pregnant, they're recommending to use some form of birth control because it can cause fetal growth problems, and so definitely given where we are in the pandemic, it is great to have something that needs to be given orally by mouth at home. however, with this particular pill there are those precautions on it. >> some limitations for sure. israel this week became the first country to recommend a fourth dose of pfizer or a second booster essentially to some citizens. the president was asked if that's something that could happen here. let's listen. >> they're already moving forward with a second booster now, so this would be the fourth shot for people 60 and older and for front line medical workers. is that something you're considering? >> i listen to the scientists, and i'm sure the scientists are paying very close attention to that. there may be a need for another booster. that remains to be seen. >> so it remains a possibility. >> it remains a possibility.