During these first 8 weeks, our baby is in what we call the embryonic stage. Physiologically, babies begin to develop the beginnings of limbs, which will result in their arms and legs. Their height reaches 9 mm at the end of the first month and weighs 0.5 grams. The first internal organs are formed, including the heart, which begins to beat on the 25th day, and lungs. At the same time, the neural tube begins to form which becomes the brain and spinal cord. […]