I would not enjoy a story that made fun of abortion, which is too serious an issue for me, but I would not challenge an author's right to express whatever ideas he has in a story.
In a similar way, I have my personal views on abortion, but whatever people think about it, they tend not to be swayed by any argument. My own view is that whatever the justification, to abort a child is exactly like giving the death sentence for a parking offence, but I also accept that there are situations when the interests of the mother should take precedence. What I don't accept is abortions carried out purely for social or economic reasons, and mostly abortion is carried out for what I see as purely selfish reasons.
I don't associate opinions on abortion with those on prostitution, or anything else, but there are groups of people with the same view on a combination of topics. They call the larger ones political parties, and sometimes the smaller ones are called pressure groups.
On prostitution, some good views have been expressed here. If there was a way to decouple prostitution from crime, drugs etc. that is where I would want to go. Prostitution can be and often is a particularly appalling form of slavery in which the prostitute's personal dignity and even her protection from disease are surrendered. Some men will never treat a woman with respect, so I will not pretend that even in an ideal world prostitution is going to be a nice profession, but at least it can be voluntary, and a prostitute can have health care and protection from criminal exploitation.