Antepartum Haemorrhage Flashcards
Define antepartum haemorrhage
APH is defined as any vaginal bleeding from 24 weeks gestation until delivery. Bleeding that occurs within the first 24 weeks of gestation is known as bleeding in early pregnancy.
Problems with the placenta in APH can be divided into … (3)
. Problems with the placenta in APH can be divided into placental abruption, placenta praevia and vasa praevia.
Placental abruption refers to …
Placental abruption refers to either partial or complete separation of the placenta from uterus prior to delivery.
Placental abruption
In placental abruption, bleeding may be obvious or concealed behind the placenta. Previous placental abruption is the most significant risk factor. Modifiable risk factors include cocaine, amphetamine and tobacco use, all should be discouraged to reduce rates of placental abruption (as well as other pregnancy complications).
The main risk factors for placental abruption are listed:
Previous abruption
Preeclampsia
Intra-uterine growth restriction
Non-vertex presentation
Polyhydraminos (raised liquor volume)
Older mother
Multiparity
Low BMI
Assisted reproduction
Intrauterine infection
Abdominal trauma (consider domestic violence)
Smoking
Cocaine/amphetamine use
Placenta … refers to a placenta that is near or covering the internal cervical os within the lower segment of the uterus.
Placenta praevia refers to a placenta that is near or covering the internal cervical os within the lower segment of the uterus.
Traditionally, placenta praevia could be divided into major (complete) or minor (partial) depending on the…
The distance from the internal cervical os.
Major/Complete: placenta lies over the internal cervical os.
Minor/Partial: leading placental edge is in the lower uterine segment but not covering the os.
Placentas are often low at what week scan?
Placentas are often low at the 20-week anomaly scan. Women with low placentas will be re-scanned at around 32 weeks gestation to confirm whether the placenta remains low. If the placenta covers the internal cervical os or the placental edge is within 2cm of the os, the foetus will need to be delivered by caesarean section.
Main risk factors for placenta praevia are listed:
Previous C-Section
Previous TOP
Deficient endometrium (secondary to uterine scar, endometritis, curettage, etc)
Multiparity
Age > 40yrs
Multiple pregnancy
Smoking
Assisted reproduction
Define vasa praevia
Vasa praevia is defined as the presence of fetal placental vessels lying over internal cervical os.
The typical history of an APH associated with vasa praevia is bleeding from …
The typical history of an APH associated with vasa praevia is bleeding from spontaneous rupture of membranes (SROM). It is fetal, not maternal, blood that is lost in vasa praevia. Additionally, given the baby’s small blood volume, relatively small bleeds can be fatal.
There are two major types of vasa praevia:
Type 1: due to a velamentous cord - where the cord inserts into the chorioamniotic membrane with vessels not protected by Wharton’s jelly or the placenta and crossing the cervical os.
Type 2: due to a bilobed or accessory placenta with connecting vessels that cross the cervical os.
The severity of APH is dependent on the extent of blood loss and clinical signs of shock.
Minor APH: < 50 mls and stopped
Major APH: 50-1000 mls, no sign of shock
Massive APH: > 1000 mls or signs of shock.
History taking in APH
When?
What?
Fresh red - new bleed
Dark brown - old blood
Mucous - think cervical plug
Associated with waters breaking? (think vasa praevia)
Quantity? (i.e. spotting, cupful, soaked clothing)
Provoked by sexual intercourse?
Abdominal Pain?
Confirm placental position on last scan.
Examination in APH
Basic observations: are there features of shock?
Abdominal palpation: does the uterus feel stony hard suggesting abruption?
Speculum: is the source obvious in vagina, on cervix or coming through external os?
Consider cervical assessment: is this early labour?
Do not perform vaginal examination if known placenta praevia.
