Background:Physicalactivity(PA)duringpregnancyprovidesphysicalandpsychologicalbenefitsformotherandchild.U.S.guidelinesrecommend≥30minofmoderateexerciseforhealthypregnantwomenmostdaysoftheweek;however,mostwomendonotmeettheserecommendations.Theoryassistsinidentifyingsalientdeterminantsofhealthbehaviortoguidehealthpromotioninterventions;however,theapplicationoftheorytoexaminePAamongpregnantwomenhasnotbeenexaminedcohesivelyamongmultiplelevelsofinfluence(e.g.,intrapersonal,interpersonal,neighborhood/environmental,andorganizational/political).Subsequently,thissystematicreviewaimstoidentifyandevaluatetheuseofhealthbehaviortheoryinstudiesthatexaminePAduringpregnancy.Methods:ArticlespublishedbeforeJuly2014wereobtainedfromPubMedandWebofScience.Inclusioncriteriaappliedwere:(1)empiricallybased;(2)peer-reviewed;(3)measuredfactorsrelatedtoPA;(4)comprisedapregnantsample;and(5)appliedtheory.Fourteenstudieswereincluded.Eachstudy'sapplicationoftheoryandtheoreticalconstructswereevaluated.Results:VarioustheorieswereutilizedtoexplainandpredictPAduringpregnancy;yet,themajorityofthesestudiesonlyfocusedonintrapersonalleveldeterminants.Fivetheoreticalframeworkswereappliedacrossthestudies—allbutoneattheintrapersonallevel.Fewdeterminantsidentifiedwerefromtheinterpersonal,neighborhood/environmental,ororganizational/politicallevels.Conclusion:ThissystematicreviewsynthesizedtheliteratureontheoreticalconstructsrelatedtoPAduringpregnancy.Interpersonal,community,andsocietallevelsremainunderstudied.Futureresearchshouldemploytheory-drivenmulti-leveldeterminantsofPAtoreflecttheinteractingfactorsinfluencingPAduringthiscriticalperiodinthelifecourse.
