Placenta praevia Flashcards
(15 cards)
What is placenta praevia?
Where the placenta is attached in the lower portion of the uterus, lower than the presenting part of the fetus.
What is the difference between low lying placenta & placenta praevia?
Low lying placenta is used when the placenta is within 20mm of the internal cervical os. Placenta praevia is used only when the placenta is over the internal cervical os.
What are the 3 main causes of antepartum haemorrhage?
- Placenta praevia
- Placental abruption
- Vasa praevia
What are causes of minor bleeding or spotting in pregnancy?
Cervical ectropion, infection, vaginal abrasions from intercourse or procedures.
What are the risks of placenta praevia?
Antepartum haemorrhage, Emergency C section, Emergency hysterectomy, Maternal anaemia & transfusions, Preterm birth & low birth weight, Stillbirth.
What are the risk factors for placenta praevia?
Previous C sections, previous placenta praevia, older maternal age, maternal smoking, structural uterine abnormalities (e.g., fibroids), assisted reproduction (e.g., IVF).
When is the placenta position assessed?
20 week anomaly scan.
How do you grade placenta praevia?
- Minor praevia/grade I - the placenta is in the lower uterus but not reaching the internal cervical os.
- Marginal praevia/grade II - the placenta is reaching the internal os but not covering it.
- Partial praevia/grade III - the placenta is partially covering the internal cervical os.
- Complete praevia/grade IV - the placenta is completely covering the internal os.
How does placenta praevia present?
Many women are asymptomatic. May present with painless vaginal bleeding in pregnancy (antepartum haemorrhage). Bleeding usually occurs later in pregnancy (around or after 36 weeks). No pain, fetal heart usually normal.
How is placenta praevia diagnosed and what should be avoided?
Digital vaginal examination should not be performed before an USS as it may provoke a severe haemorrhage. Often picked up on the routine 20 week abdominal exam. TV USS is recommended as it improves the accuracy of placental localisation and is considered safe.
What is the management if the diagnosis is made at the 20 week scan?
Repeat transvaginal scan at: 32 weeks gestation & 36 weeks gestation.
What should you give between 34 and 35 + 6 weeks gestation?
Corticosteroids to mature the fetal lungs in case of preterm delivery.
What early delivery is planned?
Considered between 36 and 37 weeks gestation which is planned early to reduce the risk of spontaneous labour and bleeding. Planned C section is required.
How do you manage the complication of haemorrhage?
Emergency C section, Blood transfusions, Intrauterine balloon tamponade, Uterine artery occlusion, Emergency hysterectomy.
