Whopper of the Week: RFK Jr. Makes Up Spooky Stories about Old Men Being More Virile than Teens

THIS WEEK'S WHOPPER: 

Robert F. Kennedy Jr. Makes Up Spooky Stories about old men being more virile than teens

IN SUMMARY:

American fertility rates, like those of most countries, have been dropping since about 1960 for many reasons related to broad social, economic, technological and demographic changes. At a White House press conference in October, Health and Human Services Secretary Kennedy told Americans that our fertility rate was a national security threat, that teenage boys are less virile than 65-year-old men, and that the root cause of the problem is endocrine disruptors.  But Kennedy’s claims are not fact based: data about sperm count does not even exist for teenage boys and the scientific consensus has long been that the quality of sperm declines as men age. In short, Kennedy tried to tie one of his favorite themes, that chemicals are poisoning our youth, to an insidious right-wing conspiracy theory that dropping fertility rates are leading to a decline in American power.  

WHY IS THIS A WHOPPER?

On October 16, President Trump called a press conference to announce an agreement with a pharmaceutical company that will provide lower-cost fertility drugs and new draft guidelines from the Department of Labor that will facilitate the ability of companies to offer supplemental insurance coverage for infertility. Health and Human Services Secretary Kennedy was among the officials present at the Oval Office event.

When Kennedy spoke, he focused his comments on teenagers, saying, “When my uncle was president, the fertility rate in this country was 3.5 percent. Today, it is 1.6 percent. The replacement rate, in other words the amount of fertility that you need in order to keep your population even, is 2.1 percent. We are below replacement right now."

Kennedy went on to claim, "Today the average teenager in this country has 50 percent of the sperm count, 50 percent of the testosterone as a 65-year-old man. Our girls are hitting puberty six years early, and that’s bad, but also our parents aren’t having children.” The comments were out of place, bizarre, and not the first time Kennedy has made controversial statements about sperm count or fed the public anxiety about masculinity. 

To fact-check some of Kennedy’s outrageous assertions about teen sperm count, Professor Angela Rasmussen reviewed studies on PubMed that included information on “teenage sperm count.” Most of the papers examined the impact of various medical conditions (e.g.  spermatocele, hemorrhoids in the scrotum) or their treatments on fertility. Other studies about sperm involved teenagers who received puberty blockers or hormone therapy in the context of gender transition. Neither sets of studies are broadly representative of healthy teen boys as a demographic group. Rasmussen notes there is simply insufficient data about teen boys to allow anyone to make population-level estimates about teenage boys' sperm counts.

The vast majority of studies about sperm counts are done on populations of adult men. Studies overwhelmingly show that sperm count and sperm volume and motility change over time, peaking in mid-life and declining after age 50. Research starting the 1980s has consistently found that aging is associated with the deterioration of semen quality. Kennedy did cite a review of studies which suggests that average sperm counts may have declined between 1973 and 2011. However, the authors could not break down the data by age groups, so they did not make any claims about differences between teen boys and elderly men. The scienitific debate about declining sperm counts and their effect on fertility is not yet settled. Similarly, the role of endocrine disruption in male and female fertility is an active area of research, but it is unlikely to be the “root cause” of declining birth rates as Kennedy seems to suggest. 

WHY IT MATTERS:

Kennedy expressed concern that “We are below replacement right now” as younger generations are not having enough children to maintain the U.S. population. Without regard for the evidence, Kennedy jumped to a biological explanation for changing fertility rates. In the process, he ignored important social and structural reasons why people are having fewer children, including higher levels of adult education, later marriage rates, access to birth control, the high cost of childcare, the lack of access to healthcare, abortion restrictions that make many women fear pregnancy, lack of maternity and paternity leave and other services necessary for child rearing, and more. 

If Kennedy was really worried about the biological causes of declining fertility, as Health and Human Services Secretary, he could focus his energy on the health issues that cause male fertility problems. For instance, around 30% of pre-teen boys who get mumps orchitis have longer-term fertility problems, which the MMR vaccine prevents. Other vaccine-preventable infections that impact testicular function, semen quality, and fertility include COVID, influenza, hepatitis B, HPV and Ebola. To safeguard America’s reproductive future, as part of a pro-family policy, Kennedy should champion the uptake of preventive vaccines as well as research into the underlying biological causes of infertility.

Kennedy is probably less bothered by infertility than he is by the health and environmental effects of food additives, food coloring, fertilizers, chemicals and endocrine disrupters. The MAHA Commission Report in May 2025 explicitly stated that the administration would “evaluate the threat of certain chemicals and certain other environmental exposure to children.” Kennedy sees the world through the lens of an environmental lawyer who litigates against agro-chemical businesses. That’s why, at a press conference that was meant to give hope to infertile couples, Kennedy fear-mongered about chemicals poisoning our children. In doing so, he misrepresented the science and missed the boat on identifying ways he could truly help our nation address fertility issues. 

Adapted from “Rasmussen Retorts” Substack, "Secretary Kennedy Comes to Teen Sperm Journal Club," by Tara C. Smith, PhD.

Other contributors: Aurora Horstkamp, MD, Erica Bersin, BCPA, Benedicte Callan, PhD.