Sweat glands appear and body hair begins to grow. This is also the final week of your first trimester. Most women have their first scan this week. During an ultrasound, you may be able to notice your baby yawning and waving its arms and legs. Muscles and nervous system continue to advance. 67 of women experience nausea as a symptom during week 12 of pregnancy. Muscles function more smoothly and fetus is more flexible and has advanced movements of head, mouth and lips, arms, wrists, hands, legs, foot, and toes. Hands, particularly the thumbs, become more functional. Sexual organs distinguishing female or male are now clearly visible.Īrms have almost reached final proportion and length, though legs are still quite short relative to fetus' body. Lungs develop further as the fetus inhales and exhales amniotic fluid, which is essential for air sacs within lungs to function properly.įully functional spleen will assume functions supervised by liver such as removal of old red blood cells and production of antibodies. Heartbeat can be detected with external instruments. Sucking muscles of mouth fill out cheeks, tooth buds continue to develop and salivary glands begin to function. It may now extend above the pubic bone (pubic symphysis) which can be felt on palpitation.įetal head is about one-half of the crown-to-rump length and rests on a well-defined neck instead of shoulders.
Mother's size: Uterus is growing too large to remain completely within the pelvis.
Weight: between 0.3 and 0.5 ounce (8 to 14g). Week 18-20 An ultrasound will be offered. The second trimester maternal serum screening will be offered at this time if the first trimester test was not done (see week 12).
Eyelashes and eyebrows have appeared, and the tongue has tastebuds. Length is a better measure at this time than fetal weight. Week 16 The fetus is around 14 cm in length. Length: The crown-to-rump length almost 2.5 inches (61mm).