I have been on SSRIs for 20 years. For me they’re a good idea, but I’ve known others who have had a terrible time with them.
Sexual dysfunction is definitely a thing: how much of an issue that will be is going to be a personal decision on weighing up pros and cons. If your sex drive is low as a part of your depressive symptoms or you’re already experiencing anhedonia (inability to feel happiness/pleasure) or anorgasmia (inability to achieve orgasm) then going on SSRIs isn’t going to make that any worse. But for others the risk of missing sexual pleasure might be an unacceptable trade-off.
For anyone starting SSRIs I think it’s best to go slowly and keep in touch with your primary doctor throughout the process. There are a number of SSRIs available, and if one doesn’t work out you can try others, and hopefully land on one that works for you.
With all that said, SSRIs don’t work for everyone. It’s not unusual to feel weird or like things are getting worse when you first start them: it takes some time for the effects to settle. But if you’re having a really bad time on them, speak to your doctor about alternatives.
I don’t know anything about its effect on fertility. I know people who have conceived while on SSRIs, but that’s purely anecdotal.
It’s going to be a judgement call on your part. SSRIs have been in use for long enough that I would expect there’s a big pool of data around fertility rates, even if it’s not had much analysis done on it. Also, rat models are useful but need to be understood in their context. One study in rats is not overwhelming evidence.