Exam 3 - Third Trimester Bleeding Flashcards
Vaginal bleeding in late pregnancy (third trimester) is associated with what?
Placental abnormalities
What are examples of placental abnormalities that are associated with late pregnancy bleeding?
- Placental structure or size abnormalities
- Abnormal placement
- Abnormal attachment or premature detachment
What implications do placental abnormalities have on the mother and fetus?
- Can cause maternal or fetal bleeding
- Affect fetal growth and oxygenation
May require early delivery to prevent compromise to the fetus and maternal morbidity
What are small placentas associated with during pregnancy?
Intrauterine infection
What are large or edematous placentas associated with during pregnancy?
Diet, maternal diabetes, fetal high drops
What is velamentous cord insertion?
Example of structural placental abnormality
- Portion of umbilical cord is lifted off the placental surface
- Umbilical cord strings up and out –> looks like tree roots
What is a potential complication associated with velamentous cord insertion?
Leaves span of vessels exposed and vulnerable to rupture or tear from fetal moveemnt or traction during delivery
What is vasa previa?
Velamentous vessels precede the fetus or cross the cervix
- Fetal blood vessels cross the cervical opening resulting in life threatening hemorrhage at birth
What are risk factors for vasa previa?
- Velamentous cord insertion
- Low lying placenta
- Multilobar placenta
When should vasa previa be suspected on physical exam?
Suspected on vaginal exam when pulsations from cord are palpated
What is placenta previa?
Anterior or posterior developed placenta, extending to or across the cervical os
Malposition of placenta in lower uterine segment and extends across cervical os
Can placenta previa be detected on ultrasound?
Low lying placenta may be identified on ultrasound early in pregnancy (first or second trimester) when edge of placenta is 3 cm or less from cervical os
Complete previa
Body of placenta fills lower uterine segment entirely and overlay cervical os
Partial previa
Placental edge covers cervical os
Marginal previa
Edge of placenta is near but not actually covering internal cervical os
What is the cardinal sign of placenta previa?
Sudden onset painless vaginal bleeding
If a patient has a low lying or partial placenta previa, when should they follow up with ultrasound?
At 24-28 weeks
What happens if the placenta remains over the cervix by the third trimester?
Vaginal birth contraindicated
How would the provider manage placenta previa early in pregnancy?
Watchful waiting, no further intervention required
Management of complete previa
Pelvic rest for duration of pregnancy
- Avoid orgasm which can stimulate uterine contractions
What should patients do if they had been previously diagnosed with placenta previa and has vaginal bleeding?
Report to hospital immediately
- If bleeding subsides and mother and infant are stable, expectant management advised
Complications associated with placenta previa
- Hemorrhage and fetal demise when placenta separates before birth
- Associated with uterine scar from c-section or other uterine surgery
- Increased risk with repeat c-sections
What is abruptio placentae?
Premature separation of normally implanted placenta
What is the leading cause of hemorrhage in late pregnancy?
Abruptio placentae
Can bleeding from abruptio placentae be concealed?
Yes - blood accumulates behind placenta with no obvious bleeding
- Can penetrate through uterine decidua and collect in peritoneum
Risk factors for abruptio placentae
- Hypertensive disorder
- Previous abruption
- Maternal smoking and cocaine use
- Abdominal trauma
- Polyhydramnios
- Chorioamnionitis
Signs of abruptio placentae
- Early signs mimic labor: back or pelvic pain
- Blood discharge
- Tender abdomen to firm, rigid, board-like belly that is diffusely painful
