Their Mothers Were Teenagers. They Didn’t Want That for Themselves.

JENNINGS, Mo. — Brittnee Marsaw was born to a 15-year-old mother in St. Louis and raised by a grandmother who had given birth even younger. Half grown by the time her mother could support her, Ms. Marsaw joined her three states away but never found the bond she sought and calls the teen births of preceding generations “the family curse.”

Ana Alvarez was born in Guatemala to a teenage mother so poor and besieged that she gave her young daughter to a stranger, only to snatch her back. Soon her mother left to seek work in the United States, and after years of futilely awaiting her return Ms. Alvarez made the same risky trip, becoming an undocumented teenager in Washington, D.C., to reunite with the mother she scarcely knew.

While their experiences diverge, Ms. Marsaw and Ms. Alvarez share a telling trait. Stung by the struggles of their teenage mothers, both made unusually self-conscious vows not to become teen mothers themselves. And both say that delaying motherhood gave them — and now their children — a greater chance of success.

Their decisions highlight profound changes in two related forces that shape how opportunity is conveyed or impeded from one generation to the next. Teen births have fallen by more than three-quarters in the last three decades, a change of such improbable magnitude that experts struggle to fully explain it. Child poverty also plunged, raising a complex question: Does cutting teen births reduce child poverty, or does cutting child poverty reduce teen births?

While both may be true, it is not clear which dominates. One theory holds that reducing teen births lowers child poverty by allowing women to finish school, start careers and form mature relationships, raising their income before they raise children. Another says progress runs the other way: Cutting child poverty reduces teen births, since teenagers who see opportunity have motives to avoid getting pregnant.

Ms. Marsaw, who waited until 24 to have a child — a daughter, Zaharii — has considered the issue at length and embraces both views.

“This is a very, very, very good topic — it touches home with me in so many ways!” she said, adding that teen pregnancy and child poverty reinforce each other. “If you escape one, you have a better chance of escaping the other.”

Teen births have fallen by 77 percent since 1991, and among young teens the decline is even greater, 85 percent, according to an analysis by Child Trends, a research group that studies children’s well-being. Births have fallen at roughly equal rates among teenagers who are white, Hispanic and Black, and they have fallen by more than half in every state.

The decline is accelerating: Teen births fell 20 percent in the 1990s, 28 percent in the 2000s and 55 percent in the 2010s. Three decades ago, a quarter of 15-year-old girls became mothers before turning 20, according to Child Trends estimates, including nearly half of those who were Black or Hispanic. Today, just 6 percent of 15-year-old girls become teen mothers.

“These are dramatic declines — impressive, surprising, and good for both teenagers and the children they eventually have,” said Elizabeth Wildsmith, a Child Trends researcher who did the analysis with a colleague, Jennifer Manlove.

Not all teen mothers are poor, of course, and many who do experience poverty escape it.

The reasons teen births have fallen are only partly understood. Contraceptive use has grown and shifted to more reliable methods, and adolescent sex has declined. Civic campaigns, welfare restrictions and messaging from popular culture may have played roles.

But with progress so broad and sustained, many researchers argue the change reflects something more fundamental: a growing sense of possibility among disadvantaged young women, whose earnings and education have grown faster than their male counterparts.

“They’re going to school and seeing new career paths open,” said Melissa S. Kearney, an economist at the University of Maryland. “Whether they are excited about their own opportunities or feel that unreliable male partners leave them no choice, it leads them in the same direction — not becoming a young mother.”

Mindful of their mothers’ struggles, Ms. Marsaw, 29, and Ms. Alvarez, 34, each offer a study of why teen births are falling and how the decline might affect upward mobility. One woman found that it brought the prosperity she had sought. One hopes it still will.

A Path to College

Ms. Alvarez felt left behind even before her mother left Guatemala. Nineteen and single when she had her second child, her mother left the family farm to work in the city, and their contact shrank to monthly visits.

After her mother had more children, a woman she met in a clinic waiting room offered to adopt one. Ms. Alvarez was equally surprised first to be given away and then to be reclaimed months later. Then her mother departed for Washington, and Ms. Alvarez came to think of a mother as “something I hoped that someday I will have.”

She quit school after fourth grade to help her grandfather care for her younger siblings. For her 15th birthday, she asked her mother to hire a smuggler to bring her north.

The reunion disappointed. To Ms. Alvarez’s surprise, her mother was married and had another child. She seemed distant, stern and impatient with questions about why she had left. “I had more resentment than I understood,” Ms. Alvarez said.

While Ms. Alvarez did not find reconciliation, she did find opportunity. Starting high school as an undocumented Spanish-speaking migrant with a fourth-grade education, she was a better student than she knew. A counselor at a Washington clinic, Mary’s Center, said she could earn a college scholarship.

Looking no further than her mother’s life, she saw a threat. “I realized if I get pregnant, I’m not going to college,” she said.

It was one thing to set her goal, another to sustain it though a precarious adolescence. Of the two ways to avoid pregnancy, Ms. Alvarez judged abstinence more certain than contraception and ignored girls who teased her for avoiding sex.

In her junior year, a suitor named Fredy who worked as a cook asked her to move in. He was seven years older, fun and supportive, and she needed a place to stay, having left her mother’s apartment for a rented room. But she forced herself to stop taking his calls. She graduated from high school at 20 with the college scholarship — neither a teen nor a parent.

“Wow, I made it all the way to college!” she told herself.

Ms. Marsaw may be even more inclined to see her life through the prism of adolescent pregnancy. Her grandmother raised her on a food stamp budget in a house with a dozen aunts, uncles and cousins, while her mother, who had given birth at 15, came and went and finished her teens with a second child.

When Ms. Marsaw let slip in third grade that her mother had a different address, she was transferred to a distant school, and care fell to a rotating cast of relatives. She came to think of her mother as “a person I needed that I couldn’t reach.”

Her mother moved to Atlanta to work as a medical technician. Ms. Marsaw followed but felt frustrated by her mother’s long hours and emotional remove. Where others might see a parent striving to get ahead, Ms. Marsaw felt a new way of being left behind. “The reason I’m a fast talker is because I wanted to get my point across before she walked out for her 16-hour shift,” she said.

She identified the cause of her mother’s struggles — teen motherhood — and pledged to avoid it. In 10th grade, she insisted that her boyfriend use condoms. In 11th grade, she stopped dating. Classmates taunted her, but loner status was a price she was willing to pay. “I did what it took not to have children,” she said.

She returned to Missouri for her senior year and wrote herself a letter years later, celebrating what she achieved: “U finished high school w/no children so pat yourself on the back.”

‘Greater Confidence’

On the surface, the decline in teen births is easy to explain: Contraception rose, and sex fell.

The share of female teens who did not use birth control the last time they had sex dropped by more than a third over the last decade, according to an analysis of government surveys by the Guttmacher Institute. The share using the most effective form, long-acting reversible contraception (delivered through an intrauterine device or arm implant), rose fivefold to 15 percent. The use of emergency contraception also rose.

Contraception use has grown in part because it is easier to get, with the 2010 Affordable Care Act requiring insurance plans, including Medicaid, to provide it for free.

At the same time, the share of high school students who say they have had sexual intercourse has fallen 29 percent since 1991, Child Trends found. Some analysts, including Brad Wilcox, a sociologist at the University of Virginia, say the postponement of sex, which has intensified since 2013, stems in part from the time teens spend in front of screens.

Abortion does not appear to have driven the decline in teen births. As a share of teenage pregnancy, it has remained steady over the past decade, although the data, from the Centers for Disease Control and Prevention, omits medication abortions, and analysts say the recent Supreme Court decision in Dobbs v. Jackson Women’s Health Organization, eliminating the constitutional right to abortion, could cause teen births to rise.

If adolescent girls are more cautious with sex and birth control, what explains the caution? A common answer is that more feel they have something to lose. “There is just a greater confidence among young women that they have educational and professional opportunities,” Mr. Wilcox said.

In 2013, the economists David Autor and Melanie Wasserman found that women in their mid-30s were nearly 25 percent more likely than men to have a four-year college degree, and at every educational level earnings had grown faster for women than men.

With teen births and child poverty falling in tandem, the chicken-egg question that follows, is which caused which?

It may seem intuitive that postponing motherhood helps teens escape poverty. But some researchers say the opposite dynamic drives change: Cutting child poverty reduces teen births. They cite studies that have found that most adolescents who become teen mothers are so disadvantaged their prospects would not improve even if they postponed childbirth.

The studies compared women who gave birth as teens with those from similar backgrounds who avoided teen birth (in some cases sisters), and found the groups fared similarly as adults.

“Research has shown that among those who grow up in disadvantaged circumstances teen childbearing has little independent effect on economic outcomes,” said Ms. Wildsmith, the Child Trends analyst.

Skeptics see limits in the data and note that the payoff to education is growing.

“I strongly disagree with the argument that teen births have no effect on social mobility,” said Isabel V. Sawhill of the Brookings Institution. “It’s a lot easier to move out of poverty if you’re not responsible for a child in your teenage years.”

The debate is more than academic. Some progressives worry that a narrow focus on preventing teen births will undermine broader anti-poverty plans and risks blaming adolescents for their poverty. Other see reducing poverty and teen births as complementary causes meant not to blame young women but empower them.

Achieving a Dream

As a test of whether postponing birth reduces poverty, Ms. Marsaw’s life yields ambiguous conclusions. Even without a child, her transition to adulthood proved difficult. She was slowed by an immobilizing bout of depression, which she blamed in part on her childhood separations from her mother.

“Forgive ur mom,” she later wrote to herself. “She was so young.”

In her early 20s, she followed her mother to Texas, got a job at an indoor amusement park and dated a man who parked cars. For all her teenage vigilance, she stopped using contraception, figuring “if happens, it won’t be a crisis.”

She gave birth at 24, nearly nine years later than her mother.

Hardship followed nonetheless. Her depression returned and her relationship ended. Unable to pay the rent alone, she returned to St. Louis. She and Zaharii, 5, have lived in at least seven places — eight, counting times when they slept in a car — though Ms. Marsaw is proud that unlike her mother she never left her daughter in someone else’s care. As an anti-poverty strategy, postponing motherhood was not foolproof.

Still, Ms. Marsaw sees benefits to the wait. She is more “emotionally intelligent” as a parent, she said, more savvy about jobs, and more resilient. She also said an earlier start might have left her with a second child before she was ready.

Last year she got a commercial driver’s license and spent months as a cross-country trucker, with Zaharii sharing the cab. She is driving a child care van for the winter, and with an income of about $40,000 she managed to buy a small house. Her mother sometimes helps, and their relationship has improved, with Ms. Marsaw more sympathetic to the sacrifices she made to advance.

“I don’t feel as though I have completely accomplished who I am or where I want to be,” she said. “But I’m no longer in poverty.”

For Ms. Alvarez, the story is simpler: Her future unfolded as planned. Though still working on her English, she managed the transition to the University of the District of Columbia. In her second year, fortune smiled: She boarded a city bus and ran into Fredy, the man who had pursued her in high school.

Like Ms. Marsaw, she no longer feared pregnancy as she had in her teens. When a lapse in contraceptive use had a predictable effect, the news solidified her plans more than it disrupted them. She married shortly before giving birth at 23. “You’ve never ready to become a mother, but I felt like I can do this,” she said.

A baby did slow her educational progress. Working two jobs, she took six years to earn a bachelor’s degree, then started a job at Mary’s Center, the clinic that had encouraged her to seek scholarships.

She coordinates care for cancer patients and has legal protection under Deferred Action for Childhood Arrivals, a program for undocumented migrants who came to the United States as youths. With a family income above the national average, she and her husband recently bought their first house.

“If I die tomorrow, I can say I achieved the American dream,” Ms. Alvarez said. “But if I had gotten pregnant as a teenager? I’m not sure, but I don’t think so.”