You could be dealing with reverse causality here, the drop in milk 
production could cause the menses and return of fertility.

I would advise plotting growth charts for both children and asking a lot 
of questions about breastfeeding management early on. Hypothyroidism can 
certainly cause milk production issues, depending on age of onset. For 
this baby, mom might want to ensure that she calibrates her milk 
production artificially high - avoid labor meds and separation from the 
baby postpartum, initiate breastfeeding within two hours of birth, keep 
the baby skin to skin thereafter to allow very frequent bf, and hand 
express extra colostrum after feedings during the first three days 
postpartum. And have her thyroid replacement levels checked to ensure 
she's well in the normal range, not just borderline.

Catherine Watson Genna BS, IBCLC  NYC  cwgenna.com

On 1/8/2014 2:37 PM, Laura Spitzfaden wrote:
> PTP.
>
> I am looking for others' experiences with sudden milk-supply drop two weeks before postpartum resumption of menses. Unlike other moms I know, this supply drop is permanant and does not bounce back. My first thought is insulin resistance relating to onset of menses but I thought I would also ask here if anyone has other ideas.
>
>  From the mom...
>
> "I am currently 15 weeks pregnant with our third child and eager to find
> resources now who may be able to brainstorm some possible reasons behind
> the sudden and extreme dip in supply I experience from ~2 weeks before the
> onset of my first postpartum period (around 3-4 months pp) until baby has
> started solids (around 7 months old, using BLW principles), as well as
> possible solutions. "
>
> This mom has help and support from LLL and has used a Lact-Aid to supplement at the breast for each of her children. She has no signs of IGT and no PCOS. "The conditions we know we are dealing with are hypothyroidism (treated
> with Synthroid) and Antiphospholipid Syndrome (an autoimmune blood clotting
> disorder). "
>
> Thank-you!
>
> Laura Spitzfaden, LLLL, IBCLC
>
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