There's usually some issue with this because there are some changes to the menstrual cycle. Birth control pills can correct it, but abortionists don't like using them. If the woman gives herself extra days just in case, it should decrease chances of pregnancy even more if they don't use the pills. It's just that some women are just whores that wouldn't be able to track it anyway or wouldn't add more days for precaution or they are abortionists looking to get pregnant so they can kill their children.

It doesn't help that women think this this is set and they have it under control and all the crap the NWO puts in food causes them to start early or late. Some of those women have some responsibility at first but it goes out the window once they start freaking out and the media tells them to have an abortion because "muh clump of cells".