When Miriam Labbok was in Australia last year she spoke on fertility,
birth control methods and breastfeeding.  She has extensively
reviewed all the literature, plus I think she may have been involved
in studies at Georgetown. As I recall, she was clearly saying that
the combined pill was a problem, and she was the first "expert" who
I have heard say that the minipill can also be a problem.  I think
she was differentiating between brands and how some components may
be metabolised into oestrogen-like substances.

I'm out of my depth here, but this is the direction you might like
to follow for more information.

Ros Escott
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