Mother:
Your heart is increasing its output to supply the baby with oxygen. Your enlarged heart is pumping about 20% more blood than prepregnancy. This volume will actually increase throughout your pregnancy for an ending increased heart output of 30-50%. If your clothes are getting tight, do not try to cram yourself into clothes try maternity clothes. The maternal blood screening for neural tube defects, often called the Alpha-fetoprotein Test (AFP) (Quad or Triple Screen) may be offered at this point. It is a screening that is most accurate during the 15 - 17th weeks of gestation.
Baby:
Your baby may have developed the habit of sucking his or her thumb! The skin is very thin and you can see the blood vessels clearly underneath.
Your baby is about 70 grams. The scalp hair pattern is developing. And the heart is pumping about 25 quarts of blood a day. This will increase to about 300 at term.
Twin Tips:
Tests like the quad screen may be altered because of a multiple pregnancy. In fact, for some women, this is how their twin pregnancy will be diagnosed. If you already knew that there was more than one, be sure that they use the appropriate scale for the measuring the test.