s ▁div es . ▁D iving ▁during ▁pre gn ancy : ▁The ▁change ▁in ▁risk ▁of ▁decom pression ▁sick ness ▁during ▁pre gn ancy ▁is ▁unknown , ▁and ▁it ▁is ▁considered ▁un eth ical ▁to ▁conduct ▁experiments ▁with ▁an ▁endpoint ▁of ▁sympt om atic ▁decom pression ▁sick ness ▁in ▁pre gn ant ▁women , ▁so ▁data ▁is ▁unlikely ▁to ▁accum ulate ▁sufficiently ▁to ▁allow ▁the ▁risk ▁to ▁be ▁ass essed ▁real ist ically . ▁The ▁pre ca ution ary ▁principle ▁suggests ▁that ▁the ▁risk ▁should ▁be ▁avoided ▁by ▁not ▁div ing ▁when ▁pre gn ant . ▁A ▁history ▁of ▁div ing ▁during ▁early ▁stages ▁of ▁pre gn ancy ▁is ▁not ▁considered ▁likely ▁to ▁have ▁ad verse ▁effects ▁on ▁the ▁fet us , ▁but ▁the ▁recommend ations ▁are ▁to ▁avoid ▁it . ▁D iving ▁while ▁med ically ▁un fit ▁to ▁d ive : ▁S aw - to oth ▁d ive ▁profile : ▁In ▁a ▁saw ▁to oth ▁profile ▁the ▁diver ▁asc ends ▁and ▁desc ends ▁a ▁number ▁of ▁times ▁during ▁the ▁d ive . ▁Each ▁as cent ▁and ▁descent ▁increases ▁the ▁risk ▁of ▁decom pression ▁sick ness ▁if ▁there ▁are ▁any ▁b ub bles ▁already ▁in ▁the ▁diver ' s ▁t issues . ▁The ▁increase ▁in ▁risk ▁depends ▁on ▁the ▁as cent ▁rate , ▁magnitude ▁and ▁duration ▁of ▁the ▁up wards ▁exc urs ion , ▁the ▁s atur ation ▁levels ▁of ▁the ▁t issues , ▁and ▁to ▁some ▁extent ▁the ▁time ▁spent ▁after ▁returning ▁to ▁depth . ▁Acc ur ate ▁assess ment ▁of ▁the