Labour is said to be prolonged when duration of latent stage of labour crosses:
labour pattern nullipara multipara prolonged latent phase >20 hrs >14 hrs protracted active phase dilatation <1.2 cm/hr <1.5 cm/hr protracted descent <1 cm/hr <2 cm/hr arrest of dilatation >2 hr >2 hr arrest of descent >1 hr >1 hr
12 hours
18 hours
20 hours
36 hours
Obstetrics