I'm now in the 1ww and we are still BD'ing just in case. I think I know the signs of when I'm ov'ing and I had them last Saturday and I've been charting and my temp rose on Monday so I think that's right. I'm not sure if there is any way to know for sure so I don't see the harm in keep trying in the 2ww. If you do a search on google, you'll see that quite a few ppl have got pregnant on the day before their period. Some ppl even get pregnant during their period. I don't know how they would know this though as if I was pregnant this month, I wouldn't know when it happened (unless they only had sex once that month).