Is that a luteal phase shopping bag? © 2009 Jupiterimages Corporation

Women, hide your credit cards when your period is around the corner! That is, if  you buy the findings of a recent psychology study out of the UK. With somewhat predictable results, a pair of psychologists surveyed women about their menstrual cycles and shopping habits and found that not only does PMS bring along delightful mood swings and cramping, it may also lower women’s shopping restraint. Nearly two-thirds of the women polled bought something on impulse during the pre-menstrual/luteal phase of their cycle.

While I don’t doubt that menstrual hormones can impact female behavior, the study left me wanting. Particularly, what were these women impulse buying and how much did it cost? To me, impulse shopping a few hundred bucks away during that time of the month seems far more significant than, say, kneejerking for a tube of lipstick or a new book. Full disclosure: I only had access to the study abstract and a Miller-McCune article reporting on it, so perhaps that information is discussed inside. At the same time, my confidence in the study slipped even more when I stumbled on this Sheconomics paper from study author Karen J. Pine, which postulates that women’s spending is emotionally driven. From the executive summary:

Six out of ten women confessed to buying goods on impulse, one in four had regretted buying something and a third had spent more than they could afford, in the past week. During that period seven out of ten said that they had worried about money.

Again, what were these women buying and for how much? I don’t doubt the statistics, but I’m also not swallowing the conclusion that “emotions seem to be both the cause and the
consequence of spending money for many women” until I see how men match up. I’d place a solid bet that women and men’s impulse shopping take place in different settings and revolve around different merchandise and activities, and if you asked a similar group of guys the same questions about their spending habits, comparable patterns would emerge.

These “women as period- and emotion-driven spenders” theories also raise red flags because they seem to directly contradict data sizing up women and men’s performance in the financial sector. Since economic bottom dropped out, the media have pondered whether the recession would’ve hit as hard with more women running Wall Street by providing estrogen’s prudent balance against testosterone’s risk-prone ways. In the real world, that hormonal theory appears to bear out. From Big Think:

According to BusinessWeek, hedge funds run by women turned an annual rate of return of 9% between 2000 and 2009—versus 5.82% from funds run by men over the same period. A study by U.C. Davis researchers also found that men in the financial industry make 45 percent more trades than their female counterparts do—a gap that reduces their net returns by 2.65 percentage points per year compared with the 1.72 percentage points women lose on trading fees.

So how can women simultaneously be emotional spenders who splurge pre-period and also financial geniuses who make less impulsive decisions that end up fattening the coffers? Clearly, some of the math in this “sheconomics” equation isn’t adding up.

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