Q&A: Dry Vagina During Sex – What Can I Do?

My girlfriend’s vagina gets very dry during intercourse. I have to use a lot of lubricant in order to have sex with her and then it get dries again after 10 minutes. She is not taking any medication or birth pill. Sometime it is so dry that it damages the condom. In foreplay she is wet for a few minutes, but then she gets dry when we have sex.