The original American dubbed version contained the phrase "From a far away place and time, Earth's greatest adventure is about to begin" in text at the beginning of the intro. Curiously, about 10 episodes in, this was dropped, and the first screen of the intro was just the same background with no text.
The American opening theme music is the same as the Japanese version song, Miracle Romance, however it has been given English lyrics that are actually about Sailor Moon (as opposed to the generic romantic lyrics of the Japanese version).
The originally-aired version that aired in syndication on local networks featured a "Today on Sailor Moon" preview segment, narrated by the characters. This is not present on any other airing, including the later USA airings of the same dub.
The dub version of the show that aired on local networks in syndication and on the USA Network featured a Sailor Says segment following the end of the episode, which gives a positive message to children watching, not unlike what a lot of American cartoons of the day did.
The version that aired on syndicated local networks featured a Seagull Entertainment production bumper following the credits. The version that aired on USA was exactly the same but featured a Program Exchange bumper instead.