Early pregnancy - First trimester USS

Question 1

What is the first structure to be seen on TVUS? When can it be seen on TVUS and Abdo USS?

Answer 1

Gestation sac
TVUS 31days/4+3
Abdo US 5+3

Question 2

When should the yolk sac become visable on TVUS?

Answer 2

5+1-5+5
When mean sac >12mm

No detectable after 12 weeks

Question 3

When should the embryonic pole be visible? When is cardiac pulsation seen?

Answer 3

5+2-6+0
Mean sac diameter >18mm
Embryonic pole 2-4mm cardiac pulsation is sen

Question 4

In multiple pregnancy, how should gestation age be determined?

Answer 4

Using CRL of larger baby

Question 5

All viable embryos should show cardiac activity by which CRL?

Answer 5

7mm

Question 6

If TVUS CRL<7mm and no FH seen, what should happen?

Answer 6

Repeat USS in >7 days

Question 7

If TVUS CRL >7mm and no FH, what should happen?

Answer 7

Seek 2nd opinion or
repeat USS >7days

Question 8

If no FH on TAUS

Answer 8

Record CRL
Repeat USS in 14 days

Question 9

What is the mm cut off for mean sac diameter and visible fetal pole?

Answer 9

25mm
Same rules as above for FH and CRL 7mm

Question 10

What should be consider before Dx complete miscarriage on USS?

Answer 10

Is this PUL/ectopic

Offer hCG levels or repeat USS until definitive Dx made

Question 11

Based on LMP what is the EDD?

Answer 11

280 days after LMP

Question 12

Until what gestation can CRL be used to date the pregnancy? What is the accuracy

Answer 12

13+6 weeks (<84mm)
+/- 5-7 days

Question 13

How is 2nd trimester EDD calculated?

Answer 13

BPD, HC, FL, AC

Less accurate +/-7-14 days

Question 14

Accuracy of dating pregnancy > 28 weeks?

Answer 14

+/- 21-30 days
Risk re-dating small foetus

Question 15

What to advise women with confirmed intrauterine pregnancy who presents with vaginal bleeding but no previous Hx of miscarriage?

Answer 15

• If bleeding gets worse, or persists >14 days, return for assessment
• If bleeding stops, become routine AN care

Question 16

What to advise women with confirmed intrauterine pregnancy who presents with vaginal bleeding but has previous Hx of miscarriage?

Answer 16

Offer vaginal progesterone 400mg BD until 16 weeks

Question 17

Expectant mgmt of miscarriage for 7-14 days is 1st line, other than:

Answer 17

1. Increased risk haemorrhage (late 1st trimester)
2. Previous adverse/traumatic experience (stillbirth, miscarriage, APH)
3. Increased risk of effects haemorrhage (refuses blood, coagulopathy)
4. evidence of infection

Question 18

Follow up for expectant management of miscarriage

Answer 18

If resolution of pain & bleeding within 7-14 days, repeat UPT 3 weeks

Offer repeat USS if
- Pain/bleeding not started
- Persisting or increasing

Question 19

What dosed of misoprostol should be given for medical mgmt of missed miscarriage?

Answer 19

800mcg, should contact if no bleeding with 24 hours

Question 20

What dosed of misoprostol should be given for medical mgmt of missed miscarriage?

Answer 20

600

Question 21

What other medications should be given for medical mgmt miscarriage

Answer 21

Analgesia
Anti-emetic - can have diarrhoea and vomiting

Question 22

What FU for medical mgmt

Answer 22

Repeat UPT in 3 weeks

Question 23

Risk of significant complications from ERPC?

Answer 23

6%

Question 24

How long can bleeding occur after ERPC? Risk of heavy bleeding needing transfusion?

Answer 24

2 weeks
0-3/1000

Question 25

Risk of pelvic infection following ERPC

Answer 25

4/100 4% (common)

Question 26

Risk of retained tissue following ERPC?

Answer 26

4/100 4%

Question 27

Risk of uterine perforation in ERPC?

Answer 27

1 in 1000
(More common after surgical TOP or increased gestation)

Question 28

Most common sites for uterine perforation at ERPC?

Answer 28

Anterior wall 40%
Cervical canal 36%

Question 29

What instrument is most likely to cause perforation?

Answer 29

Suction cannula 50%
Hegar dilator 25%
Curette 15%

Question 30

Mgmt of perforation

Answer 30

If small (dilator or curette) likely conservative mgmt if patient stable
If larger diameter e.g. suction Dx Lap

Question 31

Risk of intrauterine adhesions for any type of management of miscarriage?

Answer 31

19%
No difference in fertility outcomes between the different management options.