A Short History of the ‘Biological Clock’: It’s Been Ticking Off Women for 40 Years

Can we let the term slide into history's dustbins? Maybe ... if we had less media scaremongering and more rigorous science.

So, while fertility, female and male, does decline as we age, the hands on the metaphorical clock aren't ticking away quite as frantically as we have been led to think. Shutterstock

All women want babies, and career women are unhappy with their “liberation” if it puts their traditional role of motherhood at risk.

This was the message of “The Clock is Ticking for the Career Woman,” a March 16, 1978, Washington Post article that popularized the concept of the biological clock. The author was Richard Cohen, who is still a columnist with that paper (despite allegations of bullying and possible sexual harassment of a young female aide in the late 1990s and controversial racial remarks in more recent pieces).

Cohen opened the piece with a description of “Composite Woman.” Her age is “something between 27 and 35” and as if reducing the individual experiences of half of the world’s population into one person wasn’t bad enough, he added: “She’s the pretty one .… Nice figure.” Her job is “wonderful,” and there’s a man in her life.

But everything is not wonderful. She looks down and after Cohen assures her that she can talk to him privately, Composite Woman says, “I want to have a baby.”

Cohen claims to have gone “around, a busy-bee of a reporter, from woman to woman” and found the same stomach-churning anxiety they all felt about the possibility they might not have children.

The best thing to do with such a piece of writing is to let it slide backward into the dustbin of history, and let it be forgotten. That we could probably do, if not for the fact that it was in this deeply problematic article that the term “biological clock” was born.

It’s important to consider Cohen’s piece in context. As Susan Faludi argued in her book Backlash: The Undeclared War Against American Women, two things have frequently triggered backlashes against women’s rights: economic independence and increased control over our fertility. The 1970s seemed to be bringing both. While U.S. women have always worked, the 1970s brought a massive surge of women entering professional and management jobs. Between 1972 and 1985, the number of management roles occupied by women almost doubled, and the landmark abortion case Roe v. Wade happened in 1973.

A conservative section of society didn’t like these changes, and a subtle but strong backlash took root. The backlash’s message was dressed up as concern for unhappy women, women unable to cope with stress, and female movie characters who found “fulfillment” only by giving up their careers. But it really came down to “get back into the kitchen.” And Cohen’s article, whether he intended it as an act of misogyny or was simply carried along by the prevailing narrative, nicely fit that theme.

Nearly 40 years later, we still can’t get away from the biological clock. It persists even though there’s actually relatively little good research about this countdown that supposedly so saddened Composite Woman.

Possibly the best known, or at least the most quoted scientific study on female age and fertility is one published in 2004, which suggested women older than 35 would struggle to conceive. This study examined French birth records from 1670 to 1830 and found that fewer live births were recorded for older women compared to younger. As a biomedical researcher, I often view historical population health data as irrelevant to modern life. While this type of study can be very useful in identifying trends and problems, more rigorous lab-based research is needed to delve into the biology and confidently identify the cause of that problem.

Not to be crude, but unless the authors (demographer Henri Leridon and his team) built a time machine, they couldn’t possibly have known how “active” these couples were. Unless they dug up scores of skeletons, I don’t see how they could even have begun to unravel the answer to what actually caused this supposed infertility. Furthermore, to assume it was the aging woman, and never the aging man, who caused a drop in historical fertility is more speculation than science. The exact cause of contemporary infertility can’t be determined in 20 percent to 30 percent of cases, but among the cases where it can be identified, the issue lies with solely or partly with the male partner about 40 percent of the time.

Of the surprisingly few published studies into fertility in modern women I could find in medical literature, many are based on small samples drawn exclusively from fertility clinics. One 2016 study describes the “inability of women to reduce their desire for a child” based on just 23 women, attending fertility clinics—hardly a random, unbiased sample. A Danish study, which examined attitudes of childless women to family formation, followed just 20 women receiving fertility treatment and drew conclusions about “women” rather than the population it actually studied, women heavily invested in trying to conceive.

Well-designed studies on modern women have shown that fertility is not considerably different between women in their 20s and their 30s. One European study found that with sex twice a week, 82 percent of women ages 35 to 39 conceive within a year. For women aged 27 to 34, the figure was 86 percent, according to recent research. Another Danish study, which studied almost 3,000 women seeking to get pregnant, found that 78 percent of 35- to 40-year-olds got pregnant within a year, compared with 84 percent of 20-to-34-year-olds.

So, while fertility, female and male, does decline as we age, the hands on the metaphorical clock aren’t ticking away quite as frantically as we have been led to think.

A substantial portion of the blame for this misconception must go to the mainstream media. After all, a journalist created the notion of the biological clock, and more contemporary media have kept it going. In 2015, Vogue ran a feature on a 35-year-old single woman who chose to freeze her eggs because “she knew she was coming dangerously close to the age when eligible men might search her eyes for desperation, that unseemly my-clock-is-ticking vibe.” Less over-the-top, and arguably more harmful for it, was another article about how, with the average age of having a first child rising to 30, Australian women were being “warned” to have children earlier. But the expert quoted in that same piece was quoted as saying the best time to have a child was between 20 and 35. So what’s the problem?

We now hear more than we used to the voices of women who don’t want children, but we rarely hear stories of successful conceptions at older ages or of women who were glad they waited. The term “geriatric pregnancy” is still used for expectant mothers older than 35 even though the medical establishment has moved to kinder, less misleading language, and many women understandably find the term offensive.

Without downplaying that older pregnancies are associated with increased risks of complications during pregnancy and chances of genetic abnormalities in babies, these risks are perhaps overstated. For example, a woman in her 20s has a risk of less than 1 in 1,000 of having a baby with Down syndrome. At 40, that risk is 1 percent—a steep increase but still small overall. A British support/resource site for older mothers acknowledges there are some increased risks, but also states that “older mums tend to be better educated, more financially stable, confident, and settled in themselves.”

Fertility also declines in men with age, and older fathers are similarly associated with increased risk of genetic and/or developmental difficulties in children. Yet we hear about this relatively rarely, just as we rarely read about “career men” who “left it too late” and regret their childless state.

Another reason that the “clock” may have started ticking over in our heads is that as women began careers, many of them were still faced with a “second shift”; they still had to do almost as much, if not more, household work and child-care work as they had before their careers. Household labor may not be solely “women’s work” anymore, but things have not changed so much that the burden of domestic and child care is evenly spread. The Economist last year reported that modern stay-at-home dads do far less child care and housework than modern stay-at-home moms. And this cartoon illustrates how many women may end up doing more than their partners simply because it seems less exhausting than to be a household manager, constantly drawing up and delegating tasks.

Clocks are a constant in our lives, and many of us are often racing against them. So the idea that having babies is something else we need to race to do “on time” is logical.

Cohen, in his infamous 1978 piece, declared “This [need to have a child before it’s too late] is where [women’s] liberation ends.” When he was asked about it almost 40 years on, he stood by it—“I don’t have a problem with the piece”—but acknowledges that he wouldn’t be allowed to publish the piece, written as it was, today.

So maybe it’s time we replace the biological clock with discussions about age and fertility that are more nuanced and backed up by modern evidence.