A Woman Who Is 4 Weeks Pregnant Is Worried That

A woman who is 4 weeks pregnant is worried that a medication she took until 3 weeks ago may cause birth defects. The nurse will tell her that:

A) drugs taken in the first week of pregnancy can cause CNS defects.
B) medications have increased teratogenicity during the first week of pregnancy.
C) she should have an ultrasound immediately.
D) teratogenic effects are rare in the first 2 weeks of pregnancy.