Giulia Scaravelli1, Valerio Pisaturo2, Paolo Emanuele Levi Setti3,4, Filippo Maria Ubaldi5, Claudia Livi6, Andrea Borini7, Ermanno Greco8,9, Maria Teresa Villani10, Maria Elisabetta Coccia11, Alberto Revelli12, Giuseppe Ricci13,14, Francesco Fusi15, Mauro Costa16, Emanuela Migliorati17, Roberto De Luca1, Vincenzo Vigiliano1, Simone Bolli1, Marco Reschini18. 1. ART Italian National Register, National Center for Diseases Prevention and Health Promotion, National Health Institute, Rome, Italy. 2. Infertility Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via M. Fanti 6, 20122, Milan, Italy. valerio.pisaturo@policlinico.mi.it. 3. Department of Gynecology, Division of Gynecology and Reproductive Medicine, Fertility Center, IRCCS Humanitas Research Hospital, Rozzano (Milan), Italy. 4. Department of Biomedical Sciences, Humanitas University, Milan, Italy. 5. Clinica Valle Giulia, GeneraLife IVF, Rome, Italy. 6. Demetra GeneraLife Assisted Procreation Center, Florence, Italy. 7. 9.baby - GeneraLife, Bologna, Italy. 8. Villa Mafalda, Rome, Italy. 9. UniCamillus, International Medical University, Rome, Italy. 10. Department of Obstetrics and Gynaecology, Fertility Centre, Arcispedale Santa Maria Nuova, Azienda Unità Sanitaria Locale-IRCCS di Reggio Emilia, Reggio Emilia, Italy. 11. Assisted Reproductive Center, Careggi Hospital, University of Florence, Florence, Italy. 12. Gynecology and Obstetrics 1U/2U, Physiopathology of Reproduction and IVF Unit, Sant'Anna Hospital, University of Torino, Turin, Italy. 13. Department of Obstetrics and Gynecology, Institute for Maternal and Child Health, IRCCS Burlo Garofolo, Trieste, Italy. 14. Department of Medicine, Surgery and Health Sciences, University of Trieste, Trieste, Italy. 15. Department of Maternal Fetal and Pediatric Medicine, ASST, Papa Giovanni XXIII, Bergamo, Italy. 16. Department of Reproductive Medicine, Ospedale Evangelico Internazionale, Genoa, Italy. 17. Surgery for Gynecology and Obstetrics, Genera Umbria S.R.L, Umbertide, Perugia, Italy. 18. Infertility Unit, Fondazione IRCCS Ca' Granda Ospedale Maggiore Policlinico, Via M. Fanti 6, 20122, Milan, Italy.
Abstract
PURPOSE: The risk of monozygotic twins (MZTs) is increased in couples undergoing assisted reproductive technology (ART) treatments. Several systematic reviews have investigated the possible determinants linked to ART, but results obtained have not been conclusive. The study aims to investigate whether the incidence of MZT differed among ART centers. METHODS: This is a multicenter retrospective cohort study using the Italian ART National Registry database and involving the centers reporting data from individual ART cycles from 2015 to 2019. To investigate the incidence of MZT, only single embryo transfer cycles were considered. Women who had sex-discordant deliveries were excluded. MZT rate was calculated as the number of multiple pregnancies (more than one gestational sac at first ultrasound) out of the total number of clinical pregnancies. A binomial distribution model was used to determine the 95% CI of the frequency of MZT. RESULTS: Eighteen centers were included, and they provided data on 10,433 pregnancies. The total number of MZT was 162, corresponding to an incidence of 1.5% (95% CI: 1.3-1.8%). The rate of MZT among centers varied between 0% (95% CI: 0.0-25.9%) and 3.2% (95% CI: 1.3-8.1%). All the 95% CIs included 1.5%, rejecting the hypothesis that the MZT rate may significantly differ among centers. CONCLUSIONS: The rate of MZT did not significantly vary among ART centers. Local factors are unlikely to explain the increased rate of MZT in ART pregnancies.
PURPOSE: The risk of monozygotic twins (MZTs) is increased in couples undergoing assisted reproductive technology (ART) treatments. Several systematic reviews have investigated the possible determinants linked to ART, but results obtained have not been conclusive. The study aims to investigate whether the incidence of MZT differed among ART centers. METHODS: This is a multicenter retrospective cohort study using the Italian ART National Registry database and involving the centers reporting data from individual ART cycles from 2015 to 2019. To investigate the incidence of MZT, only single embryo transfer cycles were considered. Women who had sex-discordant deliveries were excluded. MZT rate was calculated as the number of multiple pregnancies (more than one gestational sac at first ultrasound) out of the total number of clinical pregnancies. A binomial distribution model was used to determine the 95% CI of the frequency of MZT. RESULTS: Eighteen centers were included, and they provided data on 10,433 pregnancies. The total number of MZT was 162, corresponding to an incidence of 1.5% (95% CI: 1.3-1.8%). The rate of MZT among centers varied between 0% (95% CI: 0.0-25.9%) and 3.2% (95% CI: 1.3-8.1%). All the 95% CIs included 1.5%, rejecting the hypothesis that the MZT rate may significantly differ among centers. CONCLUSIONS: The rate of MZT did not significantly vary among ART centers. Local factors are unlikely to explain the increased rate of MZT in ART pregnancies.
Authors: S Marleen; C Dias; R Nandasena; R MacGregor; J Allotey; J Aquilina; A Khalil; S Thangaratinam Journal: BJOG Date: 2020-10-07 Impact factor: 6.531
Authors: Jennifer F Knudtson; Randal D Robinson; Amy E Sparks; Micah J Hill; T Arthur Chang; Bradley J Van Voorhis Journal: Fertil Steril Date: 2021-10-18 Impact factor: 7.329