Jennifer,
I've wondered some of the same things. I, too, experience long lactational
amenorrhea (not as long as yours, but up to 23 months). I also have nipple
sensitivity during ovulation. And nursing now while I'm pregnant is quite
uncomfortable -- in fact, I'm really discouraging my 3 year old now because
of the level of discomfort. You point about menarche is very interesting. I
developed breasts early (By 10 I needed to wear a bra). But my periods
didn't start for nearly 3 more years. I felt like I was the only girl in
8th grade who hadn't started!  My periods as an adolescent were very
irregular. Then as an adult, I have generally had a fairly long cycle -- up
to 36 days.  All of these factors do seem to support your hormonal theory.
I would be very interested in learning if any studies exist in this area.

Glenni Lorick, BSE, IBCLC
Lima Peru
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