In slovak language, female first names always end by a (I know of NO exception, except the non-slavic names sometimes the snobs like to give to their daughters here). Similar rules work in other slavic languages, too, although maybe no so stringent.

In most slavic languages, the surname has a female form, too, usually by adding a suffix (-ova, most often). Again, it is a sign of snobbism if a woman omits this from her name, and is very rare.

For example, you might probably know the tennist, Martina Navratilova (she's of czech origin).
Just as a curiosity.

JW