Your Baby's Development
By this week, some fine hairs have developed on your baby's face.
This soft colorless hair is called lanugo, and it will eventually
cover most of your baby's body until it is shed just before
delivery.
By now, your baby's genitals have fully developed, though they
may still be difficult to detect on an ultrasound examination. In
addition, your baby starts to produce thyroid hormones because the
thyroid gland has matured. Your baby now weighs about 1.6 ounces
(45 grams) and is about 3.5 inches (9 cm) long from crown to
rump.
Your Body
Under certain circumstances (for example, if you're older
than 35), your health care provider may discuss
amniocentesis
with you. Amniocentesis is a test usually done between 15 and 18
weeks that can detect abnormalities in a fetus, such as
Down syndrome
. During this test, a very thin needle is inserted into the
amniotic fluid surrounding the baby in the uterus and a sample of
the fluid is taken and analyzed. Amniocentesis does carry a very
slight risk of miscarriage, so talk to your health care provider
about your concerns and the risks and advantages of the test.
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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