Re: Milk let down is not happening, is it low milk supply?
Welcome to the forum!
In general, as long as the baby is having sufficient wet diapers and is being nursed on demand, there's nothing to worry about. Letdown sensation often decreases or vanishes as time goes on, usually when supply adjusts to meet demand very precisely without a lot of milk left over. Many moms freak out at this point, mistaking normal, adequate supply for low supply.
However, since your perception of a decreased/vanished letdown coincides with you getting the IUD, it seems very likely that the IUD is the cause. The progestin IUD is less likely to cause harm to supply than combination estrogen-progestin birth control like the pill or patch, but some moms still experience significant supply reduction when using progestin-only contraception. Personally, if it were me I'd make an appointment to get rid of the IUD. All barrier methods (condoms, diaphragm, sponge, etc) are safe for breastfeeding, and the copper IUD (ParaGard) is as well.
Until you can get the IUD removed, nursing more frequently, pumping, and taking some fenugreek and eating some oatmeal may help you through.
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