Trump and Bobby Jr. messages on declining birth rates has racist undertones
By Joshua Cohen
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| Musk says what RFK Jr. and Trump imply |
Kennedy issued a warning at a White House press briefing in October, arguing that the fertility rate is not high enough to ensure the American population remains stable. The rate dropped to a historic low in 2023 and continued to slide in 2024. The total fertility rate that year was less than 1.6 live births per woman of childbearing age. This is well below the replacement rate of 2.1, at which population size remains constant from generation to generation.
Many women are proactively choosing to have no or fewer children. But for those who do wish to get pregnant, yet struggle with infertility, President Trump has announced that he will work with a drugmaker to offer several fertility medications at a heavy discount and make it easier for employers to offer fertility benefits.
The administration has not, however, spoken publicly about specific treatments geared toward men. And until recently, the topic of male infertility was somewhat taboo, even though it plays a role in roughly half of all cases in which a woman struggles to get pregnant.
But what role does male biology play in declining birth rates? Could addressing this help the administration meet its fertility-boosting goals? The answer, it turns out, is complicated.
Over the years, researchers have asked if sperm counts really are on the decline. More recently, one group developed what some critics now call the “sperm count decline hypothesis,” which posits that sperm counts are falling and that a low sperm count is an indicator of sub-optimal health, which could impact fertility.
A 2017 meta-analysis, for example, based on data from North America, Europe, Australia, and New Zealand, found that sperm count had declined by 52 percent between 1973 and 2011. A follow-up in 2022 by some of the same authors showed a similar reduction across an even wider range of countries. Rossella Cannarella, a clinician and researcher at Italy’s University of Catania who was not involved in either study, told Undark that the findings track with the results of her own research and with what she sees in patients in her clinical practice. She attributes the lessening in sperm count to pollution and metabolic disorders such as obesity, among other things.
In a newly released report for the Health and Environment Alliance, an EU-based not-for-profit, Cannarella warns of the dangers of chemical pollution in fueling a “growing male health crisis.” This includes male infertility — with evidence suggesting a possible association with exposure to harmful chemicals and other so-called endocrine disruptors. These are natural or synthetic substances found in plastics, food packaging, and pesticides that can interfere with hormones such as estrogen, testosterone, and thyroid. Notably, at that October White House press briefing, Kennedy emphasized the possible role of endocrine disruptors in the fertility rate decline.
Endocrine disruption is posited to take place through exposure to substances in the air, food, and water, as well as through the skin. Endocrine disruptors in food can impact the beneficial microbes living in a person’s gut. Germar Pinggera, a clinician and researcher at the Innsbruck Medical University, told Undark that pollution, poor diet, and an imbalanced microbiome can be detrimental to sperm production, as well as sperm quality. These factors, he suggests, may all be affecting fertility.
At the same time, Pinggera said that while some studies point to a decrease in sperm count, “there are still other data that aren’t confirming that.”
In a press release, the lead author of a recent meta-analysis suggested that among men in the U.S. with no known fertility challenges, “sperm counts are largely stable and haven't changed significantly” in recent years. Moreover, it’s unclear whether sperm quality has declined. According to a 2022 review published in Nature Reviews Urology, researchers have observed a trend in some geographic areas, but available data doesn’t indicate that semen quality is necessarily deteriorating worldwide or in the Western world.
EDITOR'S NOTE: Here's what the Cleveland Clinic said:
Sperm counts haven’t declined among American men in recent years, new research from Cleveland Clinic finds.
Several high-profile papers had suggested that sperm counts have drastically fallen globally over the past few decades. In contrast, the new data suggests that’s not the case, at least among men in the United States without known infertility.
“We found that at least in men with no known fertility challenges, sperm counts are largely stable and haven't changed significantly in the last few years, which is reassuring news. It doesn't necessarily mean that sperm counts among infertile men aren't worsening, but it does mean that for the average man, there's no cause for panic,” says lead investigator Scott D. Lundy, MD, PhD, Urology Program Director at Cleveland Clinic.
A closer look at the data
Dr. Lundy, along with colleagues from two other institutions, performed a systematic review and meta-analysis of studies published between 1970 and 2023, of U.S. men without known infertility, confirmed or not. A total of 58 articles met inclusion criteria, representing 75 unique studies of sperm concentration estimates in a total of 11,787 men. Of the 75 estimates, 51 were of populations of men with unknown fertility status, while the other 24 were of men confirmed to be fertile.
No changes in sperm concentrations were seen across the study populations over the 53-year period (P = 0.42), with similar results after adjustment for U.S. census region.
Some cause for reassurance
This was somewhat surprising, Dr. Lundy says. “We expected to find a subtle decrease over time, not a drastic decrease. I think finding nothing at all was a little bit surprising, and it certainly does not mean that we can ignore this issue or not study this further. But in this case, I think there's at least some evidence to suggest that we can be somewhat reassured.”
There was a slight decline, of -0.35million/mL per year, after adjustment for both census region and fertility status (P=0.04). However, among the 49 studies that reported sufficient data to determine total mean sperm count, there was actually a significant increase of 2.9 million per year between 1970 and 2018 (P = 0.03).
And, when stratified by fertility status, there were no significant changes in sperm count among the fertile men (P = 0.26) or those with unknown fertility status (P=0.06).
“There was a very modest decline when we did an aggressive correction, but I think in the grand scheme of this study where no other factors were significant, I'm less inclined to put a great deal of weight in that. And in fact, the mean concentration increased before the before the correction was applied, which suggests to me that this is likely a statistical anomaly, or at least certainly not a catastrophic decline,” Dr. Lundy says.
This study does not address whether infertility is on the rise. “We didn't track men who were fertile who became infertile. I think based upon the literature so far, that might be the case due to obesity or environmental exposures, and more research is needed to definitively answer that question. But in our population here, despite prior reports to that that received a great deal of press and concern, there is some cause for reassurance.”
Furthermore, a reevaluation of the 2017 meta-analysis cited above suggests there could be issues with respect to how sperm counts were measured. Researchers identified inconsistencies in the sperm count decline hypothesis and proposed an alternative framework that asserts that sperm count varies within a wide range, much of which can be considered normal.
Critics of the sperm count decline hypothesis also contend that it takes for granted that sperm count is an accurate predictor of male fertility. Experts disagree about what exactly the fertility implications are of a reduced sperm count. Male fertility involves multiple components, including sperm count, concentration, shape, and motility, in addition to testosterone levels, age, and other characteristics. And male fertility can’t be seen independently from female fertility, say, in the context of a couple trying to conceive spontaneously or with assistive reproductive technologies. Here, it’s essential to evaluate the interactions between sperm, the female reproductive tract, and the egg.
What about the role of testosterone, the hormone responsible for changes that occur in boys during puberty, including production of sperm and the maintenance of certain biological functions related to reproduction in adult men? Levels of testosterone generally peak during adolescence and early adulthood. As a male ages, his testosterone level gradually diminishes — typically around 1 percent annually after age 30 or 40.
Testosterone is essential for sperm production, but it isn’t the only necessary ingredient. Other hormones are also involved, including luteinizing hormone — which stimulates testosterone production — and follicle-stimulating hormone, making it difficult to parse the precise role each hormone plays in infertility.
And while Kennedy has asserted that young men’s testosterone levels have plummeted over the decades, the scientific literature tells a more nuanced story. A 2021 publication, for example, found that testosterone levels have diminished among young adult males from 1999 to 2016 by around 25 percent. Further, researchers observed that among adolescent and young adult males, testosterone deficiency is 20 percent.
Still, Geoff Werstuck, a professor at McMaster University in Ontario, wrote in an email to Undark that the “relative speed of the decline is absolutely noteworthy.” An endocrinologist from the Cleveland Clinic also pointed to the accelerated decline in testosterone and appeared to link it to a similar set of elements likely causing a reduction in sperm count.
But not everyone agrees about the extent of the decline. Adith Arun, a researcher at the Center for Outcomes Research and Evaluation at Yale New Haven Hospital, wrote in an email to Undark that a shift occurred over time in terms of measurement techniques that makes it hard to make firm comparisons. The cutoff for low total testosterone was not updated to account for use of these new techniques. In a follow-up email, he noted that this may in turn “result in overstating the fraction of self-reported healthy individuals with low total testosterone values.”
And Werstuck noted that “because of a lack of good historical data” it’s difficult to determine when the testosterone downturn began and “precisely how large the effect is.” He also said that he doesn't believe there is "strong data to support or discount" the various factors that have been hypothesized as causing the trend.
All of this means that the exact role of male biology in declining birth rates is unclear.
At a discussion in August organized by the Harvard University T.H. Chan School of Public Health, one panelist said that much of the decline comes from teenagers and young women delaying childbearing. The expert, Margaret McConnell — an associate professor of in the Department of Global Health and Population at Harvard University — cautioned that aggregate family size over a woman’s lifetime has not fallen nearly as pointedly as the annual fertility rate.
“We're seeing this as part of an ongoing process of fertility delay” Leslie Root, a fertility and population policy researcher at the University of Colorado Boulder, told Newsweek. “We know that the U.S. population is still growing, and we still have a natural increase — more births than deaths.”
The “ongoing process of fertility delay” that Root refers to may partially reflect reproductive agency. Women can make informed decisions about their reproduction that in turn depend on a host of factors that include their career paths, ability to afford raising a family, and technological advances such as IVF and egg-freezing. These can influence the age at which individuals marry, preferences regarding family size, and the general reproductive behaviors in women and men in American society.
And so, despite the panicked rhetoric about fertility and sperm counts, there remain a host of unresolved questions, many of which extend beyond the realm of science into social factors.
This article was originally published on Undark. Read the original article.
