I highly, highly recommend this. I battled yeast infections on my breasts and finally figured out that the yeast was living on my bras, cloth pads, etc. (even after washing). Once I washed all of those in hot water and vinegar (while also on a course of a prescription oral anti-yeast medication), it was the end of the yeast infections. I've heard that some people have cleared up infections without medication and in my case I tried non-medication routes as well, but ultimately, I did need medication in my case.
My DD did not develop thrush (I was EPing), so I can't advise on that specifically, but from what I've read, it is possible to pass yeast infections back and forth.
Good luck; I hope you and your LO feel better soon.
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