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The Newborn (2)

© Yasser Anathallee

Contunuing last week's article on the essential characteristics of a newborn, we will this week consider the chest, anogenital area, skeletal structure and muscles, all of which fall under the anatomical category.

(iv) The chest. The chest is bell-shaped and at birth is approximately the same circumference as the abdomen and less than the head. For this reason, it appears small. The thorax is almost circular. The infant uses the diaphragm and the abdominal muscles to exhale and inhale, and not the thoracic cage as do older children and adults. The breasts may be swollen because of the hormonal activity originating from the mother, and a pale, milky fluid can be expressed. The condition disappears in 2 to 4 weeks without treatment. On the abdomen, the umbilical stump begins to shrink and becomes discoloured soon after birth and turns black within a few days and sloughs off.

(v) Anogenital area. The infant's buttocks are plump, firm and pink. In the anal region, there should be no redness or fissures. In the male child, the size of the penis and the scrotum varies. The testes have usually descended into the scrotum by the eighth month of intrauterine life. The prepuce or foreskin of the penis may adhere to the glans. The female genitalia may be slightly swollen due to hormone activity originating from the mother. The vagina exudes a mucous discharge. During the first week, the latter may be blood-tinged. This is also caused by hormones transmitted from mother to baby and the condition should disappear by the second or third week.

(vi) Skeletal structure. The bones of the newborn are soft because they are composed mainly of cartilage. The skeleton is flexible and the joints are elastic. This ensures a safe passage through the birth canal. The infant's back is normally straight and flat. The legs are small, short and bowed. The soles of the feet nearly touch each other. The arms, like the legs, are relatively short. The hands are plump, the fingers relatively short, and the nails are smooth and soft and extend over the fingertips.

(vii) Muscles. Muscular contour in the healthy, plump infant is smooth and the muscles, feel hard and slightly resistant to pressure. The movements of the newborn are random and uncoordinated as the infant cannot control his muscles.