Miscarriage

Question 1

What is the definition of miscarriage?
How common is it?
When is the most common gestation for dx?

Answer 1

Spontaneous loss of intrauterine pregnancy before 20 weeks gestation.
10-20% of clinical pregnancies result in miscarriage (40% at age 40)
80% will occur within 8-12 weeks gestation

Question 2

What are the most common causes?

Answer 2

Chromosomal abnormality (60%)
age
uterine abnormalities
incompetent cervix
thrombophilias/immunological
Infections
Toxins

Question 3

What are the different types of miscarriage?

Answer 3

Threatened - vaginal spotting or light bleeding, minimal pain, cervical os closed, USS live intrauterine fetus
Incomplete - increased bleeding, pain, cervical os open +/- products seen
Complete - products passed, cervix closed
Septic - fever, bleeding, tenderness and pain
Missed/delayed - absence of embryonic or fetal (>9 weeks) heartbeat

Question 4

How should threatened miscarriage be managed?

Answer 4

1) Dx will usually be clear from hx, examination (stable, abdo soft, speculum - cervix closed, small blood only), urine pregnancy test.
2) TV USS to confirm viable intrauterine pregnancy
3) Reassure woman, advise ?50% risk of miscarriage. Advise that we don’t have any proven treatment - most women prefer to rest and avoid intercourse until bleeding stops. Advise to take paracetamol as required, and return if bleeding becomes heavy, pain worsens or she is concerned.

Question 5

How should the haemodynamically unstable, incomplete miscarriage patient be managed?

Answer 5

1) Recognise emergency and need for resuscitation - call for help from gynaecology reg, nursing staff, anaesthetics and inform OT
2) IV access - 2 wide bore cannulae, send bloods for FBC, Gp and cross match 2 units
3) Give fluids and analgesia - IV N/S 1L stat plus morphine
4) Stop the bleeding - remove products from os with sponge forceps, give oxytocic syntocinon +/- ergometrine
5) Arrange for theatre for suction evacuation of the uterus - explain and obtain patient consent - risks are perforation, tears, haemorrhage, infection and intrauterine adhesions.
6) Give anti-D Ig to Rh-neg women - 250 for 12 weeks
7) Follow-up - provide counselling to patient
8) Follow-up histology to exclude gestational trophoblastic disease

Question 6

What is the role of expectant and medical management of miscarriage?

Answer 6

Expectant - stable patient who prefers this option - must have follow-up 7-10 days

Medical - stable patient who prefers this option - misoprostol with specific patient consent. 800 microg Day 1 (and 2 if not complete)
Review at 48 hours and Day 8 - consider surgical mx from 48 hours if not complete or by Day 8.
Perform FBC, B hCG and USS
Bleeding may continue for 2-3 weeks post tx
Medical review 6 weeks post first dose, avoid pregnancy for 4 months post dose?

Question 7

When should you investigate for cause of miscarriages?

Answer 7

Women with recurrent (2 or more) miscarriages under 12 weeks, or a 2nd trimester pregnancy loss, should be referred.
After 1 miscarriage, risk of recurrence is same as general
After 2, risk is 25%
After 3, risk is 40%
Investigations look for underlying thrombophilia, medical disorders or chromosome structure abnormalities - parental karyotyping or cytogenic analysis of 3rd m/c tissue.