 [ Symptoms ] what can i expect during week 6 of my pregnancy [ Disease ] 0baby  the embryo is starting to look like a tadpole it is about 0 08 inches to 0 16 inches    the size of a bb pellet    from the top of the head to buttocks this crown to rump length is used more often than crown to heel length because the baby is legs are most often bent and hard to measure the eyes and limb buds also are forming a heartbeat can sometimes be detected by an ultrasound around now this is also an extremely important time in the development of your baby since between 17 and 56 days the embryo is most susceptible to factors that can interfere with its normal growth mom to be  you may have gained a few pounds by now but if you are experiencing morning sickness you may have lost weight which is also normal you are starting to notice some changes in your body clothes getting a little tighter around the waist weight gain in your legs and breasts with a pelvic exam your practitioner will be able to notice a change in the size of your uterus tip for the week  make sure you are following good prenatal habits like eating right and taking your prenatal vitamins since the neural tube which is the beginning of the central nervous system has formed by now taking folic acid to prevent spinal cord defects such as spina bifida has been crucial if you have not already stop smoking and drinking