During the second trimester there are many tests you should have done to ensure that everything is going well and that your baby isn’t showing signs of certain chromosomal abnormalities. To learn more about these tests, visit our Prenatal Testing article.
Symptoms and Body Changes at 16 Weeks
The biggest change you will notice in your body at 16 weeks is the look and size of your breasts. Milk glands start production and veins become more visible as the blood flow increases.
You may be feeling an increased weight in your womb as your waistline continues to stretch and expand. Pregnancy back pains are also due to begin, as most women gain five to ten pounds at this point.
Hang in there, Mommy!
Baby’s Development
At 16 weeks old, your baby is already 4 ¾ inches long and weighs about 3.9 ounces. The facial muscles continue to develop, allowing him or her to make all kinds of different facial expressions.
It’s important you know the reason why I keep referring to your baby as “he or she.” During this week’s ultrasound the doctor will be able to distinguish whether your baby is a boy or girl. The genitals are fully developed and can be seen with ease during the sonogram.
As your baby continues to grow (he or she is the same size as the placenta at this point) you may be able to feel movement, which can first be noticed between 16 and 20 weeks. The development of visual sensitivity at this stage is also amazing.
Babies have been seen protecting their eyes from bright lights with their hands at this point. Breathing on its own, he or she is able to inhale and exhale the surrounding amniotic fluid.
Your baby also begins to build fat underneath the skin, which acts as insulation. The urinary and circulatory systems are functioning and your baby is able to pump about 25 quarts of blood daily.
Pregnancy Week 16 Tips
- During your doctor visits, it’s important to remember to talk to your healthcare provider about any questions, fears, feelings, pains, or other symptoms you are experiencing.
- It is normal at this stage to have sharp pains in your sides due to round ligament pain. Talking with your doctor can help reassure you, and it is important for your doctor to make sure that the pain is due to the round ligaments and nothing more serious.
- With the increase in breast size, you may find it necessary to look for more comfortable bras and maternity clothes.
Next is pregnancy at 17 weeks.

Photo credit: Tiffany Burke 16 weeks pregnant with twins, ultrasound

Photo credit: Kirsty Keiper 16 weeks pregnant ultrasound