Your fetus is now about the size of an avocado, measuring around 10-11 cm (4-4.3 inches) crown to rump and weighing about 100 grams (3.5 ounces). The baby is straightening up, working on lifting the head and neck. Movement is becoming more pronounced, with the arms and legs moving frequently. In the next three weeks, your baby will begin a significant growth spurt. Facial features are clearly discernible, and all the organs are perfectly formed, though they will continue to mature. Even sweat glands have formed! The baby may be sucking its thumb. If you have an ultrasound, it's often possible to determine the baby's sex at this stage.