Tutorial 6: Antepartum Haemorrhage Flashcards
What is antepartum Haemorrhage?
Bleeding from the genital tract after 24 weeks gestation.
Affects 3 – 5% of pregnancies.
What are the general principles when managing bleeding?
- Admit
- ABC’s – IV access and resuscitate with fluids, give O2
- Bloods - FBC, coags (?DIC)
- Group and hold
- Assessment and diagnosis and
- Anti-D if Rhesus negative
What are common causes/ddx of antepartum haemorrhage?
Common APH:
- Undetermined 40%
- Placental abruption (bleeding, pain)
- Placenta Previa (painless, recurrent bleeding)
- Edge Bleeding (painless bleeding w. Nil findings)
Rarer APH:
- Incidental genital tractpathology
- Uterine rupture
- Vasa praevia
- Local lesion: painless, minor bleeding
- findings: cervical lesions
What is Placenta Previa?
Placenta implanted in the lower segment of the uterus.
What is the epidemiology of placenta previa?
Complicates 0.4% of pregnancies at term.
At 20/40, many more women (~28%) will have a “low-lying” placenta seen on USS which will rise away from the cervical os as the pregnancy continues, due to the growth of the lower segment.
What are the two types/classifications of placenta previa?
-
Major:
- placenta covers the internal OS
- ALWAYS requires c-section
-
Minor/Marginal:
- placenta is in the lower segment, but doesnt cover the internal os
- possibility of normal delivery
What are some risk factors for placenta previa?
- Previous uterus surgery (Caesarean)
- Multiple pregnancy
- High parity
- Increasing Age
- Fibroids (disrupts placentation)
What are some slinical features/symptoms of placenta previa?
- May be none of note (33%).
- Typically painless, intermittent bleeds over several weeks. Bleeds can be severe.
What are some commong examination findings of placenta previa?
- Breech presentation
- Transverse lie
- Head not engaged and high.
Do not perform a vaginal examination until placenta previa has been excluded, as this may exacerbate her bleeding/blood loss
What initial examination should be avoided in a woman with antepartum haemorrhage?
IMPORTANT: Avoid VE (vaginal examination) in women with APH before placenta praevia has been ruled out
- as this can exacerbate severe bleeding.
- → Placenta praevia may be asymptomatic and is often an incidental finding on ultrasound scan.
What investigations should be performed in a woman with placenta previa?
Second trimester USS: can usually see a low-lying placenta
- This scan should be repeated at 34 weeks to assess if placenta praevia present.
- NB: Transvaginal USS more sensitive.
If currently bleeding:
- CTG: to assess fetal wellbeing (Fetal distress is uncommon)
- FBC, coags etc.
What is the management of placenta previa?
Management if bleeding:
- Admit
- Bloodwork (group and hold, FBC, coags) available for transfusion if needed.
- Managing shock and observation can allow the pregnancy to be prolonged.
- May require emergency delivery, and administration of steroids.
Management if Asymptomatic:
- Can be managed at home (if circumstances good/ easy hospital access) with admit at 37 weeks.
Delivery for Placenta Previa (PP):
- Timing: All should be delivered at 39 weeks
-
Mode of delivery:
- minor PP can be considered for vaginal delivery
- otherwise or if in doubt then by Caesarean section.
What are some complications of Placenta Previa?
- Increased risk of PPH (lower segment of uterus does not contract so well)
- Placenta acreta may also occur: USS. Which may require:
- balloon compression or
- hysterectomy
What is placental abruption?
Part or all of the placenta separates from the uterus before delivery of the fetus.
-
At the site, blood accumulates between the placenta and uterus, which can result in further separation.
- The blood may t_rack between the membranes and myometrium_ to be revealed as APH
- Though it may also remain hidden in the myometrium resulting in no visible bleeding (20%).
What is the incidence of placental abruption?
Placental abruption affects 1% of pregnancies
- though many cases of APH have no identified cause which may be small abruptions, thus may be a higher figure.