Prospective study of parental choice for aneuploidy screening in assisted conception versus spontaneously conceived twins. 
The aim of this study was to evaluate and compare parental choice towards the use of aneuploidy screening and diagnostic techniques after assisted conception versus spontaneously conceived pregnancy.  A total of 193 patients with consecutive twin pregnancies participated in the study, including 143 who spontaneously conceived and 50 who conceived following assisted reproduction treatment.  Patients were investigated prospectively for their choice in the prenatal screening/diagnosis of aneuploidy.  In the group of patients who conceived spontaneously, 111 (77.6%) opted initially for the non-invasive screening based on nuchal translucency measurements, whereas in the assisted conception group, 44 (88%) opted for the non-invasive screening.  In the spontaneous conception group, 32 (22.4%) presented because they had a positive serum screening test or because they had opted for a chorionic villus sampling (CVS) or an amniocentesis for advanced maternal age.  In the assisted conception group only six patients (12%) opted for amniocentesis.  The difference in choice of noninvasive versus invasive screening between those with spontaneous and those with assisted conception was not significant, but those who had conceived spontaneously after the age of 37 years were significantly more likely (P < 0.05) to request an invasive diagnostic procedure through all maternal age groups.  When needed, an amniocentesis was preferred to CVS.  These data also indicate that the antenatal counselling needs to be adapted to couples presenting with an assisted conception twin pregnancy.