Married people should not have to avoid sex.
I've sat through more than one pharmacology class. I believe most contraception is non-abortifacient because it actually is non-abortifacient when you look at the mechanism of action of the drugs in question.
The Orthodox church has no official stance on contraception. If one hates children and that is their reason for using it, then that shows a deeper spiritual issue that needs to be addressed. However, while the Church does have strict fasting rules (which includes abstaining from sex during those times), contraception isn't banned. I don't think contraception is considered ideal, however, in the Orthodox Church the concept of economia is practiced. Divorce and remarriage are also allowed in the Orthodox Church, but it operates on the same premise. It isn't considered ideal, but allowing it can keep people from sinning or turning to Christ.