Third Trimester Bleeding

Question 1

What is placenta praevia?

Answer 1

Placenta partly or wholly inserted into lower uterine segment, sometimes covering the cervical os

0.5% of pregnancies
3% with low lying placenta on USS scan continue to term

Question 2

Types of placenta praevia

Answer 2

Major (III & IV) - Cover the os

Minor (I & II) - Lies in lower segment, close to or encroaching on the os

Question 3

How does placental praevia present?

Answer 3

Painless vaginal or post coital bleeding

Question 4

Management of PP

Answer 4

Women who have bled previously and have major PP should be admitted from 34 weeks

Asymptomatic can remain at home if: close to the hospital, constant companion, fully aware of risks and has phone and transport

Delivery will be CS if placental edge is <2cm from internal os (posterior, thick)

Question 5

Common causes of third trimester abdominal pain?

Answer 5

Preterm labour
Braxton Hicks contractions
Placental abruption - separation of placenta and retroplacental bleeding
Chorioamnionitis - although pre-labour rupture of rupture usually precedes, infection may be present without rupture and cause abdo pain
Uterine torsion

Question 6

How do you diagnose preterm labour?

Answer 6

Fetal fibronectin

Presence of contractions

Question 7

Management of preterm labour

Answer 7

Corticosteroids to induce fetal lung maturity
- betamethasone 12mg 2 doses, 24 hours apart

Tocolytics - nifedipine (cc blocker), atosiban (oxytocin antagonist), indomethacin (cox inhibitor, acts as anti-prostaglandin
Used to allow time for steroids to take effect

Magnesium sulphate

Question 8

Signs and symptoms of placental abruption

Answer 8

Bleeding
Abdo pain
Uterine tenderness

Vaginal bleeding fetal compromise
Maternal shock
Coagulopathy

Question 9

What is couvelaire uterus?

Answer 9

Placental abruption causes bleeding that penetrates into myometrium forcing its way into the peritoneal cavity

Question 10

Signs of uterine rupture

Answer 10

Abdo pain
Hypovolaemia
CTG abnormalities 
Uterine contractions may stop
Palpation of fetus outside uterus

Question 11

What is primary arrest?

Answer 11

Failure of the cervix to dilate by 2cm in 4 hours

OR

slowing of progress for multiparous women

Question 12

What is secondary arrest of labour?

Answer 12

Cessation of cervical dilation following a normal portion of active phase dilation

Question 13

Types of episiotomy

Answer 13

Midline - vertical cut from fourchette towards the anus (higher incidence of 3rd and 4th ° tears, less bleeding, less pain, better healing, easier to repair

Mediolateral episiotomy - starts in midline in the fourchetter and is directed laterally to avoid anus

Question 14

Perineal tears

Answer 14

First-degree - skin only

Second-degree - involves perineal muscles (most common)

Third-degree - perineal tear leading to partial or complete disruption of the anal sphincter

Fourth-degree - the same as third-degree but involving the anal epithelium

Question 15

Risk factors for placenta praevia

Answer 15

Previous C sections
Previous termination
Multiparity
Advanced maternal age
Smoking
Deficient endometrium (uterine scar, endometritis, curettage, submucous fibroid)
Assisted conception

Question 16

What is valementous cord insertion?

Answer 16

Umbilical vessels go with the membranes before insertion

Risk of damage at membrane rupture causing fetal haemorrhage (also from succenturiata) - vasa praevia (60% mortality)

Question 17

Causes of PPH

Answer 17

Primary - vaginal trauma, uterine atony, placental (retained products, accreta)

Secondary - retained products, infection, dysfunctional uterine bleeding