Pat: Tri-Levlen is one of the many "tricyclic" combination
estrogen/progesterone pills, similar formulation to Triphasyl. Unlike
standard, combination pills, which have the same amount of estrogen and
progesterone throughout the cycle, tricyclics have a phased formulation with
changing proportions of estrogen to progesterone every week (supposedly
to "mimic" the normal cycle). Although I don't know if anyone has
analyzed the difference between monophasic and triphasic pills in terms
of their effect on lactation, I presume these would be just as likely to
reduce the milk supply. The patient should probably stick to a
progesterone-only pill. Alicia. [log in to unmask]