Supplementary Material for: Prenatal Diagnosis of a Spontaneous Monochorionic Five-Amniotic Quintuplet Pregnancy

<i>Objectives:</i> It is the aim of this study to report on the prenatal diagnosis and course of a spontaneous monochorionic (MC) 5-amniotic (5A) quintuplet pregnancy which is such a rare event that it has up to now never been described antenatally. <i>Case Report:</i> A spontaneous MC 5A quintuplet pregnancy was diagnosed at 12 weeks by 2D ultrasound. Video tapes (2D and 4D) were made showing that 2D ultrasound still better documented simultaneous visualization of all quintuplets including their activities compared with 4D ultrasound, which, however, adds the information of space location. Variances of crown-rump length, nuchal translucency and nasal bone were evaluated. After informed consent and a second opinion of 2 centers performing invasive laser coagulation or occlusion of the umbilical cord, the parents decided to interrupt pregnancy. Pathologic evaluation confirmed MC 5A quintuplet pregnancy. <i>Conclusion:</i> The case demonstrates that splitting of 1 zygote into 5 embryos might even occur spontaneously. In view of the poor outcome and limited success of fetal reduction, pregnancy termination was finally part of the counseling.