“…Reviewing our own cases with TRAP sequence and reviewing the literature of the past 20 years, we come up with an 11% figure. The anomalies reported in the co-twins are tetralogy of Fallot, single ventricle, aortic arch anomalies, patent ductus arteriosus, anencephaly with rachischisis, exomphalos, micrognathia and low set ears, Vater association, brain abnormalities, renal abnormalities, and chromosomal abnormalities [Onyskoswova et al, 1970;Renziehausen et al, 1973;Benirschke and Des Roches Harper, 1977;Vangen 1977;Barr et al, 1978;Harkavy et al, 1978;Neilson et al, 1982;Gewolb et al, 1983;Pavone et al, 1985;Van Groeninghen et al, 1985;Beuhler et al, 1986;Bhatnagar et al, 1986;Hall, 1986;Mulhaus and Beisler, 1986;Reuhland et al, 1986;Moore et al, 19871. It is often not possible to give accurate data on acardiac amorphous twins and their co-twins due to incompletely reported cases [Bhatnagar et al, 1986;Schulze et al, 19851.…”