Anna-Karina A Henningsen1, Christina Bergh2, Rolv Skjaerven3,4, Aila Tiitinen5, Ulla-Britt Wennerholm6, Liv B Romundstad7,8,9, Mika Gissler10,11, Signe Opdahl8,9, Anders Nyboe Andersen1, Øjvind Lidegaard12, Julie L Forman13, Anja Pinborg14. 1. Fertility Clinic, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. 2. Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, University of Gothenburg, Reproductive Medicine, Sahlgrenska University Hospital, Gothenburg, Sweden. 3. Department of Global Public Health and Primary Health Care, University of Bergen, Bergen, Norway. 4. Medical Birth Registry of Norway, Norwegian Institute of Public Health, Bergen, Norway. 5. Department of Obstetrics and Gynecology, University of Helsinki, Helsinki University Hospital, Helsinki, Finland. 6. Perinatal Center, Department of Obstetrics and Gynecology, Institute of Clinical Sciences, Sahlgrenska Academy, Gothenburg University, Sahlgrenska University Hospital/East, Gothenburg, Sweden. 7. Spiren Fertility Clinic, Trondheim, Norway. 8. Central Norway Regional Health Authority, Stjørdal, Norway. 9. Department of Public Health and General Practice, Norwegian University of Science and Technology, Trondheim, Norway. 10. National Institute for Health and Welfare (THL), Helsinki, Finland. 11. Department of Neurobiology, Care Sciences and Society, Division of Family Medicine, Karolinska Institute, Stockholm, Sweden. 12. Gynecological Clinic, Rigshospitalet, University of Copenhagen, Copenhagen, Denmark. 13. Section of Biostatistics, Department of Public Health, University of Copenhagen, Copenhagen, Denmark. 14. Department of Obstetrics and Gynecology, Hvidovre Hospital, University of Copenhagen, Copenhagen, Denmark.
Abstract
INTRODUCTION: Children born after assisted reproductive technology, particularly singletons, have been shown to have an increased risk of congenital malformations compared with children born after spontaneous conception. We wished to study whether there has been a change in the past 20 years in the risk of major congenital malformations in children conceived after assisted reproductive technology compared with children spontaneously conceived. MATERIAL AND METHODS: Population-based cohort study including 90 201 assisted reproductive technology children and 482 552 children spontaneously conceived, born in Denmark, Finland, Norway and Sweden. Both singletons and twins born after in vitro fertilization, intracytoplasmatic sperm injection and frozen embryo transfer were included. Data on children were taken from when the national Nordic assisted reproductive technology registries were established until 2007. Multiple logistic regression analyses were used to estimate the risks and adjusted odds ratios for congenital malformations in four time periods: 1988-1992, 1993-1997, 1998-2002 and 2003-2007. Only major malformations were included. RESULTS: The absolute risk for singletons of being born with a major malformation was 3.4% among assisted reproductive technology children vs. 2.9% among children spontaneously conceived during the study period. The relative risk of being born with a major congenital malformation between all assisted reproductive technology children and children spontaneously conceived remained similar through all four time periods (p = 0.39). However, we found that over time the number of children diagnosed with a major malformation increased in both groups across all four time periods. CONCLUSION: When comparing children conceived after assisted reproductive technology and spontaneously conceived, the relative risk of being born with a major congenital malformation did not change during the study period.
INTRODUCTION:Children born after assisted reproductive technology, particularly singletons, have been shown to have an increased risk of congenital malformations compared with children born after spontaneous conception. We wished to study whether there has been a change in the past 20 years in the risk of major congenital malformations in children conceived after assisted reproductive technology compared with children spontaneously conceived. MATERIAL AND METHODS: Population-based cohort study including 90 201 assisted reproductive technology children and 482 552 children spontaneously conceived, born in Denmark, Finland, Norway and Sweden. Both singletons and twins born after in vitro fertilization, intracytoplasmatic sperm injection and frozen embryo transfer were included. Data on children were taken from when the national Nordic assisted reproductive technology registries were established until 2007. Multiple logistic regression analyses were used to estimate the risks and adjusted odds ratios for congenital malformations in four time periods: 1988-1992, 1993-1997, 1998-2002 and 2003-2007. Only major malformations were included. RESULTS: The absolute risk for singletons of being born with a major malformation was 3.4% among assisted reproductive technology children vs. 2.9% among children spontaneously conceived during the study period. The relative risk of being born with a major congenital malformation between all assisted reproductive technology children and children spontaneously conceived remained similar through all four time periods (p = 0.39). However, we found that over time the number of children diagnosed with a major malformation increased in both groups across all four time periods. CONCLUSION: When comparing children conceived after assisted reproductive technology and spontaneously conceived, the relative risk of being born with a major congenital malformation did not change during the study period.