If she was really concerned about maximizing the ability to conceive they she shouldn't have been so
promiscuous without condoms. Many STDs can cause difficulty conceiving later, especially if not detected quickly.
That part isn't about her though, it's about her friend.
She was mainly asking whether her friend had sex with condoms or not, and said that she doesn't like condoms.
Whether she had done it herself before is unknown yet.
Also, while statistics do say that STD's/STI's are common, but a lot of people have sex with multiple partners without any protection and have been ok without any issues. And if they do get infected, majority of them are curable as well.
While there are people who never had sex with anyone other than their one marriage partner and got infected with STD/STI while just trying to conceive a child.
As for the major ones, well it's not like you have to have sexual relationship to get them.
Many have been infected by them by other means as well (mostly due to medical negligence).
In the end, whether you get a dangerous STD/STI or something like Cancer is upto your luck, that's all.
It's all a dice game. You roll a bad number and you are out, even if you have been playing carefully your whole life.