What could be going on?

Question

Hi Ladies, I got the Kyleena IUD inserted in June of 2019. Before that, I was not having periods anymore due to being 300+ pounds.
I think blood must have been stored up from all the periods that I missed, because I bled heavily and was in a lot of pain after insertion. The bleeding slowed down in August and finally stopped by October. 
So it's now May and I have not had any periods since the bleeding stopped in October. But suddenly I am cramping and spotting and there's blood on the condom when my husband has sex with me. 
Is this an issue with my IUD? To suddenly get a period?
The only explanation I can think of is that I have been consistently taking metformin and ozempic injections since December. It made me lose 12 pounds. Is it possible that I lost just enough weight to get periods again?

Answer

Irregular periods are a common side effect of hormonal iuds. 
This includes heavier bleeding, longer bleeding, spotting, spotting between periods, periods closer together or farther apart, or no bleeding. Usually happens with the first 3 to 6 months but can happen anytime during the use of the iud. 
If you have mirena up to 20% of users stop getting periods and its the only fda approved birth control to help treat heavy periods. Kyleena stops periods in up to 12% of users and skyla stops periods in up to 6% of users. Youre most likely to have irregular periods with kyleena and skyla because they're lower dosages than mirena. 
Mirena is 52mg of levonogestrel, kyleena 19.5mg of levonogestrel and skyla 13.5mg of levonogestrel. 
I have mirena and my periods stopped after month 4 which is what I was hoping for but most people on any iud still have periods.

What could be going on?

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