The length of your baby is measured in what is called Crown to Rump length, meaning the length from the top of the head, to the baby's buttock. This is considered a more accurate measurement than trying to measure head to feet length since the legs can be bent and hard to assess. Right now your baby is about 1/2 an inch long crown-to-rump, about the size of a coffee bean.

During this embryonic period your baby, called an embryo, is more highly susceptible to medications, chemicals and other toxins that can interfere with her development. Every major system, while not fully formed, has it's beginning in the embryonic stage of prenatal growth.

The previously open neural groove or tube is now closing and a rod of cells develops called a notochord. This notochord will later become the spine of your baby girl, giving her the strength to stand and walk after she is born.

Your baby's heartbeat is a steady 140-150 beats per minute, about twice as fast as her mother's. The heartbeat can even be visible, at this young age, by using ultrasound technology.

Facial features develop quickly in a young embryo and by the end of the sixth week your baby will have eyes the size of the period at the end of this sentence. The lenses, cornea and iris of her eyes are beginning to form as well.

You may have had your first prenatal visit, to confirm pregnancy, with an OB-GYN, midwife or family practice doctor. Whichever health care provider you choose, proper prenatal care can help decrease the chances of a high risk pregnancy by recognizing and addressing any potential concerns early in the pregnancy.

Did you enjoy this article? It is part of the Pregnancy - Week by Week Through the First Trimester ebook available today!

Resources:
The Pregnancy Book: Month-by-Month by Dr. Sears

Your Pregnancy Week by Week by Lesley Regan

The Complete Book of Pregnancy and Childbirth by Sheila Kitzinger