birth and first breath

Question 1

progesterone

Answer 1

inhibits uterine contractility
-prevents fetal expulsion
promotes cervical plug development
-provides microbial barrier

Question 2

oestrogen

Answer 2

promotes connexion insertion between myometrial cells
stimulates oxytocin receptor insertion into myometrium
-unified strong uterine contractions
increases prostaglandins(PGE2) production
-softens the cervix

Question 3

relaxin

Answer 3

softens cervic-preparation for labour

softens pelvic ligaments -preparation for delivery

Question 4

1st stage of labour

Answer 4

cervix stretched to full dilation
contractions are painful
oxytocin stimulates further uterine contraction both directly and indirectly via PGF2a
release of oxytocin by positive feedback

Question 5

prostaglandins

Answer 5

part of the eicosanoid system :
-local hormones for cell signalling 
-derived from arachidonic acid 
short lived:
-synthesized and released almost instantly 
multiple actions-in labour/delivery 
-PGE2 relaxes cervix 
-PGF2a contracts uterus

Question 6

2nd stage of labour

Answer 6

• delivery of fetus

- combination of uterine contraction and maternal effort

Question 7

3rd stage

Answer 7

delivery of the placenta after shearing off
uterine contraction compresses vessels to produce haemostasis
synthetic oxytocin or PGF2a used to enhance uterine contractility to treat post partum bleeding