The crown-to-rump length of your baby is about 1.25 to 1.68 inches (between 3.1 and 4.2cm). He weighs about 0.18 ounces (5g).
The placenta is now producing progesterone which helps to make nutrients for your developing baby.
Your baby has passed the stage when he is most susceptible to damage. By the end of this week, the danger zone for congenital abnormalities has passed.
The plan for your baby's body has been completely laid down by now. Further growth and cell division will build on this plan.
Taste and tooth buds have appeared.
Your baby has recently developed fingers and toes which are now well-formed. Ankles, wrists and the inner ear have formed. Your baby's nose is flat and his eyes are far apart. His eyes, ears, mouth and nose are all recognizable. The tail is disappearing.
Your baby is moving around the amniotic sac, and moving his feet and ankles. You still will not be able to feel these movements but you may be able to see them on an ultrasound.
Blood is circulating through the arteries and the vein of the umbilical cord.
The brain of your baby is developing at a phenomenal rate. About one quarter of a million new neurons are produced every single minute at this stage in your pregnancy.
If your baby is a boy, his testes, though they are not even clearly visible, are already producing testosterone.
Your baby is no longer called an embryo, but rather a fetus.Your Body This Coming Week
Your uterus is now about the size of an orange, but you still don't "show". However, you probably have noticed an increase in your breast size.
You may be having mood swings, feeling happy and elated one moment, crying the next. This is perfectly normal, caused by the changing hormones in your body as well as all the hopes and fears you have and the realization that your life will be forever changed by your pregnancy.
There is little increase in abdominal size during the first trimester, though you might be starting to see some weight gain. Hormonal changes, however, especially the increase of progesterone and relaxin can cause your joints and ligaments to soften as your body begins to prepare for birth.
The joints in your pelvic bones are widening now. This may cause you to feel unstable at times, even sometimes dropping things or bumping into things.