Obstetrics and Gynaecology
Antepartum Haemorrhage and Multiple Pregnancy
Placenta praevia, abruptio placentae and multiple pregnancy for MBBS, with chorionicity and twin complications, mapped to NMC codes OG10 and OG11.
MedNext Academy | 3 min read
Antepartum Haemorrhage and Multiple Pregnancy
Placenta praevia, abruptio placentae and multiple pregnancy for MBBS, with chorionicity and twin complications, mapped to NMC codes OG10 and OG11.
This chapter covers bleeding in later pregnancy and the special problems of carrying more than one foetus. It contrasts placenta praevia and abruptio placentae in presentation and management, explains the importance of confirming placental site before vaginal examination, and details chorionicity, twin-to-twin transfusion and the delivery risks of multiple pregnancy.
High-yield: Antepartum Haemorrhage and Multiple Pregnancy
- Antepartum haemorrhage is bleeding from the genital tract after 24 weeks and before the birth of the baby.
- The two major causes are placenta praevia and abruptio placentae, and they differ sharply in presentation.
- Placenta praevia classically causes painless, causeless, recurrent bright red bleeding with a soft, non-tender uterus.
- Abruptio placentae causes painful bleeding with a tense, tender uterus and often foetal distress or death.
- In suspected placenta praevia, vaginal examination is avoided until placental location is confirmed by ultrasound.
- A low-lying placenta on the anomaly scan is rechecked in the third trimester, as many migrate upward.
- Concealed abruption can present with shock out of proportion to visible bleeding and may cause disseminated intravascular coagulation.
- A Couvelaire uterus is bruised, boggy myometrium from blood extravasation in a severe abruption.
- Twin pregnancy is dichorionic diamniotic, monochorionic diamniotic or monochorionic monoamniotic, and chorionicity is best determined by first-trimester ultrasound.
- Monochorionic twins can develop twin-to-twin transfusion syndrome due to shared placental vessels.
- Multiple pregnancy raises the risk of preterm labour, pre-eclampsia, anaemia, malpresentation and postpartum haemorrhage.
- The lambda or twin-peak sign on ultrasound indicates dichorionicity, while the T sign indicates monochorionicity.
- Monoamniotic twins share one sac and are at high risk of cord entanglement, needing close surveillance and early delivery.
- Delivery planning in twins depends on chorionicity and the presentation of the first (presenting) twin.
Praevia versus abruption
- **Placenta praevia:** Painless, recurrent, bright red bleeding; soft non-tender uterus; avoid vaginal exam until scan done.
- **Abruptio placentae:** Painful bleeding; tense tender uterus; foetal distress; risk of DIC.
- **Concealed abruption:** Shock out of proportion to visible bleeding; Couvelaire uterus.
- **Chorionicity:** Lambda sign = dichorionic, T sign = monochorionic. Best judged in the first trimester.
NMC competencies in this chapter
- **OG10.1:** Placenta praevia: recognition, classification and management
- **OG10.2:** Abruptio placentae: emergency diagnosis, DIC and delivery
- **OG11.1:** Multiple pregnancy: chorionicity, complications and delivery planning
Frequently Asked Questions
How do placenta praevia and abruption differ?
Praevia gives painless, recurrent bright red bleeding with a soft uterus, while abruption gives painful bleeding with a tense, tender uterus and often foetal compromise and coagulation failure.
Why avoid a vaginal examination in antepartum haemorrhage?
Until ultrasound confirms the placenta is not low-lying, a digital examination could provoke torrential bleeding from a placenta praevia, so location is confirmed first.
How is chorionicity in twins determined?
By first-trimester ultrasound: the lambda or twin-peak sign indicates dichorionic twins and the T sign indicates monochorionic twins, which carry higher risks.
What is twin-to-twin transfusion syndrome?
In monochorionic twins, shared placental vessels can shunt blood unequally, leaving one twin over-perfused and the other under-perfused, needing specialist surveillance and sometimes laser treatment.
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