A recent study concluded that children born to mothers who take Prozac tend to have more birth

Question:

A recent study concluded that children born to mothers who take Prozac tend to have more birth defects than children born to mothers who do not take Prozac.
a. What do you think the null and alternative hypotheses were for this study?
b. If you were a spokesperson for Eli Lilly (the company that produces Prozac), how might you rebut the conclusions of this study?