First Stage

It involves cervical dilation (opening up) and effacement (getting thinner). The “show” refers to the mucus plug in the cervix, which prevents bacteria from entering the uterus during pregnancy, falling out and creating space for the baby to pass through.

The first stage has three phases:

• Latent phase – from 0 to 4cm dilation of the cervix.
  • This progresses at around 0.5cm per hour.
  • There are irregular contractions (last for about 30 to 45 seconds and gradually increase in intensity and frequency, from around 20 minutes to five minutes apart)
• Active phase – from 4cm to 7cm dilation of the cervix.
  • This progresses at around 1cm per hour
  • there are regular contractions (last around 40 to 60 seconds and come about three to four minutes apart)
• Transition phase – from 7cm to 10cm dilation of the cervix.
  • This progresses at around 1cm per hour,
  • there are strong and regular contractions (are around 60 to 90 seconds long and occur about every two to three minutes.)

Delay in the first stage of labour is considered when there is either:

• Less than 2cm of cervical dilatation in 4 hours
• Slowing of progress in a multiparous women

Progress in the first stage of labour is monitored using a partogram

Partogram

Second stage

The second stage of labour lasts from 10cm dilatation of the cervix to delivery of the baby.

The success of the second stage depends on “the three Ps”: power, passenger and passage.  Delay in the second stage is when the active second stage (pushing) lasts over:

• nulliparous woman - >3 hours with epidural or >2 hours without
• multiparous woman >2 hours with epidural or >1 hour without.