Antepartum haemorrhage Flashcards
Green
What is APH?
Genital tract bleeding from 24w
What are the common causes of APH?
Dangerous causes -Placenta praevia -Abruption -Vasa praevia Other uterine sources -Circumvallate placenta -Placental sinuses Lower genital tract sources -Cervical polyps, erosions, carcinoma -Cervicitis -Vaginitis -Vulval varicosities Fibroid complication e.g. torsion, rupture
What is placenta praevia?
Placenta lying in lower uterine segment, encroaching on or obstructing the cervical os
Does a low lying placenta in early gestation mean a normal birth is not possible?
As the uterus expands through gestation, the placenta may ‘move’ away from the os (uterine expansion causes this; not placental movement)
How many low lying placentas are praevia at term?
1 in 10
What are the post partum implications for mothers with placenta praevia?
Increased PPH risk
Lower segment of uterus less effective at contraction
How is placenta praevia classified?
Grannum classification
Marginal (types I-II), lower segment but does not cover the os
Major (types III-IV), partial or complete coverage of os
Is the bleeding always revealed in placenta praevia?
Yes (compared to abruption, which can be hidden)
What should be avoided in suspected placenta praevia?
Vaginal exam (bimanual or speculum) Penetrative intercourse
What is placenta praevia associated with?
CS Sharp curette TOP Multiparity Multiple pregnancy >40y Assistant contraception Other (deficient endometrium-manual removal of placenta, fibroids, endometritis)
What are the potential complications of placenta praevia?
Placenta praevia usually warrants CS due to obstruction of engagement
PPH
Development of placenta accreta or percreta (if not recognised, women in delivery may have major haemorrhage, necessitating hysterectomy)
What is typically seen in the Hx of placenta praevia?
Intermittent painless bleeds (increasing in frequency and time over several weeks)
What would be seen on examination?
If suspected - do not perform vaginal exam
Breech presentation/transverse foetal lie are common
How can a placenta praevia be diagnosed?
USS (normally diagnosed at second trimester USS, but repeated at 32w if major, 36w if minor to see if placenta has moved)
If placenta <2cm from os on second scan, unlikely to move by delivery
Which women with placenta praevia should be admitted?
All
Keep blood on standby and give anti-D to Rh-ve
Steroids should be given in <34w
How should the baby be delivered in placenta praevia?
If major - Delivery by CS
If minor - aim for normal unless the placenta is within 2cm of os (esp if placenta posterior/thick)
If CS is indicated for placenta praevia, when should it be performed?
CS with consultant attendance at 38w
If 36-37w give steroid cover and have crossmatched blood available, if accreta suspected
What is placenta accreta?
Placentation into the myometrium of the uterus; causes difficulties in removal due to extreme adherence postpartum
What is placenta percreta?
Placentation beyond myometrium, including into surrounding pelvic organs e.g. bladder, bowel etc. Managed in interventional radiology (coils used to clot off supportive vessels)
What is vasa praevia?
Foetal blood vessel running in the membranes in front of presenting part (usually from umbilical cord being attached to membranes rather than placenta)
CS needed
What is placental abruption?
Part or all of placenta separates before delivery of foetus
How common is abruption?
1%
Do abruptions present with bleeding?
Not always; some may enter the myometrium or liquor rather than being lost through the os (haemorrhage is absent in 20%)
What are risk factors for placental abruption?
IUGR Pre-eclampsia HNT (pre-existing) Smoking Previous abruption PROM Multiple pregnancy Polyhydramnios Inc maternal age Thrombophilia Abdo trauma Drug use (esp cocaine/amphetamine) Infection
