Leonard and Jane Mention That They Do Not Have Intercourse

Leonard and Jane mention that they do not have intercourse since they learned that Jane is pregnant. They are concerned that such vigorous activity could cause a miscarriage. What does research suggest about their concern?

A) A somewhat higher rate of birth defects is associated with having intercourse during pregnancy.
B) Except in the first trimester, intercourse is permissible during pregnancy.
C) In the absence of a medical problem, intercourse may occur, as long as it is comfortable for both individuals.
D) Multiple pregnancies could result from intercourse during pregnancy, so condoms should be used.