20. Dating of pregnancy
Accuracy of dating- When biological variability is
minimal:
CRL is more accurate than BPD
But can be the most difficult measurement to
obtain
Dependant on operator
21.
22. Dating of pregnancy
Eg: between 5-7 weeks can be inaccurate
Full length of embryo not obtained
End points not separate from yolk sac or not included
From 9w: any flexion- can underestimate
25. Nuchal translucency
Between 11-14w
For chromosomal abnormalities-principally trisomy 21
An increased collection of subcutaneous fluid (NT) behind the neck
Structural abnormalities, genetic cond, cardiac abnormalities
Numerical cut off in relation to gestational age
Adjusted to maternal age, CRL and NT
27. Problems of early pregnancy
Miscarriage
Ectopic pregnancy
Abdominal pregnancy
Trophoblastic disease
Ovarian probs in early pregnancy
Uterine fibroids
Pregnancy with IUCD
28. Problems of early pregnancy
Hormonal measurement (HCG)
Monoclonal antibody based UPT can detect >25 iu/L = 2425/7 of a normal 28/7 cycle (i.e before one misses the
period)
Serum HCG doubles every 2/7
Combine w USS: no intrauterine preg, no doubling Of HCG
in 2-3/7, or cut off point of 1000iu/L
30. Problems of early pregnancy
Threatened miscarriage :
PV bleed with live embryo
15% proceed to miscarriage
Subchorionic haematoma # poor outcome
31. Problems of early pregnancy
Missed miscarriage:
Early featal death but retained GS
RCOG: absence of cardiac activity when CRL > 6mm
Absence of yolk sac or embryo when CTS > 20mm
If less than above, repeat after 1/52
37. Problems of early pregnancy
Ectopic pregnancy:
Implantation outside uterine cavity:93% tubal
Incidence around 1%
Presentation: classical, abd pain with PV
bleeding, silent
38. Problems of early pregnancy
Ectopic pregnancy:
Ultrasound findings:
UPT positive with empty uterus
With vaginal probe 85% can be visualised
Pseudo sac--> 10-30% of ectopic
Presence of fluid in POD--> 20-25% of ectopic
39. Problems of early pregnancy
Trophoblastic disease:
Spectrum: benign- hydatidifom mole, malignantchoriocarcinoma
Complete hydatidifom mole- snow storm appearance, no
fetal tissue, serum HCG high
Partial hydatidifom mole- trophoblastic hyperplasia w
fetal tissue
40. Problems of early pregnancy
Ovarian:
Mostly corpus luteum cyst- resolves <12w, usually < 5mm,
single but can be complex
Theca lutein cyst
Dermoid cyst
Benign cystadenoma
Endometriomas