How Big Is My Unborn Baby at 6 Weeks?

Most women find out they are pregnant by about four or five weeks gestation time. At six weeks along, the pregnancy still feels very new, but your baby is steadily growing and it is just a matter of time before his organs and body parts are fully developed.

Babies at Six Weeks Gestation

Babies during the sixth week of fetal development still have a lot of growing left to do and lack many distinct features. During the first month, each baby "is an embryo consisting of two layers of cells from which all her organs and body parts will develop," according to BabyCenter.

Size of Fetus at Six Weeks


What Does My Unborn Baby Look Like at 6 Weeks?

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During week six of your pregnancy, your baby will be roughly the size of a pea, and Women's Healthcare Topics says the measurements range between 2 and 5 mm. Your doctor will determine the size of your baby by taking a measurement during the ultrasound. The measurement is "referred to as 'crown-rump length' which is basically the distance from the top of your baby's head to his buttocks," according to Women's Healthcare Topics. This will seem very small, but during week four and five of fetal development, your baby only just over a millimeter long, so she is growing bit by bit.

Growth and Development of Fetus at Six Weeks

Your baby's heart should beat about 100 to 140 beats per minute, and many of your babies features are well on their way to being fully formed by week six of your pregnancy, according to Women's Healthcare Topics. The position of the nose has shifted into the right place, and dark spots are starting to form where your baby's nostrils will eventually be. Dark spots have also formed where your baby's eyes will be. Small pits on the sides of the head are visible where the ears will develop. Right now your baby's arms and legs are tiny buds, but they are continuing to grow and stretch out. Soon enough your baby will be moving on her own. Your baby's mouth, tongue, and vocal cords are starting to form. As far as internal organs, says the intestines are "located outside the baby's body within the umbilical cord" for now. Her lungs, liver, and other organs are forming.

Continuing Development of Fetus


Stages of Baby Weight in the Uterus

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As the weeks progress, features visible in week six of fetal development will become more prominent and less translucent. By week seven, your baby will measure roughly 13 mm. Her eyes are becoming more developed, and facial features are more prominent. By the end of your first trimester, you baby will be 2.2 inches long and big enough to fit in the palm of your hand.

Changes in Mother to Accomodate Fetus

By week six, you may have gained some weight. Your waist might become thicker, your uterus will begin to change size, and warns that spotting may occur in the early weeks of pregnancy, according to Women's Healthcare Topics. You may be dealing with morning sickness, and although you aren't showing yet, you might notice some of your clothes are fitting a bit tighter. Six weeks along also marks the last of the "high risk" weeks for miscarriage.