Her male colleague would have dispensed with the honorific prefix o. Liberal use of honorifics is but one characteristic of the speech of Japanese women. Speaking in a high-pitched voice, using particular grammatical forms, and occasionally adopting childish affectations are some other speech styles of some but by no means all Japanese women. As often happens with a highly complex form of human behavior, Japanese women's language has received some strange press. Okaeri ni natte kara wa yoroshii desu yo.
Women also have a slightly different vocabulary from men.
The fact is that female speech differs from male speech in probably all languages to some degree. The difference is just more obvious in some languages, such as Japanese, than in others, such as English. With changes in gender relationships, that rule is less observed now than before, but it is still not entirely ignored. Incidentally, having a peculiar speech style is not a uniquely female characteristic in Japanese. Males have a somewhat smaller but no less colorful range of expressions and grammatical forms available to them to express moods ranging from quiet assertiveness to loud boastfulness.