At first blush, new research about ovulation cycles makes sense, though in a dark way.

It appears that many women, for a week each month, will leap at a chance to boost their status among other women. They're also more willing to throw other women under the bus.

Duh, right? Except it's not what you think. Save your PMS jokes for the bar.

The kicker is that these findings have implications for how women shop — and they're kinda creepy.

Vladas Griskevicius, an associate professor of marketing and psychology at the University of Minnesota, is one of the authors of "Money, Status and the Ovulatory Cycle," a research paper done with fellow marketing researchers at the University of Texas at San Antonio. They found that during ovulation — that almost imperceptible stage when the ovary pops out an egg — hormones compel women to appear more desirable to men as mating partners.

OK so far.

But researchers wondered if more was going on than simple seduction. Female primates often become more aggressive during a phase of a menstrual cycle, so could female humans also get more competitive?

The short answer is yes. Here's one example:

Study participants were given this hypothetical choice: Choose to receive a $25,000 car while other women get $40,000 cars, or choose a $20,000 car with others getting $12,000 cars. When the women were not ovulating, the vast majority chose the more expensive $25,000 car, what researchers called an "absolute gain."

But when asked again while ovulating, more women chose the $20,000 car. The rationale: They now preferred that car because it raised their status compared with the others with their $12,000 cars — what researchers called "maximizing relative gain."

The report suggests that marketers could know that for one week a month, millions of women are vulnerable to sales pitches that offer to make them better than other women.

But which week? How would, say, Revlon know?

Let's go back a few years to a semi-notorious story in the New York Times about how Target knew which shoppers were pregnant, based on new purchases of products such as unscented lotion and vitamin supplements. The store might then send them baby-related coupons.

(The semi-notorious part came from the story's punch line in which a teen's father stormed into a store, demanding to know why she was getting ads for maternity clothing and baby cribs. Turned out she hadn't yet told him about his upcoming grandpa-hood.)

In much the same way, the U study suggests that marketers could use women's 28-day buying histories of, say, tampons to track where they are in their ovulatory cycle. Then, "firms might strategically send marketing messages (e.g., on mobile phones) that emphasize female competition specifically when female consumers would be most responsive to such appeals," according to the study.

In plain English: You're between menstrual periods, strolling through the store aisles. Your phone pings, and there's an ad for a new mascara that will make your lashes thicker/longer/better than any other woman's lashes.

On this particular week, you just might kill for that mascara.

Creepy? Exploitative? Brilliant? Could be a little of each, but from Griskevicius' perspective, research is research.

"Imagine if you invent a knife," he said. "You say, 'Wow, this is a knife. Wow, you could cut rope with it and build things with it.' Then someone else picks it up and stabs you.

"You can say, 'No, this isn't a weapon. This is a tool!' But you can't predict who will take advantage over us."

Could this really happen?

In some ways, it's already happening. Many stores track our purchases. Search for a particular car on your computer and suddenly ads for Toyota appear on the margin.

Griskevicius said it would behoove all of us to become more aware of the marketing forces in our lives. In this case, there is one other defense.

Study participants were filtered to eliminate women taking hormonal contraception or prescription drugs. Contraception disrupts hormones, thus erasing any behavioral effects around normal ovulation, he said, short-circuiting such status-laden sales pitches.

And, while the study may seem to have a high "What the?" factor, Griskevicius said that it rights some perennial wrongs.

"If you track the research history of how hormones influence behavior, we think about testosterone, and most of that research completely ignored women," he said. "After decades of research showing how hormones influence men's behavior, this is like, hey, wait a second, they influence women's behavior, too."

OK, given these findings, is there any upside here? Maybe, but it involves being creepy, exploitative and brilliant.

In one of the exercises, researchers gave a woman $5 to divide between herself and another person. Past research has shown that people tend to offer more money to women than to men.

However, the study found that when women were ovulating, they gave smaller amounts of money to other women — and more to men.

So if you have a female boss, and can figure out when she ovulates, that could — depending on your gender — determine when to ask for a raise.

The trick, of course, is figuring out her cycle.