It is in fact quite easy. There Male and Female suffix in many slavic languages, especially in the Czech/Slovak language.
The suffix -ova, means basically : Belongs to..
so this means the females surname in this case basically means : belongs to ...
Now, each girls surname since her born "belongs" to her father´s surname.
Example: hypothetically your name is John Watson, you have a daughter, in CZE/SVK her surname will be Watsonová, just like all her sisters and mother.
They carry this surname until they get married, then they receive the husband's surname and add the suffix.
Example: Her husbands name is for example John Johnson, so when she get married, her surname then "belongs" to her husband, so in CZE/SVK her surname will be ... Johnsonová., just like her future daughter(s) etc...
so for example Slovak biathletes: Fialková (father Fialka), Poliaková (father Poliak), Gereková (father Gerek) etc...
+ there also one exceptions. If the male surname finish by -ý. Like for example Suchý, Malý etc... the females suffix will not be ová but -á. Suchá, Malá etc...
for example our former tennis player Martina Suchá (father Suchý)