*    Department of Gynecology, Félix Guyon Hospital, 97400 Saint-Denis, Ile de la Réunion, France. Tel: 0262 90 55 22, Fax: 0262 90 77 30;
**   Gynecologist, Sainte-Clothilde Clinic, 97400 Saint-Denis, Ile de la Réunion, France;
***  Sonographer, Moufia Street, 97400 Saint-Denis, Ile de la Réunion, France;
**** Sonographer, Translator, Editor, Novato, California. Email: timbre440@yahoo.com.
We present the case of a 30-year-old woman scanned at 13 weeks GA after in vitro fertilization. Her medical history was noncontributive. We found a dichorionic pregnancy. Fetus A (closer to the internal os) had a normal nuchal translucency (1 mm). Fetus B presented with acrania and encephalocele. The nuchal translucency of fetus B was 4 mm. The parents chose selective interruption of pregnancy.
Figures 1, 2 - Twin pregnancy at 13 weeks GA with one normal skull and one acrania