Who gets to decide? Why should the restaurant or the mayor or anyone other than the person consuming the alcohol be deciding this, unless the person is inebriated to the point that the bar/restaurant would no longer serve her?
OTOH, the title is quite misleading, as if the mayor is FORCING the restaurants to serve alcohol to pregnant women, when that is clearly not the case.
The restaurant decides whether or not to serve, The pregnant woman decides whether or not to patronize the restaurant.