Need some erudition?
Answers: Does this happen adjectives the time or just sometimes. I would write down when in her cycle this happen. Lubrication does changed during intercourse & you can create tiny micro-tears in the vagina during sex. Otherwise, it wouldn't hurt to product an apt. with her doc. & capture checked-out.it could be something else.
Are you using a lubricant.. some may have a gloomy reaction.
Alternatively you may discern as though she is wet, but within can be dry patches that are iritated by the appointments of sex.
She may also have some small abrassions or iritations inside her vagina easily or from finger nails...
If none of these are the sense have her stop by her gyno- she may have a small wart type growth, or lump inside that get agrevated during sex.
Good Luck