It was never claimed by Jesus or any of his followers that He was the product of a virgin birth. This is one of the many claims of the Catholic church which conveniently for them cannot be proved or disproved. Therefore you either accept their word as infallible or be labeled as a heathen who is going to burn in hell when you die.
To further emphasize how divine and holy Jesus was, the church further claimed that Mary was the product of a virgin birth. The story goes that her parents were getting on in years without having produced any children. In Biblical times, girls were married at 12 to 14 years of again. When you reached your mid-twenties you were considered old, dried up and sterile. These elderly folks were probably in their 40s, just hitting their stride by today's standards.
But the claims go that Anna and Joachim were childless and labeled cursed by the local high priest for not having a son. Joachim went out to the fields to sulk. That's where an angel appeared unto him and announced his wife's impending pregnancy. Sound familiar? The story further states that the child will be from God, pure and holy, and must follow the strict Jewish laws for remaining pure. To ensure that God's instructions were obeyed, they took Mary to the temple when she was still a toddler and put her in a convent which she was kicked out of when she had her first period.
Christians consider the circumstances of her birth proof of how holy and miraculous Jesus is. Catholics take it a step further and use it as proof of her divinity. Historians and other doubters use it as proof that the circumstances around both births are complete works of fiction.
