What exactly does the Catholic Church mean by the "Virginity" of Mary? Possible ways to understand "virginity" :


Some people may define it as no sexual event whatsoever.
Some may define as not having intercourse with a male.
Some may define it as not participating in any intimate acts with a male.
Some may define it as an intact hymen.


I have a problem with the last one, since a lot of girls are not born with a hymen, or the hymen can be damaged in sports activities. 

I can't see a logical reason to think that the Blessed mother was definitely born with one or didn't damage it with non sexual physical activity.

So, what exactly does the Catholic Church mean by the "Virginity" of Mary?
The Perpetual Virginity of Mary is one of the four Marian dogmas, the others being the Divine Maternity, the Immaculate Conception and the Glorious Assumption, which have so far been defined.

Pope Clement VIII in 1603 in Dominici Gregis condemned as heresy the error that the Blessed Virgin Mary did not remain  forever in her virginal integrity, before Christ's birth, in the birth itself, and perpetually after His birth.

This repeats the ancient formula


  ante partum, in partu, et post partum


or


  before giving birth, during the birth and after the birth.


So according to Catholic teaching, yes, Mary's hymen did remain intact during the  miraculous Virgin Birth of Christ. (It would hardly be necessary or seemly to take the phrase that she  remained a vigin during the birth as implying she did not have sex during the birth.) It is Catholic belief that Mary was assumed body and soul into heaven, with her body intact.

Article 510 of the catechism says:


  Mary remained a virgin in conceiving her Son, a virgin in giving birth to him, a virgin in carrying him, a virgin in nursing him at her breast, always a virgin.


http://www.vatican.va/archive/ccc_css/archive/catechism/p122a3p2.htm