ivillage @ 7 weeks

Your baby-to-be is the size of a small bean, measuring in at approximately 9 to 11 millimeters, crown to rump. Dark spots, mark the early formation of the eyes. Pits indicate the formation of nostrils and ears. Your baby's brain is developing rapidly, and limbs and facial characteristics are now forming. Your baby's heart now has a right and left chamber. An ultrasound may be able to detect heart motion. The esophagus and trachea are changing and differentiating into separate tubes, with lungs positioned on either side.