Labour

Question 1

How do the hormone changes prior to labour affect the body?

Answer 1

1. Cause ligaments of pelvis to soften, making them more pliable for childbirth.
2. Increase response of uterus to stimuli and strengthen contraction of its muscles

Question 2

What position is the foetus in before labour begins?

Answer 2

1. Probably settled with its head in mother’s pelvis.
2. Cervix has softened, shortened in length, and likely to have begun to open a little.
3. Usually facing woman’s right/left hip bone, with knees drawn up to abdomen and legs crossed - Takes up as little room as possible.
4. One side of its head is usually pressed against mother’s bladder, other against her bowel

Question 3

What happens to the uterus during the final three months of gestation?

Answer 3

Undergoes weak, irregular contractions - gradually become stronger/ more frequent during last weeks of pregnancy

Question 4

What marks the beginning of the birth process?

Answer 4

1. Eventually contractions become strong and occur ~ every 30 minutes.
2. This is beginning of birth process and contractions are known as labour pains

Question 5

What is the first stage of labour?

Answer 5

1. The dilation of the cervix - time from the onset of labour to complete dilation (or opening) of cervix.
2. Variable in length - lasts an average of 8/9 hours if woman’s 1st child and ~ 4 hours for birth of subsequent children

Question 6

Describe the contractions that occur during the first stage of labour?

Answer 6

1. Waves of contraction travel from upper part of uterus downward towards cervix.
2. Each contraction = muscle fibres making up uterus shorten a small amount, pulling on cervix.
3. Shortens cervix so it no longer projects down into the vagina.
4. The cervix is opened. Cervical dilation allows foetus to move more deeply into the pelvis

Question 7

What happens during the first stage of labour as the contractions become more frequent and stronger?

Answer 7

1. Foetus’ head is pushed more forcefully against slowly dilating cervix.
2. Eventually cervix is completely dilated (~10 cm), and uterus, cervix and vagina form a single, curved passage.
3. Birth canal - route through which foetus will pass, aided by uterus + voluntary contractions of mother’s abdominal muscles.
4. Complete dilation of the cervix marks the end of the first stage of labour.

Question 8

What is the second stage of labour?

Answer 8

Stage of expulsion - involves the delivery of the foetus

Question 9

How does the second stage of labour begin?

Answer 9

1. Usually begins with bursting of membrane surrounding foetus and gush of fluid from vagina.
2. May occur earlier in labour or, may not occur until foetus is ready to be born

Question 10

How long does the second stage last?

Answer 10

From full dilation of the cervix to birth, lasts from 20 minutes to 2 hours.

Question 11

What is the foetus doing during the second stage of labour?

Answer 11

1. Foetus moves through fully dilated cervix, its head stretches the vagina.
2. Distension of vagina stimulates woman to contract her abdominal muscles.
3. These contractions + uterus contractions, push foetus through vagina.
4. As this occurs, baby’s head turns to face towards mother’s back.

Question 12

What happens during the second stage of labour?

Answer 12

1. Each contraction = head advances small amount.
2. Between contractions retreats a little, but overall head gradually moves through external opening of vagina.
3. As this occurs, more of head becomes visible.
4. During this time, mother’s pulse rate increases/ usually begins to sweat from effort required.
5. Between contractions mother tries to rest a little, to gain strength for the next effort.
6. Eventually head stretches vaginal entrance, tissues between it, anus - becomes tightly stretched over foetus’s head as forced into world.

Question 13

What happens to the foetus once the head has emerged?

Answer 13

1. It turns sideways again to face mother’s hips.
2. Allows shoulders and rest of body to move more easily through birth canal.

Question 14

What happens as the foetus passes through the birth canal during the second stage of labour?

Answer 14

1. The pressure on head may push it out of shape.
2. Underlying brain is not damaged, as bones of skull are pliable and separated by joints that allow some degree of overlap.
3. Head resumes its normal shape a few days after birth.

Question 15

How is the head positioned during the second stage of labour?

Answer 15

1. Head-down position allows foetus to begin breathing even before completely free of birth canal.
2. Allows head to be delivered 1st/ act as a wedge to force open cervix/ vagina.

Question 16

What happens during the third stage of labour?

Answer 16

1. Once born, baby begins to breathe with own lungs, even though still connected to placenta by umbilical cord.
2. Amnion, chorion and placenta are still inside uterus at this stage.
3. The umbilical cord is clamped, tied in two places, and then cut between the ties.

Question 17

What happens to the umbilical veins and arteries during the third stage of labour?

Answer 17

1. Arteries/vein within umbilical cord contract, either before/ immediately after they’re cut.
2. After a few days, stump of cord dries up and falls away - umbilicus is all that remains

Question 18

What is the afterbirth?

Answer 18

The uterus continues to contract, ~ 5 mins after placenta delivery, other membranes/ remains of umbilical cord are expelled.

Question 19

How is blood loss prevented during afterbirth?

Answer 19

1. The placental blood vessels constrict.
2. Uterus contractions squeeze shut uterine vessels that supply blood to placenta.
3. Blood clots then form to stop all leakage of blood - large area of exposed tissue = infection