In the late 1960s, a number of pregnant women in Europe and Canada were prescribed a drug called thalidomide. Many of these women gave birth to children with amelia (no

In the late 1960s, a number of pregnant women in Europe and Canada were prescribed a drug called thalidomide. Many of these women gave birth to children with amelia (no limbs) or meromelia (malformed upper and/or lower limbs). It was later discovered that thalidomide is a teratogen that can cause limb defects in an unborn baby. Based upon this information, during what period of their pregnancy (pre-embryonic, embryonic, or fetal) do you think these women took thalidomide? During which of these periods would thalidomide cause the most harm to limb development?