Ultrasound observation of amnion dysmorphism at 14.5-16 weeks.

The presence of chorio-amniotic separation and amnion anomalies was recorded in 9500 patients referred for vaginal ultrasound examination at 14.5-16 weeks' gestation. In all patients with a change in the amnion, a search for fetal anomalies was performed and pregnancy outcome was checked. Amnion dysmorphism was observed in 30 cases. The main findings were a floating membrane which changed its configuration when the uterus was tilted and multiple intrauterine amniotic sheets. In no case was attachment of the fetus to the membranes noted. There was no fetal abnormality and pregnancy outcome was favourable in all patients. In conclusion, ultrasound visualization of amnion dysmorphism in early pregnancy is not associated with an adverse pregnancy outcome.