Chapter 19 - Birth And Infant Development

Question 1

What is gestation and parturition?

Answer 1

Gestation - the time the baby is in the uterus (pregnancy)

Parturition - birth, and the short amount of time leading up to it

Question 2

What occurs during the first stage of labour?

Answer 2

• contractions occurring every 30 minutes (the beginning of the birth process and the contractions are referred to as labour pains.
• dilation of the cervix - allowing the baby to move more deeply into the pelvis
• waves of contractions travel from the upper part of the uterus downward towards the cervix
• the uterus, cervix and vagina form a single passage called the birth canal.
• complete dilation of the cervix marks the end of the first stage of labour

Question 3

What occurs during the second stage of labour?

Answer 3

• stage of expulsion
• the breaking of waters usually occurs at the beginning of the second stage of Labour
• the head of the baby stretches the mother’s vagina
• the baby’s head turns to face the mother’s back
• with each contraction, the baby’s head becomes more and more visible through the vagina
• the the bones of the skull may be slightly smushed but resumes shape a few days after birth

Question 4

What occurs during the third stage of labour?

Answer 4

• the baby begins to breath
• the amnion, chorion and placenta are still inside the uterus at this stage
• the umbilical cord is cut and falls away after a few days
• the baby is covered in vernix and is gently washed to prevent incidences of skin infections
• the uterus continues to contract until the placenta and other membranes are expelled (after birth)
• infection can occur in the uterus

Question 5

What are some characteristics of a newborn infant?

Answer 5

• the head makes up a quarter of the overall length and the legs make up a third
• muscle control has not developed
• it can breath, suck, swallow, see, hear, smell, get rid of wastes and cry
• natural reflexes such as grabbing and sucking

Question 6

What is a ductus venosus?

Answer 6

A vessel that bypasses the liver and connects straight to the inferior vena cava

Question 7

What is a ductus arteriosus?

Answer 7

A lung bypass that allows blood in the pulmonary artery to flow directly into the aorta.

Question 8

What changes occur in the mother after birth?

Answer 8

• over roughly 8 weeks, the uterus and repro organs slowly return to their original state/size. This period of time is called puerperium.
• the blood volume returns to normal
• pulse becomes slower
• body temperature becomes slightly above normal.
• depression may occur
• menstruation returns usually after the 20th week of breast feeding or 10th week after birth

Question 9

Explain the structure of the breasts

Answer 9

• during puberty, the nipples on girl’s bulge and start to develop. Boy’s do not go through this change.
• 16-25 lobes divided into a number of lobules in each breast
• each lobule is made up of glandular alveoli which secrete milk
• fatty connective tissue give the breasts their shape
• each lobule has a duct and milk space that leads to the exterior

Question 10

What is lactation?

Answer 10

The initiation and maintenance of milk secretion

• a day or two after birth milk secretion begins
• first secretions are called colostrum (yellowish, white, watered liquid)
• colostrum contains little to no fat and contains a high content of the mother’s antibodies
• when the nipples are sucked, an automatic response called the milk let-down reflex is triggered and milk begins to flow
• the brain instructs the pituitary gland to realise oxytocin
• 1.5L of milk may be produced each day
• dietary requirements are calcium, phosphate and vitamin D