My daughter is 13 and still sees her pediatrician. At what age is it appropriate for her to begin seeing an OB/GYN for her primary care?

The American College of Obstetricians and Gynecologists (ACOG) recommends regular Pap smears starting at age 18. I recommend age 18 or thinking about sex, whichever comes first. If a young woman is contemplating becoming sexually active, then I think she should be armed with as much information as possible before the fact. Seeing a gynecologist is a wonderful opportunity to discuss the implications of sexual activity, to ascertain that she is not being pressured into having sex, and to boost her self-image so that she is not saying "yes" just because of peer pressure. A gynecological visit is also a good time to discuss the pros and cons of different contraceptive options and to remind her to always use a condom if she chooses to have sex.
At age 13, if your daughter is not sexually active and she is not having any problems with her periods, she can wait. If she begins to have problems such as heavy bleeding, irregular cycles or bad cramps, she should see a gynecologist.