Hi Charlyfrog.

Here's a quick how it happens guide for people who don't like biology.

At 2w pregnant, you ovulate (one reason I liked the pre-O wait, I knew I was pregnant then, post-O I had to admit I wasn't) and the little eggies is charged at by the spermies. One little sperm infiltrates the egg and you've conceived! Well done!

For the next 7-12 days, the zygote (as the little tiny ball of cells that is your baby is called) travels down your fallopian tubes to your uterus. After that, it finds a nice safe place to snuggle into. Implantation can occur in the middle of an aerobics class (implantation is not the same as fertilisation - I really hope the latter wouldn't occur in an aerobics class!) so it is doubtful that extra BDing would shift it.

The zygote then starts to make a placenta, which in turn makes hCg (pregnancy hormone) and takes over your body. The zygote is now an embryo and is quite hard to shift. For example, when I was newly pregnant I was shifting huge bags of soil for our vegetable garden and plumbing in a new bathroom - if I can help shift a bath and have no problems then I think it's fairly safe to say that once implanted that little embryo isn't going anywhere. It is possible that what I did could have caused me to strain myself and that strain could have messed up stuff with the uterine lining and I could have lost the baby, or it could have interfered with the hormones, which again could have had a bad result, so I count myself very blessed that it didn't. I wouldn't recommend doing as I did to anyone!

The only time you should really avoid BDing is if you get some bleeding after sex - that's because of the placental location, and you can cause damage then.