The Bible doesn't state that Elizabeth was a virgin when she became pregnant with her first. She and her husband Zacharias were each good before God. Their lifestyle stood God's test. They were made civic goodness' models. They walked in God's laws. In spite of their goodness, they were sad. No child had been given them. Childlessness was a disaster. Elizabeth was barren. God had denied her motherhood. At this time they were both old, beyond the days when they might expect children. They felt this childlessness as a rebuke. The barren were thought cursed. In Genesis 1, God said, "Multiply!" This the Jews urged. They that had no children weren't blessed. So a married couple without children must be cursed.Interesting to contemplate. So I guess Mary's elderly cousin Elizabeth - also pregnant with a first child concurrrent with Mary - would also have been considered a virgin.