During swimming water enteres my vagina and then leaks out while I am getting changed. Once, a few days before my period was due, the water had brownish period blood in it. I have just found out I am pregnant (my fourth baby) and am wondering how far inside me the water goes and if the chemicals in the swimming water may harm the baby?

Swimming during pregnancy, with doctor's permission of course, is very healthy! While you may think the water enters your vagina, it will not cross the cervix. Even if it does cross the cervix, it does not enter the placenta.

The placenta is much like an egg, if you think about it, in that you can break the shell, but without breaking the shell, nothing can enter it.