A recent letter in the NEJM describes a noninvasive test to
determine paternity in pregnancy. (N Engl J Med 366; 18 May 3, 2012 page 1743.)
5% of raped women become pregnant, but whether the rape or consensual
intercourse caused the pregnancy is often uncertain. 80% of unintended
pregnancies are terminated before 10 weeks, making it likely many rape victims
terminate pregnancies before testing for paternity. The invasive tests carry a
risk of miscarriage, but here the authors report a maternal blood test that in correctly
determined paternity in all 30 cases studied.