I'm reading Kidou Okamoto's Japanese novel right now. It was written in 1950 and its title is "半七捕物帳 01 お文の魂". I noticed that in this novel there are lots of female names that starts with お.

Here are examples: お文 お道 お春

What means お before names? Is it still common in Japan to give names that starts with お? Was it used only for female names or for male names too? How to read kanji after お - in 音読み or 訓読み?

Thank you in advance! It's really important for me because I'm trying to translate this novel to my native language.

Here is novel's link: https://www.aozora.gr.jp/cards/000082/files/1005_14977.html