By the tenth week of pregnancy, you may find yourself riding pregnancy's emotional roller coaster, feeling moody oneday and joyful the next. Disturbing as this is to some women who pride themselves on being in control, what you'regoing through is normal and will probably continue throughout your pregnancy. Up-and-down emotions are partly caused by raging hormones.
At week's end, your fetus measures approximately 1 1/2 inches long. In both shape and size, it resembles a peapod and weighs about a third of an ounce. The eyelids are fused and won't open until week 27. The wrists are more developed, ankles have formed, and the fingers and toes are clearly visible. Arms are growing longer and bend at the elbows. By week's end, the inner workings of the ears are complete. Though you can't yet identify the sex of the fetus by ultrasound, its genitals have begun to form. By now the placenta has developed enough to support most of the critical job of producing hormones.
If you're over 35 or have a family history of genetic illness, you may want to consider a chorionic villus sampling (CVS), a prenatal test usually given between ten and 12 weeks that screens for birth defects and abnormalities.