Dear Mona,

Could you tell me how many couples decide not to know their baby’s sex? How much does this change depending on whether it’s the first pregnancy or not? I will be a father in a few months, and I have started discussing this topic with my wife and friends who already have children.

Thanks,

Thomas, 32, France

Dear Thomas,

Congratulations! I’m not surprised this question is of interest to you — it’s also of interest to some doctors. They’ve been studying parents’ attitudes toward the sex of their unborn children because in some cases, doctors believe the decision to terminate a pregnancy is based on the sex of the fetus — which raises ethical questions for medical practitioners. And yet, despite the interest in the topic, there is little reliable data on how many parents decide to find out if it’s a girl or a boy.

So my starting point is a study conducted in 2001. A team of doctors from Harvard Medical School in Boston issued 1,340 questionnaires to mothers-to-be and their male partners who were present. They found that overall, 58 percent of women and 58 percent of men said they had found out or planned to find out the sex of the fetus. (Sorry, I don’t have numbers on how many respondents said they didn’t want to know, so I can’t answer your question directly.) Already, you’re in the minority of parents, Thomas, since you told me that you and your wife are leaning toward not finding out.

Your indecisiveness about finding out the sex at this stage in your wife’s pregnancy also puts you in the minority. The researchers observed that “almost all parents feel strongly one way or the other about whether it is best to know the fetal sex before birth.” But most parents (84 percent of mothers and 80 percent of fathers) say they don’t have a strong preference about the sex of the baby.

Women who got pregnant accidentally, those who were planning a major move or renovation based on the sex of the baby and women who said the baby’s sex would influence their future childbearing decisions were all more likely to know or plan to find out the sex.

As for the second part of your question, Thomas — does it make a difference if this is the first pregnancy or not? Well, 62 percent of women with only one child wanted to find out the sex of the fetus compared with 55 percent of women who didn’t yet have any children.

But there’s more to it than that. Family configurations seem to matter a lot. Women who already had one or more children of each sex were just as likely as childless women to want to know the sex. (I realize I’m talking about only women here — the researchers presented the findings that way because they found so much overlap between partners’ responses: Only 2 percent of fathers wanted to learn the baby’s sex when the mother did not, and only 3 percent of mothers wished to find out the sex when the father did not.)

Beyond stated preferences, demographics seem to affect the likelihood of wanting to find out the sex of the fetus. The study identified a few statistically significant variables, such as age — men and women who were younger than 22 or older than 40 were more likely to want to know the fetal sex. Being unmarried, nonwhite and less educated also increased the likelihood of wanting to know the sex of the fetus, and being Catholic made it much less likely.

The researchers allowed respondents to select from a list of reasons why they wanted to find out the sex of the fetus and to write their own responses. The most commonly chosen reasons were “planning/preparation” and “curiosity,” but, as ever, the qualitative responses written in the respondents’ own words are just as revealing. The answers included:

“Lost a baby boy — apprehensive about having a boy.”

“Provision of some possibly illusory sense of control.”

“My mom has been fighting breast cancer and might not be with us when the baby is born. If this hadn’t been the case, we probably wouldn’t find out.”

Those who didn’t want to know the sex also gave their reasons. Most selected “surprise at birth/suspense,” but again they had the chance to provide more personal answers. Responses included:

“Tradition.”

“Don’t want to get too attached in case of problem.”

“There is nothing better than the doctor telling you what you have just brought into the world. I love surprises, and there aren’t really opportunities for true surprises as an adult.”

I wanted to check the Harvard team’s findings against some other studies (preferably more recent ones!), but as I mentioned before, the research on this really is scant. The best I can find is a 2012 study by researchers in the Netherlands that found that 69 percent of pregnant women and 77 percent of their partners surveyed in 2009-10 wanted to know the sex of the fetus. That study also found that most prospective parents didn’t have a sex preference (86 percent of women and 82 percent of partners said they didn’t care either way), and most had picked out a name for both a boy and a girl. But that questionnaire was completed by only 210 pregnant women, all of whom had been referred for prenatal diagnosis to exclude Down syndrome, which could make these results less applicable to a broader population.

The polling company Gallup surveyed 1,014 U.S. adults on this topic in 2007. Gallup found that 47 percent of respondents said they would want to know the sex of a baby before it was born, and 51 percent wouldn’t want to know. But those results probably aren’t great in terms of accuracy — the respondents weren’t necessarily expecting a baby, they were presented with a hypothetical scenario: “suppose that you just found out you were having a baby … .”

Most of the research I’ve described so far is about the United States, but I reckon parental preferences are likely influenced by culture and therefore vary from country to country. The best study I can find that relates to your native France suggests that the geographic differences are huge. According to ELFE (a longitudinal French study that follows 18,000 children), nine out of 10 French parents decide to find out the sex of the fetus. And unlike the American couples in the study I mentioned earlier, 40 percent of parents in France say they do have a preference about the sex of the baby. All of which suggests that you and your wife’s current inclination is all the more unusual.

Hope the numbers help,

Mona

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