To understand the relationship between birth order and “late” delivery, we studied more than 2 million pregnancies resulting in a live, full-term, single birth between 37- and 43-weeks’ gestation, excluding inductions or cesarean deliveries. We compared gestational duration and rate of delivery beyond 41 weeks between those who have had a prior delivery and those who have not.

When evaluating the rate of deliveries taking place past 41 weeks’ gestation, we found that 6.2% of first-time deliveries among mothers with no prior pregnancy extended beyond this point. This was 1.53 times more often than for those with a prior delivery, where only 4.0% delivered after 41 weeks. Among mothers with a prior pregnancy loss before 20 weeks, 5.8% of first full-term births occurred after 41 weeks.

When looking at the distribution of gestational age at delivery, we found that patients who have not had a prior delivery have an average gestation of 275.9 days compared to 274.5 days among mothers who have delivered before, a statistically significant difference, as seen in Figure 1.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

1. Caughey AB, Stotland NE, Washington AE, Escobar GJ. Who is at risk for prolonged and postterm pregnancy?. Am J Obstet Gynecol. 2009;200(6):683.e1-683.e6835. doi:10.1016/j.ajog.2009.02.034
2. Astolfi P, Zonta LA. Risks of preterm delivery and association with maternal age, birth order, and fetal gender. Hum Reprod. 1999;14(11):2891-2894. doi:10.1093/humrep/14.11.2891

We studied more than 1.6 billion face-to-face outpatient visits in 2024, comparing no-show rates for patients with and without an established patient portal account at the time the appointment was scheduled.  

Overall, patients with an active patient portal had a no-show rate of 6.2%, compared to 7.9% for those without, as seen in Figure 1. Patients aged 50–64 saw the greatest percentage point difference (6.2% vs. 8.7%) followed by those aged 35–49 (7.8% vs. 9.9%). Younger patients had smaller gaps, with the smallest difference seen among 18–34-year-olds (9.3% vs. 10.9%). 

Converting this finding to a rate, approximately 1,700 fewer no-shows occurred for patients with portal accounts per every 100,000 scheduled visits. This equates to more than 21 million fewer no-shows in one year across the 1.26 billion scheduled visits among patient-portal users in 2024. 

A sensitivity analysis accounting for other factors such as patient demographics, social vulnerability, appointment lead time, rate of no-shows in 2023, social drivers of health, insurance type, and number of recent visits showed similar patterns. 

These data come from summarized metrics of organizations that use the Epic EHR to provide direct patient care. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.   

1. Carini E, Villani L, Pezzullo AM, et al. The Impact of Digital Patient Portals on Health Outcomes, System Efficiency, and Patient Attitudes: Updated Systematic Literature Review. J Med Internet Res. 2021;23(9):e26189. Published 2021 Sep 8. doi:10.2196/26189

To explore the relationship between osteoporosis medications and cardiovascular events, we studied 447,208 patients with osteoporosis or osteopenia. We factored in patient age, sex, BMI, smoking status, and histories of hyperlipidemia, diabetes, chronic kidney disease, and cardiovascular disease. Patients prescribed more than one of the studied medications within the follow-up period were excluded. 

We found that patients prescribed bisphosphonates were slightly less likely to experience an ischemic stroke compared to patients prescribed calcium or vitamin D. Patients prescribed denosumab were 23% more likely to be diagnosed with AFib, while patients prescribed teriparatide were 44% more likely to be diagnosed with AFib and 35% more likely to experience an MI than patients prescribed calcium or vitamin D. Patients prescribed romosozumab or abaloparatide were not conclusively more or less likely to experience the conditions studied compared to those prescribed calcium or vitamin D. 

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 298 million patient records from 1,700 hospitals and more than 39,000 clinics from all 50 states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Azeez TA. Osteoporosis and cardiovascular disease: a review. Mol Biol Rep. 2023;50(2):1753-1763. doi:10.1007/s11033-022-08088-4 
2. Lv F, Cai X, Yang W, et al. Denosumab or romosozumab therapy and risk of cardiovascular events in patients with primary osteoporosis: Systematic review and meta- analysis. Bone. 2020;130(115121):115121. doi:10.1016/j.bone.2019.115121 
3. Osteoporosis treatment: Medications can help. Mayo Clinic. Published August 28, 2024. https://www.mayoclinic.org/diseases-conditions/osteoporosis/in-depth/osteoporosis-treatment/art-20046869. Accessed September 13, 2024. 

We studied 597,531 children from birth through age 6 and categorized them based on the number of antibiotic courses the child received in the first year of life. We limited our analysis to antibiotics in the first year of life to avoid potential conflation with antibiotics often prescribed in later childhood as part of an assessment for celiac disease. We included patient demographics, gestational age and delivery method, frequency of outpatient care, number of first year infections, and maternal history of celiac disease in our analysis. 

Overall, while antibiotic use was associated with a lower likelihood of being diagnosed with celiac disease by age 6, this result was only significant for those who had 3-5 prescriptions, as seen in Figure 1.  

We found similar results when assessing antibiotic use before age 3, celiac disease by age 3, and in patients without a history of surgery.  

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Definition & facts for celiac disease. National Institute of Diabetes and Digestive and Kidney Diseases. April 15, 2025. https://www.niddk.nih.gov/health-information/digestive-diseases/celiac-disease/definition-facts. Accessed April 22, 2025. 
2. Kołodziej M, Patro-Gołąb B, Gieruszczak-Białek D, et al. Association between early life (prenatal and postnatal) antibiotic administration and coeliac disease: a systematic review. Arch Dis Child. 2019;104(11):1083-1089. doi:10.1136/archdischild-2019-317174 
3. Kamphorst K, Van Daele E, Vlieger AM, Daams JG, Knol J, van Elburg RM. Early life antibiotics and childhood gastrointestinal disorders: a systematic review. BMJ Paediatr Open. 2021;5(1):e001028. Published 2021 Mar 3. doi:10.1136/bmjpo-2021-001028 

We studied 509,895 patients who had a sterilization procedure performed between 2015 and 2024 to better understand the evolving dynamics of tubal ligations and salpingectomies. We found that the salpingectomy-to-tubal ligation ratio rose from 1.2 in 2015 to 3.3 in 2024. Notably, the accelerated trend after 2019 coincides with the publication from The American College of Obstetricians and Gynecologists that demonstrated the protective benefits of salpingectomy against ovarian cancer. 

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 294 million patient records from 1,600 hospitals and more than 37,000 clinics from all 50 states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Opportunistic salpingectomy as a strategy for epithelial ovarian cancer prevention. The American College of Obstetricians and Gynecologists. 4/2019. https://www.acog.org/clinical/clinical-guidance/committee-opinion/articles/2019/04/opportunistic-salpingectomy-as-a-strategy-for-epithelial-ovarian-cancer-prevention. Accessed January 27, 2025. 

In the first quarter of 2015, lingual frenotomy occurred in 98 per 10,000 babies. The rate rose to a peak of 212 per 10,000 babies in the second quarter of 2021, as seen in Figure 1. The rate then trended down slightly, to 158 per 10,000 babies in the last quarter of 2024. 

Next, we looked at the association between lingual frenotomies and the outcomes of sleep disorders and speech disorders among children who were diagnosed with tongue-tie. We compared patients who did not have surgery to those that did have surgery and included patient sex, social vulnerability, rural-urban classification, and prematurity status in our analysis.  

We found that rates of obstructive sleep apnea and speech disorders were not significantly different between the populations, as seen in Figure 2. Children who had a prior frenotomy had slightly higher rates of central sleep apnea (422 per 10,000 babies vs. 307 per 10,000 babies) by their fifth birthday. Limiting the analysis to patients with a diagnosed feeding difficulty showed similar results. 

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Carnino JM, Rodriguez Lara F, Chan WP, Kennedy DG, Levi JR. Speech Outcomes of Frenectomy for Tongue-Tie Release: A Systematic Review and Meta-Analysis. Ann Otol Rhinol Laryngol. 2024;133(6):566-574. doi:10.1177/00034894241236234 
2. Messner AH, Walsh J, Rosenfeld RM, et al. Clinical Consensus Statement: Ankyloglossia in Children. Otolaryngol Head Neck Surg. 2020;162(5):597-611. doi:10.1177/0194599820915457 

We aimed to understand trends in HbA1c testing and prediabetes among teenage patients. We studied 18,182,111 teens aged 13–18 who had at least one healthcare visit between Q1 2018 and Q1 2025, with 1,000,628 receiving an HbA1c test. 

We found that HbA1c testing rates have increased since 2018. In the first quarter of 2018, 1.4% of male teens had their HbA1c tested, compared to 2.2% in the first quarter of 2025, as seen in Figure 1. Similarly, the HbA1c testing rate for female teens rose from 1.4% to 2.5% over the same period. Rising testing rates may indicate that there are more teens considered at increased risk of developing diabetes. It may also indicate better screening of teens who are at increased risk. 

Over the study period, the proportion of HbA1c tests for male teens that met prediabetic HbA1c thresholds (5.7–6.4%) rose from 14% in the first quarter of 2018 to 16% in the first quarter of 2025. HbA1c tests for female teens, on the other hand, had steady positivity rates of around 12% in the same period. 

Because testing rates have increased, the absolute incidence of newly identified prediabetic-level HbA1c results has also risen, as shown in Figure 3. Among male teens, 19 per 10,000 had a prediabetic HbA1c in the first quarter of 2018, compared to 35 per 10,000 in the first quarter of 2025—an 84% increase. For female teens, the incidence rose from 16 to 28 per 10,000 over the same period, marking a 75% increase.  

Previous research shows that obesity is a strong modifiable risk factor for insulin resistance in youth, so we stratified teens with a prediabetic HbA1c by their BMI classifcation.⁴ We found that more than half had a BMI classifying them as obese, while an additional roughly 10% were classified as overweight. These proportions were consistent across patient sex and time.  

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 300 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Prediabetes – your chance to prevent type 2. U.S. Centers for Disease Control and Prevention. May 15, 2024. https://www.cdc.gov/diabetes/prevention-type-2/prediabetes-prevent-type-2.html?CDC_AAref_Val=https://www.cdc.gov/diabetes/basics/prediabetes.html. Accessed May 12, 2025. 
2. Prediabetes and type 2 diabetes: Screening. (2021, August 24). U.S. Preventive Services Task Force. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/screening-for-prediabetes-and-type-2-diabetes. Accessed May 12, 2025. 
3. American Diabetes Association. (2018). 2. Classification and diagnosis of diabetes: Standards of Medical Care in diabetes-2018. Diabetes Care, 41(Suppl 1), S13–S27. https://doi.org/10.2337/dc18-S002 
4. Ouyang, A., Hu, K., & Chen, L. (2024). Trends and risk factors of diabetes and prediabetes in US adolescents, 1999-2020. Diabetes Research and Clinical Practice, 207(111022), 111022. https://doi.org/10.1016/j.diabres.2023.111022 

To understand the differences in overall effectiveness of antihypertensive treatment by sex, we studied non-pregnant adult patients who started treatment for hypertension and had a baseline systolic blood pressure (SBP) greater than 130 mmHg, which is considered hypertensive.⁴ We factored patient demographics, baseline blood pressure, comorbidities, prior medication use, and smoking status into our analysis. 

One month into treatment, women were 10.7% more likely to achieve blood pressure control (SBP under 130 mmHg) compared to men, as seen in Figure 1. This difference persisted at three months, albeit slightly reduced, with women 9.5% more likely to achieve an SBP under 130mmHg than men.  

Next, we evaluated long-term outcomes, including stroke and atherosclerotic cardiovascular disease (ASCVD) events. ASCVD events include myocardial infarction (MI), peripheral arterial disease, and acute coronary syndrome. We found that women were 4.3% less likely to have a stroke and 23.8% less likely to have an ASCVD event within three years of starting the treatment, as seen in Figure 2. 

Individual medication dosages and patient adherence to their prescribed medication were not studied as part of this analysis. Additionally, even though baseline SBP differs by sex, we found similar results after adjusting for baseline SBP. 

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 299 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Whelton PK, Carey RM, Aronow WS, et al. 2017 ACC/AHA/AAPA/ABC/ACPM/AGS/APhA/ASH/ASPC/NMA/PCNA Guideline for the Prevention, Detection, Evaluation, and Management of High Blood Pressure in Adults: A Report of the American College of Cardiology/American Heart Association Task Force on Clinical Practice Guidelines [published correction appears in Hypertension. 2018 Jun;71(6):e140-e144. doi: 10.1161/HYP.0000000000000076.]. Hypertension. 2018;71(6):e13-e115. doi:10.1161/HYP.0000000000000065 
2. Reckelhoff JF. Gender differences in the regulation of blood pressure. Hypertension. 2001;37(5):1199-1208. doi:10.1161/01.hyp.37.5.1199 
3. Sandberg K, Ji H. Sex differences in primary hypertension. Biol Sex Differ. 2012;3(1):7. Published 2012 Mar 14. doi:10.1186/2042-6410-3-7 
4. LeWine, H. E. (2024, March 26). Reading the new blood pressure guidelines. Harvard Health. https://www.health.harvard.edu/heart-health/reading-the-new-blood-pressure-guidelines. Accessed May 14, 2025. 

We studied 11,764,325 women aged 40 to 74 with no prior history of breast cancer who had a medical visit in 2024 and another at least two years prior. To assess breast cancer screening history, we reviewed care provided within the three years prior to their visit in 2024.

We found that patient portal users consistently had higher rates of screening in alignment with USPSTF screening recommendations in each age group studied, as seen in Figure 1.

White patients had the largest gap between portal users and non-users, and White non-portal users were screened at the lowest rate compared to patients of other races and ethnicities at 53.9%, as seen in Figure 2. Breast cancer screening rates were the highest among Black portal users at 81.4%, while Black non-users were screened 66.2% of the time.

Women classified as high risk had higher screening rates than all other studied groups, with portal users still having higher rates than non-users (89.0% for users vs. 81.3% for non-users), as seen in Figure 3. Among women not classified as high risk, portal users still had higher screening adherence (74.8% for users vs. 57.0% for non-users). However, high-risk non-users had higher screening rates than not-high-risk portal users.

Of note, screenings that occur outside of a Cosmos-participating organization are not always documented, which might contribute to an undercounting of screenings in this analysis.

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 298 million patient records from 1,700 hospitals and more than 39,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson.

1. Breast cancer: Screening. U.S. Preventative Services Task Force. April 30, 2024. https://www.uspreventiveservicestaskforce.org/uspstf/recommendation/breast-cancer-screening. Accessed February 18, 2025.
2. Huang J, Chen Y, Landis JR, Mahoney KB. Difference Between Users and Nonusers of a Patient Portal in Health Behaviors and Outcomes: Retrospective Cohort Study. J Med Internet Res. 2019;21(10):e13146. Published 2019 Oct 7. doi:10.2196/13146

To better understand trends in SSIs, we studied 5,357,545 surgeries performed between January 1, 2019, and September 30, 2024, by procedure type, including colorectal surgery, cesarean section (C-section), hip replacement, knee replacement, and abdominal hysterectomy. These procedures represent the most common types of procedures with data reported to the National Healthcare Safety Net (NHSN).² 

Colorectal surgeries consistently demonstrated the highest rate of SSI across the study period, as seen in Figure 1. Following a temporary decline in early 2020—possibly due to pandemic-related reductions in elective surgery volumes and enhanced infection control³—colorectal surgery infection rates returned to previous rates and then rose steadily, reaching 7.4% in Q3 2024 from 6.1% in Q4 2019.  

C-sections saw a slight rise in SSI rates from 1.0% in Q2 2020 to 1.3% in Q3 2024, maintaining relatively low infection rates overall. Hysterectomy-related SSIs fluctuated more, while still having relatively low infection rates. Knee replacement infection rates remained 0.8% or less in all quarters, while hip replacement SSIs were 1.5% or less.  

Of note, infection preventionists manually link infections to procedures to identify them as SSIs, which could introduce variability in case identification. 

These data come from Cosmos, a dataset created in collaboration with a community of Epic health systems representing more than 299 million patient records from 1,700 hospitals and more than 40,000 clinics from all 50 U.S. states, Lebanon, and Saudi Arabia. This study was completed by two teams that worked independently, each composed of a clinician and research scientists. The two teams came to similar conclusions. Graphics by Brian Olson. 

1. Surgical site infection. World Health Organization. https://www.who.int/teams/integrated-health-services/infection-prevention-control/surgical-site-infection. Accessed April 15, 2025. 
2. Surgical Site Infection Event (SSI). U.S. Centers for Disease Control and Prevention. 1/2025.  https://www.cdc.gov/nhsn/pdfs/pscmanual/9pscssicurrent.pdf. Accessed April 24, 2025. 
3. Mehta A, Awuah WA, Ng JC, et al. Elective surgeries during and after the COVID-19 pandemic: Case burden and physician shortage concerns. Ann Med Surg (Lond). 2022;81:104395. doi:10.1016/j.amsu.2022.104395 
4. Surgical Site Infection (SSI) Events. (2025, January 1). U.S. Centers for Disease Control and Prevention. https://www.cdc.gov/nhsn/psc/ssi/index.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fnhsn%2Facute-care-hospital%2Fssi%2Findex.html