The distribution of reviewer estimated pregnancy start difference in days from the algorithm start (< -14, -8 thru -14, -1 thru -7, 0, 1 through 7, 8 through 14 and > 14 days) in the Optum database, stratified by pregnancy outcome (all outcomes, live birth, abortion, ectopic pregnancy, and stillbirth) and method used for pregnancy start estimation.

<p>Legend for start estimation methods referenced in row panels:</p> <p>LMP = last menstrual period</p> <p>GEST = gestational age record</p> <p>INFERT = fertility procedure</p> <p>ULS = nuchal ultrasound</p> <p>AFP = alpha-fetoprotein test</p> <p>AMEN = amenorrhea record</p> <p>URINE = urine pregnancy record</p> <p>AVG = average gestational age estimate</p> <p>ALL = all start estimation methods combined</p> <p>*If percentages do not add up to 100%, reviewer indicated difference in days from the algorithm could not be determined.