Hormonal control of birth

Question 1

Define birth

Answer 1

the emergence of an individual from the body of its parent

Question 2

Outline the process of birth

Answer 2

1. Relaxins is released which softens
   and widens the cervix
2. Amniotic sac burst, releasing fluid
3. Baby comes out
4. Placenta is expelled (after birth)

Question 3

Describe how oestrogen, ocytocin and progesterone plays a role in the hormonal control birth in step 1

Answer 3

Oestrogen and progesterone sharply decrease. Placenta begins to produce prostaglandins, causes uterus to contract as increased sensitivity to oxytocin

Question 4

Describe the second step of hormonal control of birth

Answer 4

• Contracting uterus stretches cervix
  Stimulates production of oxytocin from hypothalamus
• Oxytocin stimulates more uterus contractions and production of prostaglandins
  (positive feedback loop) cycle keeps increasing

Question 5

Describe the third step of hormonal control of birth

Answer 5

Once the cervix increases full dilation, oxytocin and adrenaline work together for final contraction.

Question 6

Describe the fourth step of hormonal control of birth

Answer 6

Baby gets delivered
Oxytocin maintains uterine contractions and promotes mothers instinct

Question 7

Describe the fifth step of hormonal control of birth

Answer 7

Prolactin + oxytocin works together to stimulate lactation (production of milk)