Low birth rates have history in Slavic lands for quite some time. This has nothing to do with western values, etc. that's just bollocks. Irish are western and they have pretty decent birth rates hell French aint that bad either. I have been there and yeah i saw many young Irish women with kids + pregnant.
Slovenia already had bad situation during communist Yugoslavia thats why we had to import other Yugoslavians. Nowdays i see lots of kids among Slovenes to be honest. Or at least in my area anyway. Basicaly east and south Slovenes are statistically destroying our birth rates. If it werent for them Slovenia would have pretty decent birth rates.