Birth control in 1880s England actually owes a lot to a little book written in 1832 by a doctor named Charles Knowlton. The book Fruits of Philosophy was a summation of knowledge about both fertility and contraception. It's early publication and dispersal was limited. Knowlton shared copies with his patients and when it was picked up by a larger publisher for the second edition he was actually charged with blasphemy and imprisoned for a few months. For the next forty years or so the book would only sell about 700-1000 copies per year. It was one of many tracts on contraception and would probably not have gained as much notoriety if one of its publishers hadn't been prosecuted for selling indecent literature in 1876. Charles Bradlaugh and Annie Besant began publishing it in protest and aggressively circulated it. The resulting trial and publicity made the book a bestseller with 125,000-250,000 copies sold yearly.

You can read copies for free if you want to get an authentic taste of what someone might read. However it boils down to withdrawal, douching, using a sponge with a spermicidal solution inserted into the vagina and of course condoms. Condoms have a really long history. The first well-documented uses were linen condoms soaked in chemicals in the late 1500s as a method to prevent syphilis. By the 1800s these were almost completely abandoned in favor of skin condoms which were expensive but not as uncomfortable as linen.

In 1844 the process for vulcanizing rubber was patented. It didn't take long for people to apply the new technology. Rubber condoms were mass produced by 1855 and in 1876 a major factory was opened in England. Availability was limited by various decency laws but they were still obtainable if you knew where to look.

To sum it up within the confines of marriage douching was very popular as it allowed for reduced but still present fertility. If you were with a prostitute and you weren't too poor to afford it you wrapped it up, especially since syphilis was a huge threat. The only treatment for it was relatively expensive mercury containing ointments with horrific side effects such as insanity or death.

If the prostitute you're writing about is poor with poor clientele they may be relying on spermicidal douches if they can't convince johns to pull out. The materials for this method were widely available and cheap. Much less effective but did still have some benefit.

If birth control failed abortion could be tried. There were many folk remedies used but diachylon was a very common and cheap substance that was used to induce a miscarriage due to the high lead content. If a pregnancy was brought to term the child might be placed at a baby farm though this was more of an option for someone who could afford the initial fee.

Part of the reason for conflicting information is that prostitution was fairly common in diverse social settings. For example diachylon was much more documented among working class women whereas a governess might place her child at a baby farm.