OB Flashcards
recurrence risk vs baseline risk for fetal neural tube defect
3.2% recurrence risk with affected sibling vs 0.04% baseline risk
action of engagement cardinal movement
biparietal diameter enters pelvic inlet; leading edge of head is at or below station 0, fetal head enters pelvis transversely
action of flexion cardinal movement
fetal chin brought towards chest, shifting the occipitofrontal diameter of 12cm to a shorter suboccipitobregmatic diameter of 9.5cm
action of internal rotation cardinal movement
occiput moves toward pubic symphysis and away from a transverse axis, resulting in direct OA or OP
action of external rotation cardinal movement
aka restitution
occiput and fetal body rotate into transverse position, therefore rotating bisacromial diameter
what occurs during extension cardinal movement
delivery of fetal head
what occurs during expulsion cardinal movement
delivery of anterior and posterior shoulders
who is candidate for physical-exam indicated cerclage and when to place?
painless 1-4cm dilation
- place on dx during 2nd tri
who is candidate for US-indicated cerclage and when to place?
hx spontaneous birth <34wk & CL <25mm on US
- place at 16-24wk
who is candidate for hx-indicated cerclage and when to place?
clear hx cervical insufficiency (one or more 2nd-tri preg losses related to painless cervical dilation, prior cerclage for that reason)
- place 13-14wk
when is cardiac output highest in preg
increases throughout pregnancy, highest immediately postpartum
when can you change dating if LMP & US differ by more than 5 days
<9.0
when can you change dating if LMP & US differ by more than 7 days
9.0-15.6 (and lower)
when can you change dating if LMP & US differ by more than 10 days
16.0-21.6 (and lower)
when can you change dating if LMP & US differ by more than 14 days
22.0-27.6 (and lower)
