 [ Symptoms ] when can i stop using baby formula water for formula and start using either tap or jug water i buy for a water cooler  my baby is 3 months and we are still buying formula water i was wondering how long we would have to do this my husband and i drink water from a water cooler we buy replacement jugs for but it only comes out cold we also have city water which we cook with but do not drink [ Disease ] i think it would be highly unlikely that you could get pregnant in this manner however if you are not on an effective birth control or your partner does not use a condom there are many other ways this could happen if you do not get your period you should take a pregnancy test in a week or so