Births and pregnancies in the United States have been on a long-term decline. A new data analysis provides one reason: It’s becoming less common for women to get pregnant when they don’t want to be.
The analysis, released Thursday in the journal Demography by researchers at the Guttmacher Institute, estimates the number of pregnancies in the United States — there is no single official count — and examines women’s feelings about the timing of their pregnancies. In the past, most demography surveys have asked if pregnancies were intended or not, but that approach missed nuances like whether a woman was ambivalent about being pregnant — or wanted to be pregnant, but earlier or later.
The new analysis, covering 2009 to 2015, found that a growing majority of women said their pregnancies came at the right time. It uncovered a decline in the share of pregnancies that women didn’t want or that happened too soon, a shift driven by young women.
It also found that a significant and increasing share of women — particularly those 35 and older — said they were getting pregnant later than they wanted.
“This just bolsters that idea that people have more control over their reproduction, especially in earlier ages,” said Alison Gemmill, a demographer and epidemiologist at Johns Hopkins who studies reproductive health and was not involved in the new study.
It also reflects, she said, “a change in people’s ideals about when to have kids and norms around the ideal time — when we’re settled, when I have my career established.”
The new data is one of the clearest indicators that the drop in fertility during the Great Recession was not just a temporary delay, as often happens in recessions. Instead, it seems to have coincided with a broader shift in what women wanted, and increased access to contraception.
The analysis combined reports and surveys from the National Center for Health Statistics; abortion data from Guttmacher; and estimates of total pregnancies and miscarriages.
The data is from before two seismic events that affected fertility: the pandemic, followed by the Dobbs decision that ended the nationwide right to abortion. It’s unclear what long-term changes those will bring. There is early evidence that at the beginning of the pandemic, many people delayed getting pregnant. There could also be an increase in the share of unwanted or mistimed births in states with new abortion bans.
The United States has long had one of the highest rates of unintended pregnancy in the industrialized world. It has declined 23 percent in the last three decades, and 46 percent of pregnancies are now unintended. In Western Europe, by comparison, 36 percent are unintended, and the rate has not changed much.
The new analysis suggests that during the period of the study, American women rapidly gained more autonomy over their family planning, and had fewer abortions because of it.
The data indicates that “far fewer individuals were becoming pregnant in 2015 than in 2009, and that abortion incidence went down because individuals did not get pregnant, not because their pregnancies continued to a birth instead of an abortion,” wrote the paper’s authors, the Guttmacher researchers Kathryn Kost, Mia Zolna and Rachel Murro.
In 2015, just under a quarter of women said their pregnancy came too soon, a decline of 18 percent from 2009. There was also a slight decline of 5 percent, to 17 percent, in the share of pregnant women who said they did not want a baby at all. These declines were driven by younger women having significantly fewer unwanted pregnancies.
During this period, birth control became more easily accessible, largely because of a provision in the Affordable Care Act requiring it to be free for patients. Research has shown a big increase in the share of women using more effective long-acting reversible contraceptives like IUDs. A program in Colorado to provide free long-acting birth control led to a 40 percent decline in births to teenagers and young adults.
There is also data showing that young people are having less sex, perhaps because they are socializing online more and engaging in fewer risky behaviors overall.
The fertility rate has been increasing among the oldest childbearing women, ages 35 to 44, and in one sense, researchers said, this indicates that women are exercising more control over the timing of their pregnancies. Highly educated women have been delaying pregnancies until they complete their educations and start their careers, and more recently, that has become true of women of all educational backgrounds.
Yet the analysis also shows something new — that for many women over 35, their pregnancies are coming later than they want. The share who said so increased 84 percent, while the share who said they occurred at about the right time dropped 26 percent. (The new data does not include women who never became pregnant.)
This could be because they run into fertility troubles at older ages, the researchers wrote, and suggests a “substantial, and growing, unmet need for fertility treatment services.”
It could also indicate, researchers said, that for some, family planning was driven by financial uncertainty — they may have waited to get pregnant until they found their financial footing but wished it had been earlier. It could suggest that, in hindsight, they regretted having waited. Or it could signal that more women are having difficulty finding suitable partners.
“To see it increasing, we started thinking this isn’t just about difficulty becoming pregnant at an older age,” said Ms. Kost, who has a Ph.D. in sociology and is director of domestic research at Guttmacher. “We are also wondering to what extent is this a reflection of economic constraints and realities people are living through, and the increasing burdens people are feeling in the ability to have families on the timeline they want.”