R.J.
I developed folliculitis when pregnant (10 years ago). My OB said it's one of the many unsung "joys" :P common to pregnancy.
In general they're EITHER
1) hormone related (some women get acne, others get folliculitis, whee).
-or-
2) weight related (as the skin stretches, the hairs get lost trying to exit... and the follicules get irritated, then infected). Most commonly found along bikini line, jaw line, and armpits.
No idea if this is what you've got... but it's what I had (and still have on my bikini line. since my skin is still stretched out :P)