Linn Håkonsen Arendt1,2, Cecilia Høst Ramlau-Hansen1, Morten Søndergaard Lindhard2, Tine Brink Henriksen2, Jørn Olsen1,3, Yongfu Yu3, Sven Cnattingius4. 1. Department of Public Health, Section for Epidemiology, Aarhus University, Aarhus, Denmark. 2. Perinatal Epidemiology Research Unit, Department of Child and Adolescent Health, Aarhus University Hospital, Aarhus, Denmark. 3. Department of Clinical Epidemiology, Aarhus University Hospital, Aarhus, Denmark. 4. Clinical Epidemiology Unit, Department of Medicine, Karolinska University Hospital, Stockholm, Sweden.
Abstract
BACKGROUND: Overweight and obese pregnant women face higher risk of several critical birth outcomes, including an overall increased risk of congenital abnormalities. Only few studies have focused on associations between maternal overweight and the genital anomalies in boys, cryptorchidism and hypospadias, and results are inconclusive. METHODS: We performed a population-based cohort study and assessed the associations between maternal body mass index (BMI) in early pregnancy and occurrence of cryptorchidism and hypospadias. All live-born singleton boys born in Sweden from 1992 to 2012 were included. From the Swedish Patient Register, information on cryptorchidism and hypospadias was available. Data were analysed using Cox proportional hazards regression adjusted for potential confounders. Mediation analyses were performed to estimate how much of the association between BMI and genital anomalies were mediated through obesity-related diseases. RESULTS: Of the 1 055 705 live-born singleton boys born from 1992 to 2012, 6807 (6.4 per 1000) were diagnosed with hypospadias and 16 469 (15.6 per 1000) were diagnosed with cryptorchidism, of which 9768 (9.3 per 1000) underwent corrective surgery for cryptorchidism. We observed dose-response associations between maternal BMI and hypospadias and cryptorchidism. Boys of mothers with BMI ≥40.0 kg/m2 had the highest adjusted hazard ratios for hypospadias (HR 1.35, 95% confidence interval [CI] 1.04, 1.76) and cryptorchidism (HR 1.25, 95% CI 1.00, 1.58). A substantial proportion of the associations between BMI and the genital anomalies were mediated through preeclampsia. CONCLUSION: This large register-based study adds to the current literature and indicates that the occurrence of hypospadias and cryptorchidism increase with maternal overweight and obesity severity.
BACKGROUND: Overweight and obese pregnant women face higher risk of several critical birth outcomes, including an overall increased risk of congenital abnormalities. Only few studies have focused on associations between maternal overweight and the genital anomalies in boys, cryptorchidism and hypospadias, and results are inconclusive. METHODS: We performed a population-based cohort study and assessed the associations between maternal body mass index (BMI) in early pregnancy and occurrence of cryptorchidism and hypospadias. All live-born singleton boys born in Sweden from 1992 to 2012 were included. From the Swedish Patient Register, information on cryptorchidism and hypospadias was available. Data were analysed using Cox proportional hazards regression adjusted for potential confounders. Mediation analyses were performed to estimate how much of the association between BMI and genital anomalies were mediated through obesity-related diseases. RESULTS: Of the 1 055 705 live-born singleton boys born from 1992 to 2012, 6807 (6.4 per 1000) were diagnosed with hypospadias and 16 469 (15.6 per 1000) were diagnosed with cryptorchidism, of which 9768 (9.3 per 1000) underwent corrective surgery for cryptorchidism. We observed dose-response associations between maternal BMI and hypospadias and cryptorchidism. Boys of mothers with BMI ≥40.0 kg/m2 had the highest adjusted hazard ratios for hypospadias (HR 1.35, 95% confidence interval [CI] 1.04, 1.76) and cryptorchidism (HR 1.25, 95% CI 1.00, 1.58). A substantial proportion of the associations between BMI and the genital anomalies were mediated through preeclampsia. CONCLUSION: This large register-based study adds to the current literature and indicates that the occurrence of hypospadias and cryptorchidism increase with maternal overweight and obesity severity.
Authors: Melissa A Richard; Pagna Sok; Stephen Canon; Wendy N Nembhard; Austin L Brown; Erin C Peckham-Gregory; Minh Ton; Erik A Ehli; Noah A Kallsen; Shanna A Peyton; Gareth E Davies; Ashay Patel; Ismael Zamilpa; Charlotte A Hobbs; Michael E Scheurer; Philip J Lupo Journal: Sci Rep Date: 2020-07-29 Impact factor: 4.379