This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Gynaecology & Obstetrics
Aneuploidy, is the most common genetic abnormality, accounting for up to 50% of clinical miscarriages. All are true about aneuploidy, EXCEPT: 
Select and explain. 
A. 30-40% of trisomy 21, fetus die between 12 weeks and 40 weeks, B. 50-60% of trisomy 18, fetus die between 12 weeks and 40 weeks, C. Occurrence of triploidy has no relation with the progression of mother's age, D. In previous pregnancy with trisomy 21 due to non disjunction, the risk in future pregnancy is .75% higher
B: 50-60% of trisomy 18, fetus die between 12 weeks and 40 weeks
Answer: B: 50-60% of trisomy 18, fetus die between 12 weeks and 40 weeks 
Explanation: Also known as Edwards syndrome,trisomy 18 has an overall frequency of 1 in 8000 newborns and is three to four times more common in females. As with other aneuploidies, its incidence is much higher in the first trimester, and 85 percent of fetuses die between 10 weeks and term. Ref: Cunningham F.G., Leveno K.J., Bloom S.L., Hauth J.C., Rouse D.J., Spong C.Y. (2010). Chapter 12. Genetics. In F.G. Cunningham, K.J. Leveno, S.L. Bloom, J.C. Hauth, D.J. Rouse, C.Y. Spong (Eds), Williams Obstetrics, 23e.