Who knew that the intractable global problems of “overpopulation,” poverty, carbon emissions, climate change, deforestation, civil wars, unplanned pregnancies, and abortions could all be solved by the simple expedient of more birth control? Nicholas Kristof, for one.

He proposed this solution in a New York Times column that will likely be studied by journalism students for decades—as an example of what happens when the last Fact Checker at a “newspaper of record” is asleep on the job.

It took only a 30-second Google search to demolish Kristof’s principal thesis—that the birth of the world’s 7 billionth person is the result of too much unprotected sex that contributes to all these ills.

The 30-second search confirms that population growth is not fueled by an excess of babies, as Kristof contends; it is fueled by more folks living longer than ever. The demographic evidence comes straight from the United Nations Population Division (UNPD). Using UNPD data, a Population Reference Bureau demographer compared population trends in the 0-4 age group and the 65-and-over age group. For simplicity, I’ll refer to these groups as Toddlers and Elders. Here’s what the UN’s data show.

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In 1950 there were 335 million Toddlers worldwide and only 131 million Elders. Due to very low birthrates in developed countries and declining birthrates in most developing countries, today Elders are rapidly closing the gap. After Toddlers peak at about 650 million, sometime between 2015 and 2020, “for the first time in history, the [number of Toddlers] will decline” while Elders keep growing in number, reaching 714 million in 2020. By 2050, there will be 2.5 times more Elders than Toddlers—a complete reversal of the 1950 demographics.

Greater longevity is a good thing—the result of scientific and technological breakthroughs in agriculture and nutrition, in medicine, in water purification, and in improved sanitation.

But it’s the Toddlers on whom the future of humanity depends. When they reach adulthood, they will join the workforce, contributing to the nation’s wealth and tax revenues for roughly four decades, revenues sorely needed to fund Social Security and Medicare. It’s the cohort of former Toddlers who’ll be buying the cars, homes, and pricey electronics that keep an economy humming.

It is only right to provide a safety net for the elderly poor, from pure compassion, as well as in recognition of their contributions and sacrifices. But countries in the European Union are already reeling from the crisis of having too few workers to sustain the cradle-to-grave welfare state, even as the number of retirees explodes. Demographically, America is not far behind.

A good Fact Checker might also have questioned Mr. Kristof’s faith in the theoretical modeling exercises of the Guttmacher Institute, which purport to show that an X increase in access to and use of contraception will reduce unplanned pregnancies by Y, and abortions by Z.

The evidence simply doesn’t back this up. Empirical data of the last fifty years overwhelmingly show that with increased access to and use of contraception, unplanned pregnancies and abortions very often rise, or at best, stay about the same (an exception being found among women in former Soviet bloc countries, whose lifetime abortions often numbered well into double digits). Guttmacher and others have published numerous papers describing this apparent paradox.

Spain provides a recent example of this phenomenon: Between 1997 and 2007, contraceptive use among women rose 63 percent, while the rate of elective abortion in Spain more than doubled (108 percent).

In Sweden, teen abortion rates dropped 40 percent between 1975 and 1985, and teen childbearing also fell. Later the government increased pregnancy prevention efforts—providing free contraceptive counseling, subsidized oral contraceptives (OCs) and condoms, and over-the-counter emergency contraceptives. Between 1995 and 2001, teen abortion rates in Sweden increased by almost one-third—from 17 to 22.5 per 1000.

Duke University economics professor Peter Arcidiacono writes: “Our results suggest that increasing access to contraception may actually increase long run pregnancy rates. … On the other hand, policies that decrease access to contraception, and hence sexual activity, may lower pregnancy rates in the long run.”

Key studies with full citations are summarized in a fact sheet titled “Greater Access to Contraception Does Not Reduce Abortions.”

Why do contraceptives fail to live up to their name and their advertising? Many factors contribute to lack of effectiveness in preventing pregnancies (and STDs), especially among teens: method and user errors, the phenomenon of “risk compensation,” age-related fertility, and frequency of intercourse. Guttmacher’s Family Planning Perspectives reports the following 12-month pregnancy rates for sexually active OC users: 3.3 percent for middle-income married women age 30 and above; 13 percent for low-income single teens; and 48.4 percent for low-income cohabiting teens.

Among sexually active women whose partners use condoms as their primary method of birth control, 12-month pregnancy rates are as follows: 6.2 percent for middle-income married women age 30 and above; 23.2 percent for low-income single teens; and 72 percent for low-income cohabiting teens.

If it were just a matter of hormonal birth control not being 100-percent foolproof, and putting aside the moral questions involved in casual and contraceptive sex, some might argue for its use by disciplined, meticulous adults, in a stable relationship, willing and financially able to raise the potential “unplanned” baby.

Hormonal contraceptives are not benign, however, as any Fact Checker would learn from drug labels on the FDA’s website (even without perusing the voluminous Adverse Events data).

The link between hormonal contraceptives and breast cancer has been known for over thirty years. The World Health Organization (WHO) classifies the synthetic estrogen and progestin in contraceptives as carcinogenic to humans. The largest metanalysis (54 studies with over 150,000 women) found that women who use OCs before age 20 have almost double the risk of developing breast cancer before age 30, compared to women who did not use OCs as teens.

Until 2002, hormone replacement therapy (HRT), using hormones similar to those in combined OCs, but in lower doses, was standard treatment for menopausal symptoms. As HRT use increased, breast cancer rates rose by over 40 percent from the early 1980s through 2001. In 2002, the Women’s Health Initiative HRT trials were abruptly halted due to findings of increased risks of breast cancer, heart disease, blood clots, and stroke. As prescriptions plummeted, breast cancer rates in women over age 50 dropped 8.6 percent between 2001 and 2004. WHO now classifies HRT as carcinogenic in humans.

A Fact Checker could have told Mr. Kristof that there is, in fact, a way to slightly reduce population growth through contraceptive use, but not what he had in mind: Contraceptives can kill adults and teens.

In addition to having an increased risk of dying from breast cancer, women using hormonal contraceptives and their partners are dying at higher rates from incurable STDs, like HIV/AIDS, because hormonal contraceptives can double the risk of STD acquisition.

Women continue to die from high levels of synthetic hormones. For example, about 130 deaths have been linked to the Ortho Evra patch from blood clots resulting in heart attack, stroke, or pulmonary embolism.

Three new studies show a higher risk of lethal blood clots or gallbladder disease in women using birth control pills like Yaz. The manufacturer, Bayer, is already facing “6,850 lawsuits alleging that Yaz’s drospirenone ingredient is more dangerous than those used in competing pills. About from heart attack, stroke or pulmonary embolism have been associated with Yaz and similar pills.”

The manufacturer of NuvaRing® now faces 730 lawsuits in the U.S. for blood clot-related injuries and deaths associated with its use. About 40 deaths linked to NuvaRing® use have been identified to date in the FDA adverse event database.

A good Fact Checker could have given Mr. Kristof these hard truths and spared him from looking foolish. But where are all the good Fact Checkers when you need them? Not at The New York Times.