Jill Duggar and Derick Dillard are preparing to become parents. The couple who was just married last June is now expecting another addition to their family. According to E! Online, the "19 Kids and Counting" star's pregnancy raises questions if they did or did not remain sexually "pure" before their marriage. Is the baby conceived before tying the knot?

The online publication reported that speculation began because Jill, and her husband Derick announced that they are expecting their first child more than two months after their nuptials last June 21. Reportedly, on September 17, Jill posted a photo in her Instagram account showing that she was 13 weeks and 1 day pregnant or 93 days. At that time, counting back to their wedding day, it was 90 days.

Base on the numbers presented it can be assumed that the couple who are practising "conservative and traditional" beliefs engaged in pre-marital sex. But according to justmommies.com, that's not the way we calculate for the conception.

"Doctors count the length of a pregnancy as 280 days, which equals 40 weeks or 10 months. Why not nine months? The counting begins with the first day of your last normal menstrual period before you got pregnant. In other words, the counting begins about two weeks before you have even conceived," justmommies.com stated.

"Many women assume that the date of conception is the same date that they had intercourse. However, since sperm can live inside your body for as long as five days, conception could happen up to five days after intercourse, depending on when ovulation occurred," the online site expounded.

Christian Post recently reported that Jill, who is now on her second trimester, chose to give birth at home. Examiner noted that the home where she'll have the baby is the first house that they have shared together as a married couple.