Dr. Chen is a fellowship-trained urologist who specializes in male reproductive medicine. He is a clinical assistant professor in the Department of Urology at Stanford University School of Medicine.
Dr. Chen diagnoses and treats male infertility, erectile dysfunction, Peyronie’s Disease, Benign Prostatic Hyperplasia (BPH), hypogonadism, and other disorders of the male genitourinary tract. He emphasizes getting to know the whole patient and utilizing a stepwise approach to treatment when appropriate. When surgery is required, he excels at scrotal surgery, minimally invasive prostate de-obstruction, penile implant placement, microsurgical vasectomy reversal, varicocele treatment, and surgical sperm retrieval.
For every patient, Dr. Chen develops a personalized care plan emphasizing innovation, safety, and compassion.
Dr. Chen has published his research findings in journals including Urology Practice, the Journal of Sexual Medicine, Endocrine, the Journal of Pediatric Urology, Journal of Endourology, and elsewhere. Topics have included the association between mortality and male infertility, the association of the COVID-19 pandemic on male sexual function, national trends in vasectomy, and more. He co-wrote the chapter “Simulation and Ureteroscopy” for the textbook Ureteroscopy.
Dr. Chen is also an innovator with an interest in bringing novel technologies to the field of benign Urology. He has a background in the use of simulation science in medical teaching as well as in prototype design. He has received grant funding to prepare robotic surgeons for acute operating room scenarios and holds a provisional patent on a system for automated urine assessment and monitoring in the hospital.
He has made presentations on male infertility and surgical simulation at meetings of the American Urological Association, American College of Surgeons, and Sexual Medicine Society.
Dr. Chen has won recognition for his research and clinical achievements. He has received awards from the Western Section of the American Urological Association, American College of Surgeons, Society of Urologic Prosthetic Surgeons, and Sexual Medicine Society of North America.
He is a member of the American Urological Association, American College of Surgeons, International Society for Sexual Medicine, American Society for Reproductive Medicine, and Western Section of the American Urological Society.
- Male Reproductive Medicine
- Male Infertility
- Erectile Dysfunction
- Benign Prostatic Hyperplasia
Clinical Assistant Professor, Urology
Fellowship: Stanford University Dept of Urology (2021) CA
Medical Education: University of California San Diego School of Medicine (2014) CA
Residency: University of Washington Urology Residency (2020) WA
Internship: University of Washington Dept of Surgery (2015) WA
External Device for Erectile Dysfunction (3D-Erect)
The aim of this clinical trial is to test the safety and feasibility of a non-invasive 3D-printed external penile device to achieve successful and satisfactory sexual intercourse in men with erectile dysfunction (ED).
The association between organophosphate insecticides and blood pressure dysregulation: NHANES 2013-2014.
Environmental health : a global access science source
2022; 21 (1): 74
BACKGROUND: Organophosphate (OP) insecticides represent one of the largest classes of sprayed insecticides in the U.S., and their use has been associated with various adverse health outcomes, including disorders of blood pressure regulation such as hypertension (HTN).METHODS: In a study of 935 adults from the NHANES 2013-2014 cycle, we examined the relationship between systolic and diastolic blood pressure changes and urinary concentrations of three OP insecticides metabolites, including 3,5,6-trichloro-2-pyridinol (TCPy), oxypyrimidine, and para-nitrophenol. These metabolites correspond to the parent compounds chlorpyrifos, diazinon, and methyl parathion, respectively. Weighted, multivariable linear regression analysis while adjusting for potential confounders were used to model the relationship between OP metabolites and blood pressure. Weighted, multivariable logistic regression analysis was used to model the odds of HTN for quartile of metabolites.RESULTS: We observed significant, inverse association between TCPy on systolic blood pressure (beta-estimate=-0.16, p<0.001) and diastolic blood pressure (beta-estimate=-0.15, p<0.001). Analysis with para-nitrophenol revealed a significant, positive association with systolic blood pressure (beta-estimate=0.03, p=0.02), and an inverse association with diastolic blood pressure (beta-estimate=-0.09, p<0.001). For oxypyrimidine, we observed significant, positive associations between systolic blood pressure (beta-estimate=0.58, p=0.03) and diastolic blood pressure (beta-estimate=0.31, p<0.001). Furthermore, we observed significant interactions between TCPy and ethnicity on systolic blood pressure (beta-estimate=1.46, p=0.0036). Significant interaction terms were observed between oxypyrimidine and ethnicity (beta-estimate=-1.73, p<0.001), as well as oxypyrimidine and BMI (beta-estimate=1.51 p<0.001) on systolic blood pressure, and between oxypyrimidine and age (beta-estimate=1.96, p=0.02), race (beta-estimate=-3.81 p=0.004), and BMI on diastolic blood pressure (beta-estimate=0.72, p=0.02). A significant interaction was observed between para-nitrophenol and BMI for systolic blood pressure (beta-estimate=0.43, p=0.01), and between para-nitrophenol and ethnicity on diastolic blood pressure (beta-estimate=2.19, p=0.006). Lastly, we observed a significant association between the odds of HTN and TCPy quartiles (OR=0.65, 95% CI [0.43,0.99]).CONCLUSION: Our findings support previous studies suggesting a role for organophosphate insecticides in the etiology of blood pressure dysregulation and HTN. Future studies are warranted to corroborate these findings, evaluate dose-response relationships between organophosphate insecticides and blood pressure, determine clinical significance, and elucidate biological mechanisms underlying this association.
View details for DOI 10.1186/s12940-022-00887-3
View details for PubMedID 35934697
Medical Treatment of Disorders of Ejaculation.
The Urologic clinics of North America
2022; 49 (2): 219-230
Ejaculation and orgasm are complex phenomena within the male sexual response cycle. Disordered ejaculation commonly presents as premature or delayed ejaculation, although issues with painful ejaculation, retrograde ejaculation, or postorgasmic illness syndrome are also seen. This article will review the pathophysiology of these conditions as well as the current pharmacologic treatments available.
View details for DOI 10.1016/j.ucl.2021.12.001
View details for PubMedID 35428428
The association of impaired semen quality and pregnancy rates in assisted reproduction technology cycles: Systematic review and meta-analysis.
Some studies suggest a relationship between semen quality and pregnancy rates of assisted reproduction technologies (ART). Others have questioned the utility of semen quality as proxy for fertility in couples attempting to conceive with or without assistance. We aimed to investigate the current body of evidence which correlates semen parameters and clinical pregnancy among couples utilizing ART (i.e. in vitro fertilization [IVF], intracytoplasmic sperm injection [ICSI]) through a systematic review and meta-analysis of cross-sectional and retrospective cohort studies. Pooled Odd Ratio (OR) for oligo-, astheno- and teratospermic compared to normospermic number of ART cycles were calculated among. Meta-regression and sub-group analysis were implemented to model the contribution of clinical/demographic and laboratory standards differences among the studies. Overall, 17studies were analysed representing 17,348 cycles were analysed. Pooled OR for impaired sperm concentration, motility and morphology was 1 (95%Confidence Interval [CI]: 0.97-1.03), 0.88 (95%CI: 0.73-1.03) and 0.88 (95%CI: 0.75-1) respectively. Further analysis on sperm morphology showed no differences with regard of IVF versus ICSI (p=0.14) nor a significant correlation with rising reference thresholds (Coeff: -0.02, p=0.38). A temporal trend towards a null association between semen parameters and clinical pregnancy was observed over the 20-year observation period (Coeff: 0.01, p=0.014). The current analysis found no association between semen quality (as measured by concentration, motility or morphology) and clinical pregnancy rates utilizing ART. Future investigations are necessary to explore the association between semen parameters and other ART outcomes (e.g. fertilization, implantation, birth and perinatal health).
View details for DOI 10.1111/and.14409
View details for PubMedID 35244232
Male fertility as a marker for health.
Reproductive biomedicine online
Male reproduction is a complex biological process, and male factor infertility is increasingly recognized as a biomarker for overall male health. Emerging data suggest associations between male reproduction and medical disease (genetic, infectious, chronic comorbid conditions), psychological disease, environmental exposures, dietary habits, medications and substances of abuse, and even socioeconomic factors. There is also evidence that a diagnosis of male fertility is associated with future disease risk including cancer, metabolic disease and mortality. As such, there is a growing view that the male fertility evaluation is an opportunity to improve a man's health beyond his immediate reproductive goals, and also highlights the necessity of a multidisciplinary approach.
View details for DOI 10.1016/j.rbmo.2021.09.023
View details for PubMedID 34848151
THE ASSOCIATION OF PRECONCEPTION PATERNAL METABOLIC SYNDROME ON EARLY CHILDHOOD EMERGENCY DEPARTMENT VISITS AND HOSPITALIZATION: ANALYSIS OF US CLAIMS DATA
LIPPINCOTT WILLIAMS & WILKINS. 2021: E526
View details for Web of Science ID 000693688500311
ASSOCIATIONS BETWEEN RACE AND ERECTILE DYSFUNCTION TREATMENT PATTERNS
LIPPINCOTT WILLIAMS & WILKINS. 2021: E1172
View details for Web of Science ID 000693689000836
Trends in Testosterone Therapy use in Prostate Cancer Survivors in the United States.
The journal of sexual medicine
BACKGROUND: Physician prescribing patterns surrounding the use of testosterone therapy (TTh) in men with a history of prostate cancer (CaP) is not well described.AIM: To characterize the demographics and usage patterns of testosterone therapy in men with a history of prostate cancer in the United States.METHODS: This was a retrospective review using Optum's De-identified Clinformatics Data Mart database. Administrative diagnosis, procedural, pharmacy, and laboratory codes were used to identify male subjects 40 years and older with prostate cancer treated with surgery or radiation between 2003 and 2018 who went on to receive TTh. Demographic and clinical factors are identified. Temporal trends in TTh usage were reported.OUTCOMES: The main outcomes were rates of testosterone prescriptions in men with treated prostate cancer and associated laboratory values such as Prostate Specific Antigen (PSA) and testosterone levels before TTh.RESULTS: 126,374 men completed treatment for CaP during the study period (42,515 surgery, 75,186 radiation, 8,673 both). Of these, 3,074 men (2.4%) received testosterone after CaP treatment. Men who received testosterone were younger, more likely to have erectile dysfunction, depressive disorder, and lower pretreatment PSA values compared to men who did not receive. Median PSA levels before TTh initiation were 0 - 0.2 depending on CaP treatment modality and median total testosterone level was <300 ng/dL. TTh began an average of 1.5 years after radical prostatectomy and 2.6 years after radiation treatment. We observed an increase in TTh after CaP from the beginning of the study period until it peaked in 2013 at 4.9%. After 2013, rates decreased annually until a plateau of approximately 1.8% of men. Approximately a third of men did not have testosterone labs checked before initiation of TTh.CLINICAL IMPLICATIONS: These findings provide insight into trends in testosterone prescriptions in men after prostate cancer treatment and may aid in clinical decision-making, as well as areas for improvement in cancer survivorship care.STRENGTHS AND LIMITATIONS: Strengths include the large sample size, length of data coverage, and real-world analysis of testosterone prescribing patterns across the United States. Limitations include the reliance on insurance claims data, the retrospective study design, and lack of additional relevant clinical variables that may impact decision making regarding TTh.CONCLUSION: National trends in testosterone prescriptions for men with treated prostate cancer suggest that many men are treated with TTh after prostate cancer therapy with patterns of indications and monitoring consistent with the general population. Chen T, Li S, Eisenberg M. Trends in Testosterone Therapy use in Prostate Cancer Survivors in the United States. J Sex Med 2021;XX:XXX-XXX.
View details for DOI 10.1016/j.jsxm.2021.06.007
View details for PubMedID 34303630
The Association Between Hemoglobin A1c Levels and Inflatable Penile Prosthesis Infection: Analysis of US Insurance Claims Data.
The journal of sexual medicine
BACKGROUND: The association between elevated hemoglobin A1c (HbA1c) levels and the risk of postoperative infection after penile prosthesis surgery remains controversial.AIM: To examine the association between HbA1c levels and penile implant infections in men undergoing inflatable penile prosthesis (IPP) surgery for erectile dysfunction using a large insurance claims database.METHODS: This was a retrospective review using Optum's de-identified Clinformatics Data Mart Database. Male subjects 18 years and older with available laboratory data undergoing IPP insertion between 2003 and 2018 were included. Administrative diagnosis and procedural codes were used to assess subsequent penile implant revision surgery status for either infectious or noninfectious causes. Associated conditions were controlled for such as smoking status, hyperlipidemia, hypertension, obesity status, and Peyronie's disease.OUTCOMES: The main outcomes were risk of revision for infection and time to revision.RESULTS: A total of 2,363 individuals underwent initial IPP insertion and had available HbA1c data with a mean HbA1c of 6.9%. The overall IPP infection revision rate was 3.9% and the highest rate of 12.1% was seen in the highest HbA1c group (>10%). After adjusting for demographic and health factors, a higher HbA1c level was associated with a higher risk of revision for infection, with every 1 point increase in HbA1c conferring an increased risk of infection requiring revision by 29% (95% CI 17-42%). When infections did occur, they happened sooner in men with HbA1c > 10.0% with an average of 1.3 months vs 3.5 months in the HbA1c < 6.0% group.CLINICAL IMPLICATIONS: These findings provide insight into the potential relationship between HbA1c levels and postoperative risk of infection after penile prosthesis surgery and may aid in clinical decision-making.STRENGTHS AND LIMITATIONS: Strengths include the large sample size, length of data coverage, and real-world analysis of surgeries done across the United States. Limitations include the reliance on insurance claims data, the retrospective study design, and lack of additional relevant clinical variables that may impact infection rates.CONCLUSIONS: While the overall risk of penile prosthesis infection remains modest, the current report notes an increased risk of infection for diabetic men with poor glycemic control. Chen T, Li S, Eisenberg ML. The Association Between Hemoglobin A1c Levels and Inflatable Penile Prosthesis Infection: Analysis of US Insurance Claims Data. J Sex Med 2021;18:1104-1109.
View details for DOI 10.1016/j.jsxm.2021.03.077
View details for PubMedID 34103256
Female Sexual Function During the COVID-19 Pandemic in the United States.
2021; 9 (4): 100355
INTRODUCTION: International studies have demonstrated increasing rates of sexual dysfunction amidst the coronavirus disease 2019 (COVID-19) pandemic; however, the impact of the pandemic on female sexual function in the United States is unknown.AIM: To assess the impact of the COVID-19 pandemic on female sexual function and frequency in the United States.METHODS: A pre-pandemic survey containing the Female Sexual Function Index (FSFI) and demographic questions was completed by adult women in the United States from October 20, 2019 and March 1, 2020. The same women were sent a follow-up survey also containing the FSFI, as well as the Patient Health Questionnaire for Depression and Anxiety with 4 items (PHQ-4), and questions pertaining to mask wearing habits, job loss, and relationship changes. Risk for female sexual dysfunction (RFSD) was defined as FSFI < 26.55.MAIN OUTCOME MEASURE: Differences in pre-pandemic and intra-pandemic female sexual function, measured by the FSFI, and sexual frequency.RESULTS: Ninety-one women were included in this study. Overall FSFI significantly decreased during the pandemic (27.2 vs 28.8, P=.002), with domain-specific decreases in arousal (4.41 vs 4.86, P=.0002), lubrication (4.90 vs 5.22, P=.004), and satisfaction (4.40 vs 4.70, P=.04). There was no change in sexual frequency. Contingency table analysis of RFSD prior to and during the pandemic revealed significantly increased RFSD during the pandemic (P=.002). Women who developed RFSD during the pandemic had higher PHQ-4 anxiety subscale scores (3.74 vs 2.53, P=.01) and depression subscale scores (2.74 vs 1.43, P=.001) than those who did not. Development of FSD was not associated with age, home region, relationship status, mask wearing habits, knowing someone who tested positive for COVID-19, relationship change, or job loss and/or reduction during the pandemic.CONCLUSION: In this population of female cannabis users, risk for sexual dysfunction increased amidst the COVID-19 pandemic and is associated with depression and anxiety symptoms. Bhambhvani HP, Chen T, Wilson-King AM, etal. Female Sexual Function During the COVID-19 Pandemic in the United States. Sex Med 2021;9:100355.
View details for DOI 10.1016/j.esxm.2021.100355
View details for PubMedID 34174585
Association of daily step count and serum testosterone among men in the United States.
PURPOSE: To describe the association between daily activity (i.e., daily step counts and accelerometer intensity measures) and serum TT levels in a representative sample of US adults aged 18 years or older.METHODS: A retrospective cohort study was carried out utilizing the NHANES (National Health and Nutrition Examination Survey) 2003-2004 cycle. Physical activity was measured with a waist-worn uniaxial accelerometer (AM-7164; ActiGraph) for up to 7 days using a standardized protocol. Using linear and multivariable logistic regression controlling for relevant social, demographic, lifestyle, and comorbidity characteristics, we assessed the association between daily step counts and TT.RESULTS: A total of 279 subjects with a median age 46 (IQR: 33-56) were included in the analysis. 23.3% of the cohort had a low serum TT level (TT<350ng/dl). Compared to men who took <4000 steps per day, men who took >4000 or >8000 steps/day had a lower odd of being hypogonadal (OR 0.14, 95% CI: 0.07-0.49 and 0.08, 95%CI: 0.02-0.44, respectively). While a threshold effect was noted on average, TT increased 7ng/dL for each additional 1000 steps taken daily (beta-estimate: 0.007, 95% CI: 0.002-0.013).CONCLUSIONS: Patients with the lowest daily step counts had higher odds of being hypogonadal. The current work supports a possible association between daily steps, total testosterone, and hypogonadism for men in the US.
View details for DOI 10.1007/s12020-021-02631-2
View details for PubMedID 33580402
The Association of the COVID-19 Pandemic on Male Sexual Function in the United States: A Survey Study of Male Cannabis Users.
2021; 9 (3): 100340
International studies have suggested that social disruptions caused by the COVID-19 pandemic have led to sexual dysfunction, but the impact on males in the United States is less defined.To examine changes in male sexual function during the COVID-19 pandemic and to evaluate associated demographic variables.Prepandemic survey data was collected between October 20, 2019 and March 1, 2020 on adult males in the United States. Follow-up survey data collected for comparison during the COVID-19 pandemic between August 1, 2020 and October 10, 2020 included International Index of Erectile Function (IIEF) scores, Patient Health Questionnaire for Depression and Anxiety with 4 items (PHQ-4) scores, and questions regarding sexual frequency. Questions were also asked about mask-wearing habits, job loss, relationship changes, and proximity to individuals who tested positive for COVID-19.Differences in prepandemic and pandemic male sexual function assessed by self-reported IIEF domain scores and sexual frequency RESULTS: Seventy six men completed both prepandemic and pandemic surveys with a mean age of 48.3 years. Overall, there were no differences in either overall IIEF score or any subdomain score when comparing men's pre-pandemic and pandemic survey data. There was an increase in sexual frequency during the pandemic with 45% of men reporting sex ten or more times per month during the pandemic compared to only 25% of men prior to the pandemic (P = .03). Among the subgroup of 36 men who reported a decrease in IIEF, the decrease was an average of 3.97, and significantly associated with higher PHQ-4 depression subscale scores (1.78 vs 1.03, P = .02).The COVID-19 pandemic is associated with increased sexual frequency and no change in overall sexual function in males in the United States. Interventions intended to promote male sexual health during the COVID-19 pandemic should include a focus on mental health. T Chen, HP Bhambhvani, AM Kasman, et al. The Association of the COVID-19 Pandemic on Male Sexual Function in the United States: A Survey Study of Male Cannabis Users. J Sex Med 2021;XX:XXX-XXX.
View details for DOI 10.1016/j.esxm.2021.100340
View details for PubMedID 33789175
The Association between Mortality and Male Infertility: Systematic Review and Meta-analysis.
To summarize the current body of evidence on the relationship between impaired male fertility and the risk of early death through a systematic review and meta-analysis of population-based retrospective cohort studies.PubMed, Web of Science, Embase, Cochrane Library, and Scopus databases were searched from inception to August 2020 according to the Meta-analysis Of Observational Studies in Epidemiology (MOOSE) guidelines. Pooled Risk Ratio (RR), Risk Difference (Δr), Hazard Ratio (HR) and Standardized Mortality Ratio (SMR) differences among male factor infertility cohorts were compared to fertile/normospermic control populations or to national mortality data.Six studies from 2006 to 2020 met inclusion criteria. Three studies examined male infertility and mortality (ntot=202,456; ndeaths=1396), while four studies examined survival in relation to semen parameters (ntot= 59,291; ndeaths= 643). Comparing infertile to fertile men, pooled HR for the risk of death was 1.26 (95%CI:1.01-1.59). Pooled RR and Δr of death for combined oligo- and azoospermic men vs. normospermic men was 1.67 (95%CI:1.26-2.21) and 0.37% (95%CI:0.18-0.55%) respectively. When comparing oligo- and normospermic men to azoospermic men, the cumulative HR was 1.31 (95%CI:1.11-1.54) and 2.17 (95%CI:1.55-3.04) respectively. Infertile men had a lower overall risk of death compared to the overall population (SMR, 0.38, 95%CI:0.31-0.45).Compared to fertile men, infertile men had a higher risk of death. Moreover, the risk of death increased with increasing severity of semen quality impairment. However, compared to men from the general population, infertile men have a lower risk of death suggesting that social determinants of health are also important.
View details for DOI 10.1016/j.urology.2021.02.041
View details for PubMedID 33819517
- Challenges in Survey-Based Research. The journal of sexual medicine 2020