Does she have fleas? I would not bother with a capstar if she does not. I use Frontline on my dogs normally, but while my bitch was pregnant and nursing, I did not re apply. I did not put it back on her until my pup was old enough to get his first dose (8 weeks I believe is on label.) It does say that it is safe for pregnant/lactating bitches... But I did not want to chance it. I had a lot of trouble getting her pregnant, so I was taking no unneeded risks.