Talk:BGDA Practical 12 - Birth
From Embryology
Practical Audio
BGD Cycle A 2010 Audio - Dr Mark Hill Monday 17th May 2010 3-5pm G2G4.
listen Part 6 | download (2.13 Mb MP3 18:36) |
Hormones | Roles |
---|---|
Progesterone |
|
Estrogens |
|
Oxytocin |
|
Prostaglandins |
|
Endocrine | Birth |
Labour Stages
Labour Stages | Changes | Roles |
---|---|---|
Stage 1 | dilatation | uterine contractions 10 minutes apart, function to dilate cervix fetal membranes rupture releasing amnion, 7 -12 hours (longer for first child) |
Stage 2 | expulsion | uterine contractions push fetus through cervix and vagina, contractions 2-3 minutes apart, 20 - 50 minutes |
Stage 3 | placental | following child delivery contractions continue to expel placenta. haematoma separates placenta from uterine wall, separation occurs at spongy layer of decidua basalis, 15 minutes |
valign=top Stage 4 | recovery | continued myometrial contraction closes spiral arteries, 2+ hours |
Hormones | Roles |
---|---|
Progesterone |
|
Estrogens |
|
Oxytocin |
|
Prostaglandins |
|
Endocrine Development |
External Environment
- mainly shown in other species parturition occurs in peaceful undisturbed surroundings, stress may have an inhibitory effect on oxytocin release
- Most human births occur at night (peak at 3am) diurnal rhythm influence