Normal and abnormal Uterine Artery
1.With lateralized placenta you will see lower RI and PI on the ipsilateral Uterine A.
2.With uterine contraction during labor blood supply is reduced leading to increased Doppler indices
normal
RI- 0.5
& PI- 0.8
First half of pregnancy shows physiologic notch in early diastole
Early diastolic notch in uterine should disappear by 25 weeks of pregnancy
This early diastolic notch should disappear by 25th week of gestation. If it persists on both sides even after 25 weeks is abnormal and associated with increased risk of pre-eclampsia ,placental abruption ,PIH & IUGR.
Rx: If there is a prior history of HT,Pre-eclamptia,placental insufficiency ) aspirin 70 to 100mg /day should be started from 14 weeks.
Image?
Significant placental insufficiency ,post systolic notch may be accompnied by a second, intrasystolic notch. This is a bad prognostic sign.
Normal and abnormal Umbilical Artery
There are two umbilical arteries,
Single umbilical Art (SUA) associated with chromosomal abnormalities,malformation,premature death and mortality.
Short cord syndrome is a serious a grave prognosis(normal is 50 cm).It could be short or absent , may be associated with absence of fetal ventral abdominal wall.
Coiling of cord around neck -generally harmless (seen in 50% births)
Diastolic flow not seen in first 10 weeks, how ever it increases steadily as the pregnancy progresses and can be seen by 15th week.waveform is affected by fetal respiratory and body movements.
Because of low resistance in uterop-lacental circulation RI & PI are lower on placental side than fetal.
Normal RI and PI -Image?
