Prenatal Development: Week 16

Now that you are 16 weeks pregnant, you could begin to notice the baby moving around inside you. And as the baby develops, these movements start to become more coordinated. Now your baby holds his head erect and with the development of his facial muscles, he can make quite a few expressions, including squinting and frowning. If you have been pregnant before, you will recognize these feelings. Those who have never experienced a pregnancy before often do not even realize that those strange 'butterfly' feelings in their tummy are actually the baby moving about.

Pregnancy Tip Help your baby develop properly by taking a prenatal vitamin that delivers more of what she needs and less of what she doesn't, like Biotegrity's Stage 2 . Specially formulated for the second trimester, these supplements have more iron, B vitamins, calcium and vitamin C as well as vitamin A so you can be sure your baby is off to a healthy start.

It's Time for a Maternal Serum Screening Test
Just about the 16th to 18th week of your pregnancy, your health care provider will probably suggest you do a maternal blood screening test. This is also known as a "triple marker" test or a "triple screen." It measures the levels of the alpha-fetoprotein (AFP), a protein produced by the fetus, the pregnancy hormones hCG as well as estriol in the mother's blood. The results from this maternal screening test alerts you if the baby is at risk for having neural tube defects such as spina bifida as well as chromosomal abnormalities, such as Down syndrome.

How Does Your Baby Look?
This week, your baby weighs around 3.53 ounces (100 grams). He measures approximately 4.6 inches (116 millimeters) in length. Around this time, his ears have shifted from near the neck to the head. Baby is emptying his bladder about every 30-45 minutes. If you had an ultrasound now, the technician would be able to determine the sex of the baby.

The baby is continuing to receive more calcium on his bones and his skeleton is still developing. If you are carrying a baby girl, millions of eggs (ova) will form in her ovaries at this time.

Select a week of development to read detailed information:

Week 1	Week 11	Week 21	Week 31
Week 2	Week 12	Week 22	Week 32
Week 3	Week 13	Week 23	Week 33
Week 4	Week 14	Week 24	Week 34
Week 5	Week 15	Week 25	Week 35
Week 6	Week 16	Week 26	Week 36
Week 7	Week 17	Week 27	Week 37
Week 8	Week 18	Week 28	Week 38
Week 9	Week 19	Week 29	Week 39
Week 10	Week 20	Week 30	Week 40

Visit the forum to talk with other women in their second trimester