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What doctors look at in 1st Trimester Ultrasound
-- Uterus and adnexa for presence of gestational sac
-- Presence or absence of yolk sac and/or embryo
-- Crown-Rump length of embryo if possible
-- Presence of cardiac activity
-- Fetal number and chorionicity/amnionicity
Reasons to have a 1st Trimester Ultrasound
-- Estimate gestational age
-- Diagnose or evaluate multiple gestations
-- Confirm cardiac activity
-- Confirm pressure of intrauterine pregnancy
-- Evaluate suspected ectopic pregnancy
-- Define cause of vaginal bleeding
-- Evaluate pelvic pain
What doctors look for in 2nd and 3rd Trimester Ultrasound
-- Fetal cardiac activity, number, and presentation
-- Qualitative or semi-quantitative estimate or amniotic fluid volume
-- Placenta location, appearance, and relationship to cervix
-- Gestational Age assessed using CRL, biparietal diameter, head circumference, femur length, and abdominal circumference
-- Fetal weight estimated using above measurements
-- Evaluation of maternal uterus and adnexal structures
