ImportanceThe US Supreme Court ruling in Dobbs v Jackson Women’s Health Organization on June 24, 2022, revealed immediate and distinct differences between states regarding abortion legality. Whether the ruling was associated with population-level changes in seeking information on reproductive health care-related information is unknown.ObjectiveTo determine whether the US Supreme Court ruling on Dobbs v Jackson Women’s Health Organization was associated with increased information seeking for reproductive health care access in the states with immediately effective (trigger and pre-Roe) abortion laws vs other states.Design, Setting, and ParticipantsThis was a retrospective cross-sectional study of nationwide real-time internet search data by state-week from January 1, 2021, through July 16, 2022. Difference-in-difference event study estimates were used to evaluate abortion- and contraception-related internet searches after the Supreme Court draft majority decision was leaked on May 2, 2022, and the final ruling was issued on June 24, 2022, in states immediately affected vs other states. Data analyses were performed from July 18 to January 14, 2022.ExposuresThe Supreme Court’s draft majority decision leaked on May 2, 2022, and the final ruling on Dobbs v Jackson Women’s Health Organization on June 24, 2022. Preexisting state trigger laws and pre-Roe bans that became effective immediately when Roe was overturned by the decision on Dobbs.Main Outcomes and MeasuresNumber of searches per 10 million Google queries in a state-week for terms related to abortion or contraception.ResultsSearches for abortion-related terms increased from 16 302 to 75 746 per 10 million searches per state-week during the weeks before vs after the May 2, 2022, leak of the draft majority decision in states with trigger laws or abortion bans. This was a 42% (95% CI, 24%-59%) higher increase than in states with laws that protect abortion access. Searches for contraception also increased from 56 055 to 82 133 searches per state-week after the ruling in the states with abortion bans, 25% (95% CI, 13%-36%) higher than the increase in states protecting abortion access.Conclusions and RelevanceThe findings of this retrospective cross-sectional study suggest that changes in internet searching for terms related to reproductive health care can capture immediate population-level changes in information-seeking behavior regarding reproductive health care access. These data are critical for shaping health policy discussions.