Early pregnancy - First trimester USS Flashcards
What is the first structure to be seen on TVUS? When can it be seen on TVUS and Abdo USS?
Gestation sac
TVUS 31days/4+3
Abdo US 5+3
When should the yolk sac become visable on TVUS?
5+1-5+5
When mean sac >12mm
No detectable after 12 weeks
When should the embryonic pole be visible? When is cardiac pulsation seen?
5+2-6+0
Mean sac diameter >18mm
Embryonic pole 2-4mm cardiac pulsation is sen
In multiple pregnancy, how should gestation age be determined?
Using CRL of larger baby
All viable embryos should show cardiac activity by which CRL?
7mm
If TVUS CRL<7mm and no FH seen, what should happen?
Repeat USS in >7 days
If TVUS CRL >7mm and no FH, what should happen?
Seek 2nd opinion or
repeat USS >7days
If no FH on TAUS
Record CRL
Repeat USS in 14 days
What is the mm cut off for mean sac diameter and visible fetal pole?
25mm
Same rules as above for FH and CRL 7mm
What should be consider before Dx complete miscarriage on USS?
Is this PUL/ectopic
Offer hCG levels or repeat USS until definitive Dx made
Based on LMP what is the EDD?
280 days after LMP
Until what gestation can CRL be used to date the pregnancy? What is the accuracy
13+6 weeks (<84mm)
+/- 5-7 days
How is 2nd trimester EDD calculated?
BPD, HC, FL, AC
Less accurate +/-7-14 days
Accuracy of dating pregnancy > 28 weeks?
+/- 21-30 days
Risk re-dating small foetus
What to advise women with confirmed intrauterine pregnancy who presents with vaginal bleeding but no previous Hx of miscarriage?
- If bleeding gets worse, or persists >14 days, return for assessment
- If bleeding stops, become routine AN care
What to advise women with confirmed intrauterine pregnancy who presents with vaginal bleeding but has previous Hx of miscarriage?
Offer vaginal progesterone 400mg BD until 16 weeks
Expectant mgmt of miscarriage for 7-14 days is 1st line, other than:
- Increased risk haemorrhage (late 1st trimester)
- Previous adverse/traumatic experience (stillbirth, miscarriage, APH)
- Increased risk of effects haemorrhage (refuses blood, coagulopathy)
- evidence of infection
Follow up for expectant management of miscarriage
If resolution of pain & bleeding within 7-14 days, repeat UPT 3 weeks
Offer repeat USS if
- Pain/bleeding not started
- Persisting or increasing
What dosed of misoprostol should be given for medical mgmt of missed miscarriage?
800mcg, should contact if no bleeding with 24 hours
What dosed of misoprostol should be given for medical mgmt of missed miscarriage?
600
What other medications should be given for medical mgmt miscarriage
Analgesia
Anti-emetic - can have diarrhoea and vomiting
What FU for medical mgmt
Repeat UPT in 3 weeks
Risk of significant complications from ERPC?
6%
How long can bleeding occur after ERPC? Risk of heavy bleeding needing transfusion?
2 weeks
0-3/1000
Risk of pelvic infection following ERPC
4/100 4% (common)
Risk of retained tissue following ERPC?
4/100 4%
Risk of uterine perforation in ERPC?
1 in 1000
(More common after surgical TOP or increased gestation)
Most common sites for uterine perforation at ERPC?
Anterior wall 40%
Cervical canal 36%
What instrument is most likely to cause perforation?
Suction cannula 50%
Hegar dilator 25%
Curette 15%
Mgmt of perforation
If small (dilator or curette) likely conservative mgmt if patient stable
If larger diameter e.g. suction Dx Lap
Risk of intrauterine adhesions for any type of management of miscarriage?
19%
No difference in fertility outcomes between the different management options.
