2011-3-25

解析：Sentiments are even more negative among the group [ that might place the highest value on being able to escape an unwanted pregnancy]: young people.
结构:  方括号标示的是group的后置定语.冒号后面的名字短语是补充说明the group.
翻译：年轻人本应对解脱意外怀孕的手段最重视，然后，这个群体却对堕胎持更加消极的态度。