Depends on the type of BC. If menstrual periods return healthy and consistent that should be the green light. Get off BC asap and learn to track the cycle. I tracked my cycle religiously for years after I came off of hormonal BC to understand my fertility and as soon as we got married we tried and welcomed a healthy boy 10 mo later. Sadly had a miscarriage at 8 wks with our second try, but now 5 mo pregnant with a girl after our third try at 36 and 45 yo. I’m not sure if it’s a coincidence but I also timed conception so I’d have a boy first and a girl second, next ones will be freestyle! Best of luck to your friends!!