The experience during actual intercourse will be the same as you would expect with any first penetration. She may experience pain, especially if her hymen is intact, a burning sensation, and blood (this varies in amount, and is usually bright red). You may find difficulty penetrating. After intercourse the bleeding should stop flowing within the hour, but she may spot for days. She will probably have some irritation, and swelling, but she should not douche or use any feminine hygiene products except gentle soap and water.
Be extremely gentle, and prepared to go slowly and/or stop if necessary. If a lubricant is necessary, be sure to use only a water based natural lubricant such as KY Jelly.
If her celibacy is due to factors other than personal choice or circumstances, she may have some special emotional needs to be addressed before and after her first experience.
She should absolutly see the Doctor before the wedding for a full exam, and pap smear. She should then see him yearly thereafter.
Remember birth control is necessary, even with the first experience, unless her menstruation has ceased completely.
Best of luck to you both.
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