Regarding the issue of the mom on combination ocs with diminished milk
supply... Why won't MDs believe this happens.  I have seen 3 cases in the
last month of diminished milk supply due to LOW-Dose OCs .  In all cases I
immediately switched the moms to Micronor , which is the progesterone only
pill (sometimes also called the mini-pill)  with grateful moms expressing
normal milk supply again in a few days.  This mom has several options but
if she wishes to continue on oral contraceptives I would suggest she start
Progesterone only pills as her next pill pack.  Several important
points...She must take them at the same time every day and they are less
forgiving in terms of missed pills and pregnancy. Also, there are no "sugar
pills"  in the mini-pill pack all are active and must be taken.  With her
desire not to be pregnant and her proven fertility I would Not advise her
to stop the pill without another plan!!!!  Mini-pills should not impair
breast milk production in any way.

Has she considered Depo-Provera?  It is more effective in preventing
pregnancy than having a tubal and has the added benefit of increasing the
milk supply in some women.  Women receiving Depo tend to have less problems
with supply and breastfeed longer than those who do not receive it.  She
could receive it now -with her period on the current pill pack and not have
to worry about a back-up method.

The copper IUD may also be an alternative for her.  Completely non-hormonal
it will certainly not affect breastmilk.  These are now approved for 10
years of use!  They are very effective and can be recommended in moms with
no history of STDs and monogamous relationship.  There was one study
implicating breastfeeding and IUD use with increased risk of uterine
perforation but this relationship has not been shown in other studies.
This could be inserted with her period coming up as well. Unfortunately for
women whose insurance does not cover it the cost may be prohibitive.
(Between $500 and $1000 in the US.)

Hope this helps.
Beth Hall CNM, MSN in private practice
in Maryland