You’ve just received a salary offer. Being a woman, you know that women on average earn less than men, and that women’s reluctance to negotiate could contribute to this differential. So – should you negotiate?

On the one hand, you’ve repeatedly been told that you should negotiate a salary offer, and you know this advice is not specific to you. Recent polls confirm that 70% of respondents believe women should negotiate their salaries more often and 69% are more likely to encourage women than men to negotiate.

But in reviewing the literature, you find that there are cases where caution may be warranted. When women aren’t sure what is expected in negotiations, or those expectations are murky, research shows that asking for more money doesn’t always work as well for women. In fact, women – more than men — may experience a backlash that can hurt their future career prospects.

You consider your current situation and decide that these concerns aren’t relevant. If you decide to negotiate, you will be matched with a person from HR, who is required to keep your negotiation process confidential – thus, backlash will be limited. You and your HR contact will be negotiating via email, so the face-to-face pressure is off. Both you and HR know the skills and experience you bring to the table. Your friends and family encourage you to “lean in,” citing the higher salaries or bonuses they got just by asking.

Even so … you don’t think you should. You decide not to negotiate. Not this time. You lean out.

Is it a mistake to lean out?

If you’re like the women in our recent study, you’re right to listen to your own instinct about when to negotiate. In experiments we conducted, we saw that women hurt themselves financially when they followed a blanket recommendation to always ask for more.

In our lab study, “workers” and “firms” negotiated via anonymous chat messages, to reduce the risk of backlash – because the chat is anonymous, the participants’ genders are unknown. We also established a “market value” for the workers by having them complete a set of tasks; both the workers and the firms knew how the workers had performed and what they brought to the table. We ran two versions of this study: a “choice treatment” in which workers were offered an initial wage and had to decide whether they want to accept it or instead enter negotiations, and a “forced treatment,” in which workers still received an initial wage offer, but were required to always negotiate. As can be the case in a real salary negotiation, negotiations that fail to reach an agreement result in a financial cost for both the worker and the firm.

Confirming the results of previous research, we find in the choice treatment that women are 11% less likely to enter negotiations than are men, and this gap arises despite the fact that those who enter negotiations almost always gain from doing so.

So why are women not entering negotiations more? To answer this, let’s note that it is not that women never negotiate. Indeed, it depends on the conditions of the negotiation. Women who are given an initial offer below what they bring to the table reject the wage and initiate a negotiation 88% of the time. The reluctance to negotiate is instead seen when the initial wage offer equals or exceeds what a woman brings to the table; in this case, only 44% of women negotiate. While women largely gain from negotiating, they are less likely to enter negotiations when they are already being paid at or above their market value.

Still, since women on average do gain by negotiating, what would happen if we simply forced them all to negotiate? To answer this question, we compared the outcomes women achieved when they avoid some negotiations (in our choice treatment) to when they always negotiate (in our forced treatment).

Across all negotiation opportunities in the choice treatment, we found that 49% of the time women secure a final wage that exceeds the initial wage offer and 9% of the time they receive a final wage below the initial offer. The remaining 42% of cases, where the final wage equals the initial wage offer, was largely driven by women avoiding negotiations 34% of the time.

To determine if avoiding negotiations 34% of the time was financially wise, we examined how the distribution of wages changed when women were instead forced to negotiate every time. When women were forced to negotiate every time, women’s overall wages actually decreased. To put a finer point on it: final wages exceeded the initial wage offer at exactly the same rate as when they had a choice to avoid negotiations – 49% of the time — but the rate by which final wages fell short of the initial wage offer increased from 9 to 33%.

Comparing these two scenarios, we concluded that when women in our choice treatment opted out of the negotiation they made a financially wise choice.

Should women just lean in?

Our study serves as an important reminder about selection. Ignoring selection — about who enters negotiations when — allows for misleading policy implications.

For instance, the finding that the women who enter negotiations gain from doing so cannot be seen as an indicator that all women — independent of the negotiation circumstances — should always negotiate. Women in our data opted out of negotiation circumstances that were likely to be costly.

The results of our study suggest that a blanket policy recommendation – that all women should always ask – may backfire. A more nuanced approach may be advisable. Along with improving negotiation skills and helping individuals better assess what they bring to the table, we need to acknowledge that depending on skills, circumstances, and potential downsides, there may be cases where it is better not to ask. In light of such complexities, women may be good judges of whether or not they should lean in.