The mom will almost never say that she wants to go and get smashed, I
generally ask her plans for the evening and am pretty sympathetic about her
wanting to have a social evening out.   I usually talk to moms about the
different way women and men drink, many women drink a glass of wine or a
beer slowly...to pun, nurse it along, while many men drink more rapidly.  I
always take the extra time to talk and laugh about wanting to get out and
how dad is getting a little cabin fever.  We talk about being sure to eat
first, and take their time with their drink, generally that puts her
drinking 2-3 drinks over about a 3+ hour period, and this seems to not be a
problem.  I remind her that if she gave up alcohol during her pregnancy, she
may feel woozy with the second drink, which means to slow down and also get
something to snack on.  We talk about cheese helping minimize the alcohol
(don't ask me where I heard that, I'm too ancient to remember, maybe during
my own drinking years, many, many years ago).  Reassure mom that one or two
drinks after having a meal will not hurt her baby, it's only when she gets
drunk that she should be concerned.  We talk about how long it takes for the
alcohol to dissipate.  And how to be sure baby is doing ok while she is
gone.  A hint for this is that mom keeps the car keys, they go someplace
within 15 minutes of their home (if at all possible), when they arrive mom
calls home to check on things, then she checks in with the sitter every
hour.  If baby is upset, she goes home and nurses the baby and gets him back
to sleep and then returns to join dad and friends.  She doesn't make a big
deal about needing to leave, nor returning.  They plan in advance to be home
in a few hours, not a long night of partying.  In today's pager society of
the USA, most families have a pager or cellular phone and the sitter can
call/page as needed.
    Jacie in Albuquerque, New Mexico, where I just finished "My Fair Lady",
3 weekends, 10 shows!  I'm pooped and can't believe I am so addicted to this
that I am doing this every night before bed!