No periods but pregnant?

I only know of two contexts where you can readily not have a period but become pregnant- after a miscarriage and when breastfeeding, times when you're actually really fertile.

I have a heard of a few cases of women who were not having periods, due to PCOS or a hormonal imbalance, but who got pregnant anyway, but this does not seem to be the norm.

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About Cassaundra Owens
Birth: February 13
On Moms.com since: Oct 11, 2013
I'm a little strange, pretty green, and learning to live life as a wife, future mother, and entrepreneur. Right now, my husband and I are trying for our first after 3.5 years of infertility and 2 losses. Viva la adventure! Join me too at MortalMommy.com!