Placenta praevia Flashcards
What is placenta praevia?
A placenta that is lying partly or wholly in the lower uterine segment and is over the internal cervical os
What is a low lying placenta?
A placenta that is within 20mm of the internal cervical os
What are the risk factors for placenta praevia?
Previous C-section
- Embryos are more likely to implant on a lower segment section scar
Previous placenta praevia
Older maternal age
Smoking
Structural uterine abnormalities e.g fibroids
Assisted conception
What is the presentation of placenta praevia?
Painless vaginal bleeding (usually after 36 weeks, but suspect placenta praevia after 24 weeks)
When is placenta praevia usually picked up?
At the 20 week anomaly scan
How should placenta praevia be monitored?
Repeat transvaginal ultrasound at:
- 32 weeks
- 36 weeks
What does placenta praevia increase the risk of?
Emergency caesarean section
Antepartum haemorrhage
Emergency hysterectomy
Maternal anaemia
Preterm birth
Low birthweight
Stillbirth
What are the different grades of placenta praevia?
Grade 1 - placenta is in the lower uterine segment, but has not reached the internal os
Grade 2 - the placenta is reaching, but not covering the internal os
Grade 3 - the placenta is partially covering the internal os
Grade 4 - the placenta is completely covering the internal os
What is the management of placenta praevia?
Steroids given between 34 and 35+6 weeks gestation
Give advice about pelvic rest - no penetrative sex
Planned caesarean considered between 36 and 37 weeks
Emergency C section if antenatal bleeding or premature labour
What is the management of bleeding with an unknown placental position?
ABCDE approach
Urgent transvaginal ultrasound
If bleeding is not controlled, emergency C section required
What is the investigation of choice to exclude placenta praevia?
Transvaginal ultrasound
What is the management of placenta praevia in a woman in labour?
Caesarean section
