A recent article in BusinessWeek drew attention to the fact that many female MBAs aren’t making it to the top. Why is this? Is there still a glass ceiling? Is the ceiling in fact made of reinforced concrete? Or is it that many women are opting out?

Clearly, there are going to be variations industry by industry, and I won’t profess to be an expert on many career paths. From my experience – solely in banking – I feel that many women eventually opt out rather than fight to get to the top. Unsurprisingly, I feel this is even more common for mothers than for women without children.

Female MBAs who go into finance are classic Type A over-achievers (as are many female MBAs more generally). They give 100% to whatever they do and are perfectionists. They want success and they want to achieve that success now. They also generally have husbands who are equally obsessive. At business school, many of these women not only received their MBA but also their MRS. Almost one third of the women in my business-school class married men from business school.

When both partners have a banking lifestyle, achieving a stable home environment is tough, particularly when children are involved. As you progress in seniority through a bank, the hours get more manageable but they are still long. You may not be working 24/7 any more but you are still working 7am to 7pm. It is an unpredictable, deal-driven, client-service business.

Senior executives still receive calls at random hours of the day and night. (My favourite was at 2am, from a client asking if we needed a meeting then or if I thought it could wait until the morning.)

Many banks do have family-friendly policies. I had understanding colleagues. We had free emergency crèche places, good parental leave policies, and a myriad of other things of which I didn’t fully take advantage.

With working husbands in the same industry, many female bankers could afford to make choices. Going from two incomes to one was a challenge, but possible. In theory, the man could have opted out. But, in reality, this was rare.

The current downturn and the flood of employees out of the market has changed all this. With jobs in financial services suddenly looking a lot less stable and lucrative, giving one up to spend time at home may start to seem a luxury.

On one level, this is a shame – stable families and children benefit enormously from having one parent at home. But on another level, it could increase the proportion of senior women in an industry which desperately needs them.