[Predicting the risk of poor pregnancy outcome by ultrasound examination of yolk sac diameter].

Ultrasound examination with 7.0 MHz transvaginal transducer was performed in 136 pregnant women between 5 and 12 weeks of pregnancy. Yolk Sac diameter and Crown-Rump Length were measured. It was observed that absence of YS or its diameter greater than 7 mm was usually associated with poor pregnancy outcome.