trimester, your baby continues to grow larger, and his body organs continue to mature. Your baby is completing his development for his introduction to the world. With your baby growing and getting heavier, the last three months can get a bit uncomfortable — just keep thinking about the end result!

Your Seventh Month (26 to 30 Weeks)

Your baby will really start squirming around between the twenty-seventh and thirty-second weeks. Starting with your seventh month, the baby's lungs continue to develop, but they are not yet fully mature. To practice waking up Mom and Dad at all hours of the night, the baby begins to develop patterns of waking and sleeping. The baby's hands are active, and fingernails are growing. Muscle coordination is getting much better. The baby can now suck her thumb and can even cry. By week twenty-eight, the baby's eyelids are opening. The lungs are developed enough that if the baby were born prematurely, she would have a good chance at survival but would need to stay in a neonatal intensive care unit (NICU). Babies born earlier than seven months also have a chance for a higher survival rate with specialized neonatal care. As your seventh month progresses and the baby grows larger, he experiences a harder time moving around in the uterus due to space constraints. However, he still seems to find the room to do some kicking and stretching. The baby gains more fat on his body to help control his own temperature.

Around the seventh month of your pregnancy, it is normal for your blood pressure to increase slightly. However, you should contact your doctor if you experience severe headaches, blurred vision, or severe swelling in your hands, feet, and/or ankles. These specific symptoms could signal the beginning of a condition called preeclampsia, which is pregnancy-induced hypertension, or high blood pressure.

By the end of this month, the eyebrows and eyelashes are filled in and any hair the baby has on his head is becoming thicker. The head is now proportioned to the rest of the body. The baby's hearing is fully developed, and she can respond to stimuli such as pain, light, and sounds. Toward the end of this month amniotic fluid begins to diminish. Your baby now measures about seventeen inches from head to toe and weighs about 2 to 4 pounds.

Your Eighth Month (31 to 34 Weeks)

Starting with your eighth month, the baby is becoming too big to move easily inside the uterus. It may seem that the baby is moving less. The baby is developing more fat beneath his thin layer of skin, and he's starting to practice opening his eyes. Most of his internal systems and organs are now well developed except the lungs, which are not quite yet fully matured. The baby's brain continues to develop at a rapid pace. These weeks mark a ton of growth for the baby. During the last seven weeks, the baby gains more than half his birth weight. As the baby becomes larger, he begins to run out of room and takes the fetal position by curling up. By the end of the eighth month, the baby begins to move into a head-down position, although that may not be his final position at birth. Your baby now measures around 19.8 inches from head to toe and weighs about 5 pounds.

Your Ninth Month (35 to 40 Weeks)

By nine months, your baby's lungs are almost fully developed. She still doesn't have quite enough fat under the skin to keep herself warm outside of the womb, but she is working on it. By the ninth month, the baby begins to drop lower into your abdomen, usually with the head in a downward position. The brain has been rapidly developing, and the baby's reflexes are coordinated so she can blink her eyes, turn her head, grasp firmly with her hands, and respond to stimuli. Every day, the baby is taking on a rounder shape, developing pinker skin, and losing her wrinkled appearance. The baby is beginning to get antibodies from you that will help protect her from illness.

In this last month, the growth of your baby tends to slow down, yet he is still collecting fat under his skin and, therefore, putting on more weight. The toenails have grown to the tips of the toes, as have the fingernails, which have grown to the tips of the fingers. The baby's arm and leg muscles are stronger, and he is beginning to practice breathing and working out his lungs. By the end of the ninth month, your baby will drop farther into your pelvis, hopefully with head aimed downward to the birth canal, to prepare for delivery. The drop of the baby will help you breathe a little easier. Your baby's length at birth is about eighteen to twenty inches on average, and she weighs about 7.5 pounds. Length and weight vary greatly from baby to baby.

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