Bleeding in first trimester

Question 1

Bleeding in first trimester:

how common is it?

Answer 1

20% - 40% of pregnancies

What it actually happens:

• ≤20% = miscarriage
• ≤2% ectopic prenancy

Question 2

Bleeding in first trimester:

Approach?

Answer 2

History:

• Last menstrual period to calculate gestation estimate
• timing, frequency, volume of blood loss
• any associated symptoms

LMP 
-3months
\+1 year
\+ 7 days
= EDD

• long cycles add the difference
• short cycles subtract the difference

Examination:

• BP and HR - check postural changes concerning for ectopic rupture
• abdomen (check for a fundus present - generally not palpable until after 12/40)
• speculum (remove products of conception if any in Os as untreated they can cause shock - send for histopathology, may choose to do a high vaginal swab if indicated)

Question 3

Bleeding in first trimester:

How to investigate?

Answer 3

urine beta hcG AND vaginal bleeding = Trans vaginal Ultrasound

Questions needing answering:

• where is the embryo located
• is it viable
• how to plan follow up

1) Intrauterine gestational sac (GS)
a) Foetal Pole (FP) present
i) AND foetal heart rate (HR) = viable
ii) AND no HR
I) If crown rump length (CRL) >7mm = missed
miscarriage
II) CRL < 7mm = too early REPEAT USS in 7 days

b) No FP
i) AND GS >25mm = missed miscarriage
ii) AND GS <25mm = too early REPEAT USS in 7
days

2) No intrauterine GS
a) GS extrauterine = ectopic

b) Products of conception (POC)
i) Nil = UNKNOWN PREGNANCY LOCATION
ii) Nil AND past intrauterine gestational sac
seen on USS = complete miscarriage
iii) POC intrauterine = incomplete miscarriage

UNKNOWN PREGNANCY LOCATION

1) Repeat beta hcG in 48hrs post last
2) calculate the percentage change
a) ≥63% rise = likely viable intrauterine pregnancy
* if beta hcG >1500 should be able to see GS on USS
* 21% of ectopic pregnancies meet this criteria

b) ≥50% fall = non viable
* repeat beta hcG in 14 days and monitor symptoms

c) If does not meet a) or b) = specialist review

Question 4

Bleeding in first trimester:

Management of expected misscariage?

Answer 4

Expected miscarriage can be managed expectantly and should complete passage of POC by 2 - 4 weeks

1) missed 76% chance
2) incomplete 91% chance

The women may prefer to have procedural intervention via women’s health clinic or private specialist.

Question 5

Bleeding in first trimester:

Management of ectopic pregnancy?

Answer 5

1) Medical - typically methotrexate is used
2) Surgical

Depends on the contraindications as to which is reasonable.

If medical is being considered then ensure there is :
-quantitative beta hcG
-CBE
-LFTs
-EUC
AND if RH negative they will require anti-D administration