ive had mine pierced for 20 years, NEVER have i ever had a smelly belly button. I think the other answering person might need some hygiene advice.

Ive got mine done I loooove it had it done since I was about 13. It don't affect my endo at all. I've had it out for long periods of time and not closed up. When u have any opp u have to take all piercings out when I had 1st lap I didn't put it back in until my belly button felt normal again and ill do the same next week. I remember it feeling odd for ages but Touching in my belly button makes me gag having stitches taken out of it was awful I felt violated lol but it's not actually in ur belly button it's in the skin above it. Sometimes when Ive had a really bad endo belly n I feel bloated like im going to split I'll take it out it makes no difference at all even tho I fort it would help. I no obvs it's odd to have metal in ur skin but my younger sister had her belly out the other day and it looked so strange where she hasn't got hers done n I'm so used to seeing. I'm not very blessed in the boob area so to me I look like a chunky boy when I haven't got it in n it looks so strange not on me to me. It's so silly it's a tiny little thing but makes me feel slimmer and female. If u want it done go for it Xx

My main concern would be heating pad + metal piercing haha, but if you are doing well and want one, I don’t think it would be a big deal

Your belly button is one of the dirtiest places on your body (dont believe me, stick your finger in your belly button after workjng out or not showering for a while and smell it). Sooo gross i know but it will make you change your mind. A piercing just increases risk of infection :/ yuck. I also had my belly button pierced, no interference with endo but its just really not the most sanitary place to have an open hole. Especially if you have a disease that already weakens your immune system.

If u have to have laproscopic surgery they go thru the belly button. So probably would mess with your piercing