The issue is a little more complicated than it sounds here. Allergan has had a boys club reputation forever, and it's deserved. There is no effort to change that, either. HR and employee development are a bad joke. A few years back, they had a program for "executive women"; it was laughable and exposed how clueless HR and management are about these sorts of issues.
But the biggest problem at Allergan is that there is zero commitment to a reasonable balance between work and family, and that applies to men and women. The company is proud of being "lean and mean", "working hard and playing hard", sports talk, drinking a lot and all that crap. Many of my male colleagues have decided that they aren't going to sacrifice their families for the company, either, and if that means not getting a promotion, so be it. You have to give up a lot to advance here--look at the women who have--there are only a handful in middle and upper management. Look at the ratio, then look at the men and see how many of them have wives who don't work outside the home.
If there were an upper management commitment to being a better company, it would happen. There isn't, so it doesn't. But they can always talk about the stock price (forgetting, of course, how much they have and how little everyone else has). Why do you think the survey to be considered as one of the 100 Best Companies in America sank without a trace?? Obviously, Allergan isn't close to being on that list...