Labour Flashcards
how many stages of labour are there?
how long do each last?
1st stage: 8 hours (can be 18)
- latent phase
- active phase
2nd stage: 5 hours
3rd stage: 5 hours
explain whats going on in the 1st stage latent phase & active phase of 1st stage of labour
latent phase
there is not much happening in regard to progression. The cervix dilates from 0 to 4cm, but the duration of this cannot be easily estimated. It is often a very long period, especially in women having their first baby
active phase
4cm cervical dilation to full dilation, at 10cm
The cervix should dilate at the rate of 0.5 – 1cm per hour,
explain the 2nd stage of labour?
how long for primigravidas and multiparous?
This is the stage from full dilatation of the cervix to delivery of the baby, and occurs within 3 hours for primigravidas (a woman who is pregnant for the first time) or 2 hours for multiparous (often much quicker)
what is the 3rd stage of labour?
This is the stage of labour after delivery of the baby to the delivery of the placenta and membranes, and usually occurs within 30 minutes of fetal expulsion.
what are the different ideas of why labour starts? [3]
Is it the fetus?
Is it progesterone withdrawal?
A role for corticotropin-releasing hormone?
what is a normal term for pregnancy? [1]
what is pre-term? [1]
what is a normal term for pregnancy? [1]
37-42 weeks
what is pre-term? [1]
>37 weeks
explain what happens during week 36-37 of normal pregnancy to the position of the fetus? [1]
explain what happens to position of baby during labour
36-37 weeks is when fetal head will descend into the pelvis.
the head descends as women enters proper labour
hey need to come out with the posterior part of the head as it is the narrowest bit, so they have to tuck their head and flex slightly
as well as turn their body, then once the head is mainly out they extend their neck (5), rotate again (6) and then come out (7)
why must the fetal head rotate during labour?
The suboccipitaobregmatic is the narrowest part of the fetal skull in most babies, and therefore has to exit the pelvis first. Tucking the head in allows the baby to come out with the back portion of its head
Then, once the fetus has passed via the interspinous distance with its head flexed slightly, the widest diameter of the pelvic canal changes from the transverse diameter of the pelvic inlet to the AP diameter at the pelvic outlet.
To obtain the best fit for the fetal head, the longest diameter of the fetal head passes through the widest diameter of the pelvis. Therefore the head must rotate during labour.
which is the most common position of fetal head position during pregnancy?
Occiput anterior (OA on diagram), is the most usual position for a baby to come out, with the occiput of the fetal skull facing anteriorly.
Occiput posterior is when the baby comes out with its head the opposite way
LOT = Left occiput transverse, which is when the baby comes out transversely with the occiput facig the left.
LOA is left-occipito anterior which is a diagonal between normal and transverse
ROP = Right occiput posterior
describe the position of the head for it to be expelled at narrowest part of skull x [1]
head flexed inwards (A) so that is 9.5 cm
what is cervical ripening?
what is it due to? [1]
what is the physiological change that occurs? [2]
cervical ripening
- increased softening, distensibility, effacement and dilatation of the cervix, before labour is due to alterations in the biomechanical properties of cervical tissue.
- rearrangement and realignment of collagen - also increases water content
what is bishops score?
Bishops score is used in early labour to think about how dilated the cervix is, based on the parameters listed. Useful to understand how far into pregnancy a woman is.
label each stage of labour shown
- Engage
- Flex and descend
- Full dilatation
- Internal rotation then extension
- External rotation
- Expulsion
why should you not pull on the placenta during 3rd stage of labour?
You shouldn’t pull on the placenta too hard as you could possibly cause uterus to prolapse, and send a woman into shock.
