How The Skin Works: Structure And Functions, Diagrams, Diseases Of The Skin, Interesting Facts And Statistics. Neonatal . The neonatal period extends from birth to somewhere between 2 weeks and 1 month. Immediately after the baby is born, uterine contractions force blood, fluid, and the placenta from the mother's body. The pituitary gland is a small structure that affects many areas of your body and overall health. We’ll go over the anatomy and function of the pituitary gland, the hormones it stores and releases, and the kinds of conditions that can affect it.