8.2 Late Pregnancy Bleeding Flashcards
What are the causes of late pregnancy bleeding?
- Pregnancy specific: Placenta praevia, placental abruption, vasa praevia, uterine rupture, morbidly adherent placenta, excessive show (non-pathological)
- Unrelated: Cervical lesions (polyps/ectropion), trauma to genital tract (e.g. lacerations), lower genital tract infections, genital tract malignancies
what is the definition of late pregnancy bleeding?
Late pregnancy bleeding is defined as bleeding from the genital tract > 24 weeks gestation until delivery (antepartum haemorrhage/APH)
what are maternal complications of late pregnancy bleeding?
PPH, anaemia, infection, maternal shock, renal tubular necrosis, consumptive coagulopathy, prolonged hospital stay, psychological sequelae, complications of blood transfusion
what are foetal complications of late foetal bleeding?
Foetal anaemia & hypoxia, SGA/IUGR, prematurity (iatrogenic/spontaneous), hypoxic ischaemic encephalopathy, foetal death
What is the definition of placenta praevia>
Placenta praevia is defined as partial or full insertion of the placenta into the lower uterine segment (LUS)
what is considered Grade I placenta praevia minor?
Placenta encroaches LUS but does not reach cervical os
what is considered Grade II placenta praevia minor?
Placenta reaches cervical os but does not cover it
what is considered Grade III placenta praevia major?
Placenta covers part of the cervical os
what is considered Grade IV placenta praevia major?
Placenta completely covers cervical os
which part of the uterus is considered the lower uterine segment?
part of the uterus below the vesicouterine fold of peritoneum (need to open it and push down the bladder to visualise LUS in C-sections)
what is the clinical presentation of placenta praevia?
Placenta praevia presents with bright red, painless, recurrent vaginal bleeding occurring usually near the end of the 2nd trimester (or later):
• Sentinel bleed (first bleeding) is rarely so profuse as to cause death (ceases → recurs)
• Foetal movements and condition are normal
• Other clinical features (eluding to PP): high presenting part, abnormal foetal lie
what is the gold standard for diagnosis of placenta praevia?
The gold standard for diagnosis is transvaginal ultrasound (TVUS), which is safer and more accurate than transabdominal ultrasound in locating the placenta.
what is placenta accreta?
Penetrates through
decidua basalis
what is placenta increta?
Penetrates through myometrium
what is placenta percreta?
Penetrates through serosa (surrounding uterus)
Placental abruption refers to premature separation of a normally sited placenta from the uterine wall → clinical diagnosis:
• Usually associated with constant severe abdominal pain (whereas placenta praevia tends to be painless) → due to infiltration of blood into the ____________
o Features: vaginal bleeding, pain, uterine tenderness & irritability, foetal distress/death, evidence of DIC
• Ultrasound is usually requested to confirm ____________ and exclude ___________
myometrium;
foetal viability;
praevia
Vasa praevia occurs when the foetal vessels traverse the foetal membranes over the ____________ (below the foetal presenting part) → affects ~1 in 1000 pregnancies:
• Associated with _____________ (vessels run between the main lobe and accessory placental lobe → may rupture when membranes rupture)
• No risk to the mother; significant risk to foetus (50% mortality risk) → unprotected foetal vessels are disrupted when membranes rupture → foetal/APH → foetal distress
internal os;
velamentous cord insertion
Uterine rupture is a rare but very dangerous condition for both mother and baby, where the uterine wall spontaneously tears and may expel the foetus into the peritoneal cavity:
• Associated with previous uterine surgery (C-sections, myomectomy, D & C if cavity has been breached)
o May occur with no previous uterine surgery when _____________ (to increase intensity and frequency of contractions) is used inappropriately
• Other risk factors: trauma, grand multiparity (> 5 pregnancies before), excessive oxytocin use, ___________ (obstruction in labour), high forceps delivery
oxytocin infusion;
shoulder dystocia
what is the clinical presentation of uterine rupture?
- Pain over site of uterine scar, vaginal bleeding
- Disruption of labour: Abnormal cardiotocograph (CTG) → abnormal foetal heartbeat and/or uterine contractions, cessation of uterine contractions, inability to feel the foetal presenting part in the pelvis
- Hypovolaemic shock: Hypotension, tachycardia, pallor
- Haematuria (if rupture involves bladder → bleeding into urine)
Show is a sign of the early stage of labour where the ________________ (which seals off the cervix and uterus during pregnancy) is expelled due to cervical dilatation:
• May be associated with bleeding (bloody show) → ________________ mucus
• Common harmless cause of bleeding in late pregnancy → careful evaluation is required to exclude other pathological causes of APH (e.g. placental abruption)
cervical mucus plug;
blood-tinged
Cervical ectropion (ectopy/erosion) occurs when the ____________ exposes the ________________ to the vaginal milieu:
• Common normal finding in pregnancy → exposed columnar epithelium is prone to light bleeding when touched (e.g. coitus, speculum insertion, bimanual examination, cervical specimen obtained for cytology/culture)
• Therapy is usually unnecessary
eversion of the endocervix;
columnar epithelium
what are cervical causes of bleeding?
- cervical ectropion
- cervical polyp
- cervicitis
- cervical cancer
