Ultrasonographic prediction of early miscarriage

The aim of this retrospective study was to assess the value of maternal history and ultrasound scan findings at 6-10 weeks for predicting early miscarriage.

Embryonic crown-rump length (CRL), heart rate (HR), gestational sac diameter (GSD) and yolk sac diameter (YSD) were compared in two groups of women with singleton pregnancies attending an early pregnancy unit. In the first group the initial scan demonstrated a live embryo but in a subsequent visit the scan showed a dead embryo, complete or incomplete miscarriage. In the second group with a live embryo there was subsequent live birth of a normal neonate.

There were 729 pregnancies with miscarriage and 4698 with normal outcome. Logistic regression analysis demonstrated that in the prediction of miscarriage the risk was higher in women of African racial origin [odds ratio (OR) 1.62], cigarette smokers (OR 1.91) and those with vaginal bleeding (OR 2.03) and increased with maternal age (OR 1.05) and YSD (OR 1.88) and was inversely related to CRL (OR 0.79), HR (OR 0.96) and GSD (OR 0.84). At false-positive rate of 30%, the detection rate of miscarriage in screening by vaginal bleeding was 45%, 53% by the addition of maternal history factors and 85.7% by the addition of ultrasound findings.

In early pregnancy a prediction of miscarriage can be provided by a combination of maternal characteristics and ultrasound findings and the estimated risk can be used to rationalize follow-up. Our multivariate model requires prospective evaluation in a new sample population.