What is the lengh of pregnancy on average?
40 weeks
What is the date called that someone is due to give birth?
The EDD (estimated due date) or delivery date
What is considered a term pregnancy?
37 - 42 weeks
What is considered preterm birth?
Before 37 weeks
What is considered post-term?
After 42 weeks
When is the first trimester?
Under 14 weeks
What is considered the second trimester?
14 - 26 weeks
What is considered the third trimester?
27 - 40 weeks
How do we calculate gestational age?
How does the amniotic sac prevent parturition?
Prostaglandins are not released
How does the cervix ripen?
What factors maintain the pregnant state?
What does stage 1 of labour involve?
Cervix relaxes, causing it to dilaate and thin out
What does stage 2 of labour involve?
Uterine contractions increase in strength and infant is delivered
What does stage 3 of labour involve?
Placenta is expelled
What maintains the quiescent uterus?
Progesterone and relaxin
What causes the uterine ‘awakening’?
Increase in gap junction connectivity (prostaglandins), increase in oxytocin receptor numbers (estrogen)
What triggers the oxytocin release?
Ferguson reflex
What hormone causes the epulsion of the placenta and the final uterine contractions?
Oxytocin
What are the 2 phases in the first stage of labour?
Latent phase - <4 cm Active phase - 4 - 10 cm (fully) - Rupture of membranes
How much do we expect the baby to move per hour in the active phase?
1 cm per hour
What are the 7 stages in the 2nd stage of labour (essentially pushing out the baby)?
What is the difference in engagement between someone who has given birth before and someone who is having their first birth?
Engagement happens a lot closer to birth in someone who has given birth before
What are some examples of abnormal presentations of the baby?