Re: 19 months--still no period?
The level of nursing you're doing is generally not enough to result in cessation of menses. On average, nursing mothers get their periods back at around 15.5 months postpartum, though many will get their periods back sooner and some will go longer. Fertility tends to return when moms go >6 hours without nursing, which is why the return of fertility often coincides with a baby sleeping through the night or transitioning to a majority solid foods diet.
You've already had one period and you have a Mirena. To me, that suggests that Mirena is what is keeping your cycle away, not breastfeeding. If it was breastfeeding, you wouldn't have had that one period at 9 months; once your period returns it's very unlikely that breastfeeding can chase it away again, not without some sort of hormonal assistance- and that's where the Mirena comes in. Right?
So I doubt that you need to wean in order to conceive. Or if you do, that's a bridge you cross when you come to it- when you're ready for another baby and after you have had the IUD removed.
That being said, yes, do talk to your doctor! If you ever have a question or concern, they should be there to answer it.
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