A non-hormonal, reversible and non-toxic male birth control could be a step closer, with scientists successfully targeting a protein that's crucial in making fertile sperm. Knocking this protein out for a period of time would give men control over their protection window, much like oral…
IEDs have very negative effects, but you wouldn’t really call them side-effects.
And IUDs involve surgery which has its own risks including perforating the uterus, plus they can become infected and cause sepsis which is deadly, plus in general infections suck. Some women suffer immense pain which may or may not be ignored by their doctors. They also do release hormones which have fewer side effects because they’re more local, but they’re not side effect free.
Many of these issues were much worse in the earlier days, where many women died or suffered serious illness and permanent infertility whilst doctors didn’t take them seriously because women are often ignored by doctors where men would not be. So the level of safety the devices now have was bought with a lot of women’s unnecessary suffering.
https://www.verywellhealth.com/iud-risks-and-complications-906766