My abstract was one of the top 500 scoring, do I need to present it at the Congress for it to be included in the BJOG supplement?

Yes, the BJOG supplement only includes abstracts presented at the Congress so at least one of the authors named on the abstract needs to be registered to attend and present either in-person or virtually. They will need to register by the early bird deadline (24th April 2023) to be included and further information will be sent to the successful author(s).