Wiktionary
n. 1 An individual who refrains from sexual activity, regardless of any past unchaste behavior. 2 A woman who undergoes a hymenorrhaphy to restore her hymen.
Wikipedia
A born-again virgin (also known as a secondary virgin or renewed virgin) is a person who, after having engaged in sexual intercourse, makes some type of commitment not to be sexually active again until marriage (or some other defined point in the future or indefinitely), whether for religious, moral, practical, or other reasons.
Usage examples of "born-again virgin".
Men like Bert were the reason she had spent the last four years as a born-again virgin.
If it hadn't been so long since I had a man in my bed, I'd even try that born-again virgin thingee of yers.
She also does a fine job of balancing the serious issues at the heart of her story with the more bizarre elements -- such as the party the Virtuous Woman throws for Florrie to celebrate the twentieth anniversary of her becoming a born-again virgin.