Template:Birth stages table
From Embryology
| Labour Stages | Changes | Time | Roles |
|---|---|---|---|
| Stage 1 | Dilatation | 7 to 12 hours longer for first child |
Uterine contractions 10 minutes apart, function to dilate cervix fetal membranes rupture releasing amnion. |
| Stage 2 | Expulsion | 20 to 50 minutes | Uterine contractions 2 to 3 minutes apart, function to push fetus through cervix and vagina. |
| Stage 3 | Placental | 15 minutes | Uterine contractions following child delivery expel placenta. Haematoma separates placenta from uterine wall, separation occurs at spongy layer of decidua basalis. |
| Stage 4 | Recovery | 2+ hours | Uterine contractions continue and myometrial contraction closes spiral arteries, also begins to reduce uterine volume. |
