Most often, when the woman is not properly aroused (lubricated) and if the man makes an attempt to enter, it leads to irritation and pain at the time of intercourse. If the pain is always present at the time of intercourse then it could be because of hymenal obstruction, urethral disorders or congenital malformation of the vulva or vagina. It could also occur following post-operative scars and atrophic vulvo-vaginitis (common in menopausal years). If the pain is present occasionally, then one may look for some local infection and/or allergy.