This is not opinion. This is evidence.

The CDC tracks pregnancy-related deaths through state vital records, and the 2022 release put the national rate at 22.3 per 100,000 live births. To frame what that number means in international terms, Norway recorded zero maternal deaths that year. Sweden was at 5 per 100,000. Switzerland at 1.2.

The US rate sits closer to Iran and Ukraine than to its peer countries. The CDC counts deaths during pregnancy and within 42 days of birth from any cause related to or worsened by the pregnancy, which matches the WHO definition, so the comparison is honest.

One reasonable caveat: the US number partly reflects better tracking after 2018, when every state added a pregnancy checkbox to death certificates. Even adjusting for that, the rate is more than five times Sweden's. The number has been rising while every other rich country has been pushing theirs down.

The Commonwealth Fund is a private healthcare foundation that publishes cross-country health system comparisons. Their 2024 maternal health report ranked the United States last among high-income nations. American mothers die at four to seven times the rate of mothers in Norway, Sweden, the Netherlands, and Japan.

The US spends about 17 percent of GDP on healthcare, the highest in the world, and runs maternal mortality numbers that look closer to countries spending three to four percent. The report breaks deaths down by when they happen. Most US maternal deaths happen postpartum, often weeks after the hospital discharge.

The countries that do better tend to share a few things: universal midwifery, longer postpartum follow-up, and no financial incentive to push mothers out of the hospital fast. The report does not argue for any one policy fix. It just lays out the pattern.

In April 2025, Harvard's news outlet published an analysis of pregnancy-related death trends across high-income nations. Every other wealthy country has been pushing maternal mortality down for decades. The US is the only one moving in the opposite direction. The rate has roughly doubled since 1987.

Most of the increase shows up in hypertensive disorders, cardiovascular events, and overdose deaths, but the deeper system factors behind those proximate causes are what researchers at the Harvard T.H. Chan School of Public Health point to in the piece. Postpartum follow-up is sparse compared with Europe.

Many women lose insurance coverage within two months of giving birth. Rural maternity wards have been closing for over a decade, creating large maternity deserts where the nearest delivery hospital can be over an hour away. The reporting pulls data from the CDC's vital statistics releases.

The OECD publishes annual infant mortality rankings across its 38 member countries. The most recent release puts the United States 33rd out of 38, at 5.1 infant deaths per 1,000 live births.

Sweden sits at 2.1, Norway at 1.6, Japan at 1.8, Iceland and Estonia below 2 as well. The US rate is roughly three times higher than the Scandinavian average. About two-thirds of US infant deaths happen in the first month of life, often from prematurity-related complications.

The US does have a higher preterm birth rate than its peers, which explains part of the gap. But Scandinavian countries with similar preterm rates still produce better outcomes on infant survival, which means the gap is not just about who is being born early. It is about what happens to those babies and their mothers in the months around birth.

The CDC tracks maternal and infant mortality by race using the same vital records that produce the headline national numbers. The disparities are extreme and have been for as long as the data has been collected.

Black women in the US die at 49.5 per 100,000 live births, roughly 2.6 times the rate for white women and nearly 50 times the rate for women in Norway. Black infants die at 10.97 per 1,000, more than double the national average of 5.1.

What is striking, and what makes this hard to dismiss as a poverty story, is that the gaps persist after controlling for income, education, and access to prenatal care. Affluent and college-educated Black women still face rates that look closer to developing-world numbers. Studies in JAMA and the American Journal of Obstetrics & Gynecology have documented that Black women receive less pain medication, are less likely to be believed about symptoms, and report being ignored by providers more often than other groups.

AJMC, a managed care journal, published an analysis that combines Commonwealth Fund data on healthcare spending with CDC mortality numbers. The result is a paradox that has repeated itself across nearly every recent study of the US system. The United States spends roughly twice per capita what Sweden or Norway spend on healthcare, runs the most advanced obstetric infrastructure in the world by any technological measure, and produces the worst maternal and infant outcomes of any high-income country.

The article walks through the usual candidate explanations, including fragmented postpartum care, the dominance of intervention-heavy hospital birth, the absence of universal midwifery, and the lack of paid maternity leave. None of those alone account for the full gap. The pattern is now consistent enough across datasets that researchers have stopped treating it as a question of resources and started treating it as a question of system design.

Vedam and colleagues at UBC ran the largest survey of US maternity-care mistreatment to date. The 2019 paper covered 2,138 women who had given birth in the previous three years. Across the full sample, 17.3 percent reported being mistreated by a provider, which works out to roughly one in six. The hospital-versus-home gap was striking.

Women who gave birth in hospitals reported a 28.1 percent mistreatment rate. Women who gave birth at home reported 5.1 percent.

The 5.5x gap is not explained by who chooses home birth, because the study controlled for demographics and risk factors. The specific behaviors reported included being shouted at (8.5 percent), being threatened with withheld treatment (4.5 percent), being ignored when asking for help, and having procedures performed without consent. The paper is one of the most-cited US sources on maternal mistreatment.

The Vedam team broke their mistreatment data down by race. The headline result: 32 percent of Indigenous women and 25 percent of Hispanic women in the sample reported mistreatment, compared with 14 percent of white women.

Black women in the sample reported being coerced into procedures without consent at roughly twice the white rate. The disparities held after controlling for income, education, and clinical risk factors.

This means the gaps are not explained by which kinds of women are more likely to have complicated pregnancies. They reflect differential treatment by the system. The pattern aligns with what shows up in maternal mortality data, where affluent and college-educated Black women still face worse outcomes than poor white women.

The Logan team analyzed mistreatment specifically in terms of coerced procedures, meaning procedures performed despite the mother saying no, or performed without her being given a real choice. Black women in the sample were twice as likely to report coerced procedures as white women.

The procedures most commonly described included episiotomies, internal exams, AROM (artificial rupture of membranes), and certain pharmacological inductions. The paper appeared in Birth, one of the standard journals for maternity-care research. The methodology was self-report survey, which has known limits but also captures the patient experience directly, which clinical chart review typically does not.

Hakimi and colleagues published a meta-analysis pooling data from studies of obstetric violence across multiple countries. The headline finding is that 55 percent of women worldwide report some form of obstetric violence during birth. The category includes verbal abuse, physical abuse, discrimination, and non-consented care.

Non-consented care alone showed up in 33 percent of the pooled sample. This is the first global-scale estimate that has pulled the regional studies together, and it is consistent with the smaller national surveys including the US Giving Voice work. The meta-analysis included countries with high and low income, public and private health systems, and varying maternity care models, which means the pattern is not specific to one kind of health system.

Episiotomy is a surgical cut to the perineum during the second stage of labor. It is one of the more common procedures performed without explicit consent. The Jacques team studied this directly in France and found that 60.2 percent of women who received an episiotomy reported that the clinician did not ask for consent before making the cut.

US data from ICEA, the International Childbirth Education Association, puts the equivalent number at 75 percent. Episiotomy has been associated with longer healing time, higher rates of severe tearing, increased postpartum pain, and sexual dysfunction lasting months to years. ACOG and WHO both recommend against routine use, advising the procedure only for specific indications.

Listening to Mothers III, the same 2013 survey of 2,400 US mothers cited in the interventions section, also collected detailed data on informed consent. Fewer than one in five women reported receiving complete informed consent for every procedure performed during labor. Across specific interventions, 15 percent of women reported being pressured into induction, epidural, or cesarean.

The pattern was not concentrated in particular hospitals or regions. It was distributed across the sample, which suggests the consent problem is structural rather than localized to a few bad facilities. The data has not been refreshed by a comparable national survey since, so the 2013 numbers remain the working baseline.

In 2014, the World Health Organization issued a formal statement declaring respectful care during childbirth a fundamental human right. The statement followed a decade of research documenting that mistreatment during birth was widespread enough across health systems to be considered a public health issue. The WHO defines respectful care to include freedom from physical abuse, freedom from non-consented care, freedom from discrimination, and the right to be treated with dignity.

More than seven Latin American countries have since enacted specific legislation criminalizing obstetric violence. The United States has none. There is no federal protection, no enforceable standard, and no formal definition of what constitutes mistreatment in a US labor and delivery setting.

Williams and colleagues published a review in BJOG covering the global landscape of obstetric violence legislation. Venezuela became the first country in 2007 to legally define and criminalize obstetric violence. Argentina followed in 2009.

Mexico, Bolivia, Panama, Brazil, Uruguay, and Costa Rica have similar laws on the books.

The laws vary in enforcement and reach, but they share a common structure: they define obstetric violence as a specific form of gender-based violence, list categories of behavior that qualify (forced interventions, denial of pain relief, verbal abuse), and provide a legal pathway for women to file complaints. No US state has comparable legislation. Federal law remains silent on the issue.

The Petrie-Flom Center is Harvard's bioethics and health law institute. Their 2025 analysis of forced obstetric interventions in the US starts from a sharp observation: pregnant patients are the only mentally competent adults whose right to refuse treatment is routinely overridden by physicians and the courts. Documented cases include court-ordered cesareans, court-ordered hospitalization of pregnant women who decline care, and court-ordered medical procedures on women in labor.

Florida had a high-profile case where a hospital obtained a court order for a cesarean on a competent adult who had refused it. The Supreme Court declined to take up the constitutional question in 1994, leaving the lower-court divide intact. The piece argues that this is a category of patient whose autonomy is being treated differently than any other adult in the health system.

The Kristeller Maneuver is fundal pressure: a clinician pushing down on the upper part of the uterus during the second stage of labour to speed delivery. The procedure has been associated with uterine rupture, third- and fourth-degree perineal tears, shoulder dystocia, and major pelvic floor injury. The UK banned the practice. WHO does not recommend it.

Youssef and colleagues published a 2019 case-control study in Ultrasound in Obstetrics & Gynecology that used four-dimensional transperineal ultrasound to compare women who had received the Kristeller maneuver against matched controls. Women in the Kristeller group had a 28.4 percent incidence of levator ani muscle avulsion (a tear of one of the main pelvic floor muscles, often missed clinically), compared with 14.1 percent in the control group.

After multivariate analysis, Kristeller emerged as an independent risk factor with an odds ratio of 2.5. The procedure is often performed without explicit consent. Many women describe being startled when it happens because they were not told it was coming.

INTERSECT was a 2025 cross-national study published in Psychological Medicine, one of the leading psychiatric journals. The team led by Ayers and Handelzalts pooled data from 11,302 women across 31 countries to test how consistent birth-related PTSD prevalence is across cultures, health systems, and birthing settings. The result held remarkably steady.

About 4 to 6 percent of women in every country sampled met full clinical PTSD criteria following childbirth.

Another 17 percent showed sub-clinical symptoms severe enough to impair daily functioning but not quite meeting the diagnostic threshold. The fact that the rate is consistent across 31 countries rules out the easy explanation that birth trauma is a culture-bound phenomenon or an artifact of particular hospital systems. It suggests instead that something about modern obstetric care itself is producing this rate.

The UK All-Party Parliamentary Group on Birth Trauma published a government inquiry in 2024 titled Listen to Mums. The inquiry took testimony from over 1,300 women describing traumatic births in the National Health Service. The report estimates that between 25,000 and 30,000 women in the UK develop diagnosable birth-related PTSD each year.

One of the most damning specific findings: 84 percent of women who experienced significant perineal tears reported that they had not been properly informed beforehand about the risk or the consequences. The report led to formal recommendations for systemic NHS reform, including mandatory informed consent before any episiotomy or assisted delivery and a national standard for postnatal mental health screening. Most of those reforms have not yet been enacted.

Yildiz, Ayers and Phillips published a 2017 meta-analysis in the Journal of Affective Disorders that pulled together 59 separate studies of birth-related PTSD, covering 24,267 women in total. The team distinguished community samples (women from the general population) from high-risk samples (women with prior trauma, complications, or specific risk factors).

In community samples, clinical PTSD prevalence was 3.3 percent during pregnancy and 4.0 percent in the postpartum period. In high-risk samples, the numbers rose sharply to 18.95 percent prenatally and 18.5 percent postpartum.

The pattern matches what the more recent INTERSECT study found across 31 countries. The clinical PTSD rate is one number. The broader "I experienced my birth as traumatic" subjective rate is consistently higher across surveys, often in the 20 to 45 percent range, which captures women who do not meet full diagnostic criteria but still carry the experience forward.

Greenfield and colleagues published a 2019 study in Frontiers in Psychology examining how birth trauma affects subsequent reproductive decisions. The headline finding: 53 percent of women who reported their first birth as traumatic were less likely to have additional children than they had originally planned.

The team surveyed women several years after the birth, which gave time for the immediate emotional response to settle into a stable pattern. Common reasons given included fear of repeating the trauma, persistent physical symptoms from the first birth, and changes in the woman's sense of what kind of mother she could be. The effect held across different definitions of traumatic and across maternal age groups, which suggests it is not a temporary response to a hard delivery.

Daniels and colleagues published one of the few studies examining birth-related PTSD in partners, specifically in fathers, in 2020 in BMC Pregnancy and Childbirth. About 1 percent of fathers who attended their partner's birth met clinical PTSD criteria afterward. In the UK, where roughly 90 percent of fathers attend the birth, that 1 percent works out to between 6,000 and 7,000 men per year.

The most common features described in the qualitative data were feeling helpless watching what was happening, self-blame for not protecting their partner, and breakdown of the relationship in the year following. The study is small and the field is underdeveloped, but the data argue that the trauma extends beyond the woman giving birth. Partners are also affected, and they are even less likely to be screened or treated.

The Bohren Cochrane review is the strongest evidence in the doula literature, and Cochrane is the strongest type of evidence in medicine generally. The team pooled data from 26 randomized controlled trials covering 15,800 women across multiple countries.

The results showed continuous one-on-one labor support reduced cesareans by 25 percent, reduced instrumental deliveries by 10 percent, reduced low Apgar scores by 38 percent, increased spontaneous vaginal births by 8 percent, and shortened labor by 41 minutes on average. Women reported 35 percent fewer negative birth experiences when they had continuous support. The review documented zero harms across all 26 trials.

The effect was strongest when the support came from someone independent of the hospital staff and the woman's social network. That last point matters. A doula is not the same as the partner being present, and the evidence is clearer for the doula role than for additional social support generally.

The Falconi team published a 2022 study in Lancet eClinicalMedicine examining doulas and postpartum mental health. Women who had doula support during pregnancy and labor showed 57.5 percent lower odds of postpartum depression or anxiety. For the women who specifically had a doula present during labor itself, the reduction in PPD/PPA odds was 64.7 percent.

The cesarean rate among women with doula care was 18.7 percent, compared with 30.7 percent without. The study used propensity-score matching to control for the kinds of women who tend to choose doula care, which addresses the obvious selection-bias concern. The results held after adjustment.

Karwa and colleagues published the first large-scale study of virtual doula care in Obstetrics & Gynecology in 2024, analyzing roughly 9,000 users of the Maven Clinic digital platform. Users who completed two or more virtual doula appointments had a 20 percent reduction in odds of cesarean (aOR 0.80) compared with matched controls.

The effect was substantially stronger in Black users with two or more visits, who showed a 68 percent reduction in cesarean odds (aOR 0.32). The study also found a dose-response relationship: more sessions correlated with larger effect sizes, which is the kind of pattern that strengthens causal inference. The results suggest virtual doula care can deliver comparable benefits to in-person care, which has practical implications for access, especially in rural areas where in-person doulas are not available.

ACOG, the American College of Obstetricians and Gynecologists, issued Committee Opinion 766 in 2019 endorsing doula care. The specific language: doula support is "one of the most effective tools to improve labor and delivery outcomes." This endorsement matters because ACOG is the professional body that sets the practice standard for the majority of US obstetricians.

The opinion includes the evidence base from the Cochrane review and recommends that women have access to continuous labor support. Implementation has been slow. Most US hospitals do not yet make doulas part of standard care, and most US insurance plans do not cover doula services, though Medicaid coverage is expanding rapidly.

Evidence Based Birth pulled together the doula literature into a single overview, including the satisfaction data that the clinical studies do not always foreground. Across the studies they reviewed, women with doula support reported 92 percent satisfaction with their birth experience.

The effect was strongest when the doula was trained and independent of both hospital staff and the woman's family. One question the literature addresses directly is whether a doula displaces the partner's role. The answer is the opposite.

Partners of women who had doulas reported feeling more confident, more useful, and more present during the birth. The doula handles the continuous emotional and physical support, which frees the partner to be the partner rather than trying to fill both roles.

The Lemon team published a study in the American Journal of Obstetrics & Gynecology (epub August 2024, print April 2025) that quantified the benefits of doula care across the full maternity continuum using propensity-score matching. The matching approach addresses the obvious concern that women who choose doula care may differ in other ways from women who do not.

After adjustment, doula care was associated with significantly more VBACs (15.6 to 34.2 additional VBACs per 100 patients), more postpartum office visit attendance, higher exclusive breastfeeding (7.9 to 11.4 more per 100), and fewer preterm deliveries (3.8 to 4.0 fewer per 100). The paper strengthens the case that the doula effect extends well beyond the labor itself, into postpartum recovery, breastfeeding establishment, and the prevention of preterm birth, which is one of the harder outcomes to move in maternal health.

Kozhimannil's 2013 paper in the American Journal of Public Health is the foundational US study on doulas in publicly funded care. The team analyzed Medicaid births and compared outcomes for women who received doula support with those who did not.

Cesarean rates were 22.3 percent for the doula group versus 31.5 percent for the no-doula group. Breastfeeding initiation was 97.9 percent with doula versus 80.8 percent without.

The effect on Black women's breastfeeding was particularly large, 92.7 percent versus 70.3 percent, which closed nearly the entire racial gap on that outcome. The team calculated that for every nine women receiving doula support, one cesarean was prevented. The paper became the evidence base for subsequent Medicaid policy expansion.

The follow-up 2016 Kozhimannil paper in Birth ran the economic analysis. If doula care were available to all US Medicaid beneficiaries, the projected annual savings would be 58.4 million dollars, primarily through reduced cesarean rates and reduced NICU admissions. The paper was instrumental in driving state-level Medicaid policy.

In 2020, two US states covered doula care under Medicaid. By 2026, 26 states plus DC do.

Washington pays up to 3,500 dollars per Medicaid client for doula services. The expansion has been one of the fastest policy shifts in US maternal health, driven directly by this cost-effectiveness evidence combined with the clinical outcome data.

The CDC tracks vaginal birth after cesarean (VBAC) rates through Data Brief No. 359, published in March 2020 covering 2016 to 2018. The national VBAC rate rose from 12.4 percent in 2016 to 12.8 percent in 2017 and 13.3 percent in 2018.

The rate increased in 17 states and declined in only 1. All race and Hispanic-origin groups had higher VBAC rates in 2018 than in 2016, with the single exception of non-Hispanic Native Hawaiian or Other Pacific Islander women.

VBAC success rates when attempted run around 70 percent overall in the broader literature, with home birth registries (MANA) reporting around 87 percent. The numbers matter because the conventional approach in the US for the last several decades has been "once a cesarean, always a cesarean," which is not what the evidence supports. ACOG updated its guidelines years ago to support VBAC for appropriate candidates, but many hospitals still refuse to offer it, often citing malpractice insurance constraints rather than clinical evidence.

James McKenna founded and ran the Mother-Baby Behavioral Sleep Laboratory at the University of Notre Dame, where he and colleagues spent over three decades documenting the physiology of mother-infant cosleeping. The research used laboratory polysomnography to measure what actually happens during the night when mothers and infants share a bed. The findings have been consistent across studies. Cosleeping mother-infant pairs synchronize sleep stages.

Babies move through more transitions between sleep states, which appears to be protective against the kind of deep sleep that is associated with SIDS in infants who do not yet have full breathing control. Breastfeeding mothers and their infants show even tighter synchrony, and bed-sharing breastfeeding dyads breastfeed twice as often per night as non-bed-sharing pairs, with most of the feeds going unremembered by the mother in the morning. McKenna is the most cited researcher in the cosleeping literature.

Helen Ball runs the Parent-Infant Sleep Lab at Durham University in the UK. Her research focuses specifically on how cosleeping interacts with breastfeeding outcomes.

The headline findings: bed-sharing mothers breastfeed for significantly longer and breastfeed more exclusively than mothers who room-share or sleep separately. In one Durham study, mothers who bed-shared in the first six months were three times more likely to still be breastfeeding at 16 weeks compared with mothers who did not. The mechanism is straightforward.

Babies who feed at night without requiring the mother to fully wake and walk to another room tend to feed more often, which maintains the milk supply and the breastfeeding relationship. The Ball lab data has been instrumental in shifting UK public health guidance toward acknowledging safe bed-sharing as a real category.

The Safe Sleep 7 is a set of conditions developed by researchers including McKenna, La Leche League International, and analyzed against datasets including the work of Peter Blair. The conditions describe when bed-sharing has been associated with the same or lower risk profile as separate sleeping.

The seven conditions: the mother does not smoke, is sober (no alcohol or sedating drugs), is breastfeeding, has a healthy full-term baby, places the baby on its back, the baby is lightly dressed and unswaddled, and the bed is firm with no pillows, gaps, or soft bedding near the baby's face. When all seven conditions are met, the SIDS risk associated with bed-sharing drops substantially in the available data. The Bombard et al.

CDC paper in 2018 documented the trends in safe sleep practices. The framework gives a structured way for parents to assess whether their specific bed-sharing context is the kind that the research supports.

Peter Blair and colleagues used data from the Avon longitudinal study, one of the largest UK birth cohorts, to examine SIDS risk in bed-sharing infants under different conditions. The headline finding: in non-smoking parents who had not consumed alcohol or sedating drugs, bed-sharing with a healthy full-term breastfed infant on a regular bed showed no increased SIDS risk compared with separate sleeping.

The risk emerged specifically when smoking, alcohol, soft bedding, or sofa-sleeping entered the picture. The paper appeared in BMJ Open in 2014. The work has been important in shifting the public health conversation from "bed-sharing is dangerous" to "bed-sharing under specific conditions is the problem." Blair's group has continued to publish updates that consistently support the conditional safety framing.

Melissa Bartick is a US researcher who has published extensively on infant feeding and sleep safety. Her work, including a 2019 paper with Cecília Tomori, drew a sharp distinction that the AAP has often blurred. Sofa-sleeping with an infant is among the highest-risk infant sleep arrangements identified in the data, while bed-sharing under safe conditions is much lower risk.

Bartick's argument has been that conflating the two in public health messaging actively drives unsafe outcomes, because mothers who fall asleep nursing on a couch (often because they have been told never to bring the baby into the bed) end up in the most dangerous configuration. The paper called for the AAP to revise its messaging to distinguish bed-sharing from sofa-sleeping. As of 2026, the AAP has not done so.

The UNICEF UK Baby Friendly Initiative is the British arm of the global UNICEF/WHO Baby Friendly program, which sets standards for maternity and infant feeding services. Its position on bed-sharing differs sharply from the AAP.

UNICEF UK explicitly recognizes that bed-sharing happens in most breastfeeding families regardless of public health messaging, and provides safe bed-sharing guidance rather than blanket discouragement. The guidance is based on the conditional-safety evidence from Blair and others.

The UK NHS adopted aligned messaging in 2014, and Lullaby Trust, the UK's main SIDS charity, has supported safe bed-sharing guidance since then. The contrast with US public health messaging is direct. Both countries read the same research base.

The 2015 McKenna and Gettler paper in Acta Paediatrica argued for a conceptual reframing. The title states their position: "There is no such thing as infant sleep, there is no such thing as breastfeeding, there is only breastsleeping." The argument is that mother-infant cosleeping with breastfeeding is so physiologically integrated that treating them as separate behaviors misrepresents the biology.

Babies who sleep near their mother feed more often, regulate their breathing and temperature in response to the mother's, and show measurable differences in physiological state compared with infants who sleep separately. The paper has been cited widely in the evolutionary anthropology and lactation literature, and is one of the most influential recent papers on the conceptual basis of cosleeping research.

The Mileva-Seitz, Bakermans-Kranenburg, Battaini and Luijk review in Sleep Medicine Reviews systematically examined 659 published papers on parent-child bed-sharing. The review pulled together evidence on socioeconomic and cultural correlates of the practice, purported risks (including SIDS and sleep problems), and developmental outcomes including attachment, cognitive development, behavioral outcomes, and parent-child relationship measures.

The pooled finding on outcomes was that bed-sharing had either no association or a positive association with the developmental measures studied, and no consistent evidence of negative effects on attachment, independence, or social development. The review covered cosleeping practices across cultures. The conclusion noted that the cultural narrative warning that cosleeping creates dependent or maladjusted children is not supported by the developmental research base.

Melvin Konner (Emory) and Meredith Small (Cornell) are two anthropologists whose work documented infant sleep practices across cultures. Konner's work with the Ju/'hoansi people of the Kalahari documented continuous mother-infant contact day and night, with no separate infant sleep arrangements.

Small's book 'Our Babies, Ourselves' synthesized cross-cultural data from dozens of societies, including the rapidly shrinking number that still practiced traditional infant care. The pattern was consistent.

Separating mothers and infants for sleep is a recent practice, largely confined to industrialized Western societies, and it represents a sharp departure from what infants have evolved to expect. This does not by itself prove cosleeping is better. It does establish that the species norm is cosleeping, and that the burden of proof should sit on the practice that is the historical anomaly.

The American Academy of Pediatrics issued updated Safe Sleep Recommendations in 2022, maintaining its long-standing position that bed-sharing should be avoided for all infants under one year of age. The AAP cites pooled SIDS data showing elevated risk for bed-sharing infants, particularly in the first three months.

The recommendation does not differentiate between safe and unsafe bed-sharing contexts. The AAP position is the strongest opposing evidence to the cosleeping case, and it carries weight because the AAP is the dominant US pediatric authority.

The criticisms of the AAP position, including those from Bartick and McKenna, are that the data pools together fundamentally different situations (sofa-sleeping, smoking, alcohol, soft bedding, breastfed vs formula-fed) and assigns the risk to bed-sharing as a category rather than to the specific risk factors. The AAP has been asked to revise its messaging multiple times. It has not done so.

Wennergren and colleagues published a 2021 paper in Acta Paediatrica analysing Swedish national surveys of infant sleep practices over 15 years. Bed-sharing among 6-month-old infants nearly doubled, rising from 20 percent in the 2003-2004 survey to 33 percent in 2018.

The surveys also found a strong positive correlation between bed-sharing and breastfeeding rates. Sweden has one of the lowest infant mortality rates in the world (2.1 per 1,000 live births, compared with the US 5.1), and bed-sharing has been rising over the same period that infant mortality has been falling. The Swedish National Board of Health and Welfare (Socialstyrelsen) introduced a bed-sharing warning in 2013 aimed at preventing SIDS, but the gap between official guidance and family practice is wide and known to the agency, which has been reviewing its recommendations after criticism from parents and specialists.

Duong and colleagues compared 47 Vietnamese children, raised in a tradition that begins potty training in the first months, with 57 Swedish children trained the conventional late way. By six months, 89 percent of the Vietnamese babies were on daily potty training. By two years, 98 percent were finished. In the Swedish group, only 5 percent had even started by 24 months.

The striking physiological finding is that the early-trained babies showed complete bladder emptying, no residual urine, by around nine months, while the Swedish children first reached that point at around 36 months, with fewer voids and lower volumes (p < 0.001). Early, responsive elimination did not appear to harm bladder development. If anything it tracked with earlier, healthy bladder maturation.

The catch is that this compares two whole cultures, not a randomized trial, so other differences between them could play a part. It is the cleanest published signal that starting early is genuinely feasible and physiologically fine, not proof that it causes the difference.

This is the largest data point behind the idea that earlier is better. In 11,090 Chinese families, starting elimination communication before the first birthday was associated with about 80 percent lower odds of disposable diaper dependence by preschool age (adjusted odds ratio 0.204). The diaper-dependent children also reported more diaper rash, more urinary urgency, and more recurrent infections.

The effect is large and the sample is huge, which makes the association precise. What it cannot do is prove direction. This is a cross-sectional survey, so recall bias and reverse causation are real: a child with bladder problems may stay in diapers longer rather than the diapers causing the problem.

We present it for what it is, the strongest start-before-they-are-walking signal available, with the asterisk that it is correlation, not a controlled trial.

This is the highest-tier source on the downside of waiting. Li, Wen and colleagues pooled ten studies covering more than 24,000 children aged five to seventeen. Children trained at a younger age had significantly less lower-urinary-tract dysfunction, with a pooled odds ratio of 0.71. Training at or after 24 months was where the risk climbed.

The subgroups pointed the same way, less daytime incontinence and less bedwetting among earlier-trained children. The effects are modest, roughly a 25 to 30 percent relative difference, but consistent and robust to sensitivity analysis.

The caveat is that every study pooled here is observational, so this is a strong, repeated association rather than proof that delaying training causes the problems. Read it alongside the U-curve study below, which shows that forcing training too early is also a mistake.

Carr and colleagues compared caregiving and skin outcomes across 1,791 babies in China, the United States, and Germany. The Chinese infants spent the least time in an overnight diaper and had the lowest rate of diaper dermatitis, along with lower skin pH and less water loss through the skin, both signs of a healthier skin barrier.

Diaper rash is one of the most common everyday problems of infancy, affecting a large share of babies, so a real reduction matters. The authors concluded that caregiver behaviors, including thorough cleaning after stooling and reduced time in an overnight diaper, were associated with less dermatitis and a better skin barrier.

The limit is that this is observational, and reduced diaper time was bundled with other good habits, so it does not isolate diaper-free time as the single cause. It is solid support for the simple idea that skin does better with a break from the diaper.

This 1977 study in Pediatrics is the foundational anthropological source for the idea that diaper-free infant care is not a fringe trend but a human norm. Among the Digo of coastal Kenya, caregivers believe infants can learn soon after birth and begin elimination training in the first weeks of life. With what the authors call a nurturant conditioning approach, warm and responsive rather than coercive, day and night dryness is reported by five to six months.

The authors concluded that sociocultural factors matter more in toilet-training readiness than is usually assumed. In other words, the Western belief that a child cannot manage elimination until age three is a cultural assumption, not a developmental law.

It is a single observational study of one culture from 1977, so it shows what is possible and normal elsewhere, not that early training is universally optimal or causes any benefit. As the cross-cultural anchor, it does exactly one job well: it proves early, gentle continence is genuinely achievable.

Diapers are a steady line item for years. In the US they run about 840 to 1,200 dollars per child per year (The Bump's 2025 survey, reported by Consumer Reports). In Sweden the Konsumentverket calculation puts diapers at about 4,756 SEK per year per child. Over two to three years of diapering that compounds into a few thousand dollars, or tens of thousands of kronor.

It is not a small expense for many families either. Nearly half of US families with young children report struggling to afford enough diapers.

The benefit here is simple arithmetic. Coming out of diapers earlier means buying fewer of them, which is money that stays in the family's pocket.