Advertisement

Not all twins are monozygotic after elective single embryo transfer: analysis of 32,600 elective single embryo transfer cycles as reported to the Society for Assisted Reproductive Technology

  • Mario Vega
    Affiliations
    Albert Einstein College of Medicine, Department of Obstetrics/Gynecology and Women's Health, Bronx, New York

    Montefiore's Institute for Reproductive Medicine and Health, Hartsdale, New York
    Search for articles by this author
  • Sahar Zaghi
    Affiliations
    Albert Einstein College of Medicine, Department of Obstetrics/Gynecology and Women's Health, Bronx, New York
    Search for articles by this author
  • Erkan Buyuk
    Affiliations
    Albert Einstein College of Medicine, Department of Obstetrics/Gynecology and Women's Health, Bronx, New York

    Montefiore's Institute for Reproductive Medicine and Health, Hartsdale, New York
    Search for articles by this author
  • Sangita Jindal
    Correspondence
    Reprint requests: Sangita Jindal, Ph.D., H.C.L.D., Montefiore's Institute for Reproductive Medicine and Health, 141 South Central Avenue, Suite 201, Hartsdale, New York, 10530.
    Affiliations
    Albert Einstein College of Medicine, Department of Obstetrics/Gynecology and Women's Health, Bronx, New York

    Montefiore's Institute for Reproductive Medicine and Health, Hartsdale, New York
    Search for articles by this author

      Objective

      To study the incidence and risk factors of multiple pregnancies after elective single ET.

      Design

      Historic cohort.

      Setting

      Not applicable.

      Patient(s)

      Women <35 years of age undergoing elective single ET entered in the SART CORS database from 2010 to 2013.

      Interventions

      Not applicable.

      Main Outcome Measure(s)

      Rate of sex discordant pregnancies. Rate of same sex pregnancies and risk factors for both same sex and sex discordant pregnancies.

      Result(s)

      A total of 32,600 cycles were reported to SART CORS during this time period. There were 15,143 pregnancies from which 14,888 were singletons (98.3%), 23 sex discordant (0.15%) multiple pregnancies, 226 (1.5%) sex concordant multiple pregnancies, and 6 (0.01%) pregnancies without sex information. When Weinberg's differential rule was applied, the rate of dizygotic pregnancies was calculated to be 18%. Unexplained infertility was found to be the biggest risk factor for sex discordant multiple pregnancies (adjusted odds ratio 4.33, 95% confidence interval 1.4–13.1), followed by elevated body mass index (BMI). The only risk factor found for sex concordant pregnancies was undergoing a fresh transfer (adjusted odds ratio 1.4, 95% confidence interval 1.02–1.95).

      Conclusion(s)

      Elective single ET improves, but does not completely eliminate the risk of multiple pregnancies. Patients should be counseled that there might be up to a ∼2% risk of multiple pregnancies, of which up to 18% can be dizygotic. Patients with elevated BMI and unexplained fertility may be at higher risk for sex discordant multiple pregnancies and patients undergoing fresh cycles may be at higher risk for sex concordant multiple pregnancies.

      Key Words

      To read this article in full you will need to make a payment

      References

        • Martin J.A.
        • Hamilton B.E.
        • Osterman M.J.
        Three decades of twin births in the United States, 1980-2009.
        NCHS Data Brief. 2012; 80: 1-8
        • Vitthala S.
        • Gelbaya T.A.
        • Brison D.R.
        • Fitzgerald C.T.
        • Nardo L.G.
        The risk of monozygotic twins after assisted reproductive technology: a systematic review and meta-analysis.
        Hum Reprod Update. 2009; 15: 45-55
        • Garg P.
        • Abdel-Latif M.E.
        • Bolisetty S.
        • Bajuk B.
        • Vincent T.
        • Lui K.
        Perinatal characteristics and outcome of preterm singleton, twin and triplet infants in NSW and the ACT, Australia (1994-2005).
        Arch Dis Child Fetal Neonatal Ed. 2010; 95: F20-F24
        • Wen S.W.
        • Demissie K.
        • Yang Q.
        • Walker M.C.
        Maternal morbidity and obstetric complications in triplet pregnancies and quadruplet and higher-order multiple pregnancies.
        Am J Obstet Gynecol. 2004; 191: 254-258
        • Blickstein I.
        • Jones C.
        • Keith L.G.
        Zygotic-splitting rates after single-embryo transfers in in vitro fertilization.
        N Engl J Med. 2003; 348: 2366-2367
        • Kanter J.R.
        • Boulet S.L.
        • Kawwass J.F.
        • Jamieson D.J.
        • Kissin D.M.
        Trends and correlates of monozygotic twinning after single embryo transfer.
        Obstet Gynecol. 2015; 125: 111-117
        • Mateizel I.
        • Santos-Ribeiro S.
        • Done E.
        • van Landuyt L.
        • van de Velde H.
        • Tournaye H.
        • et al.
        Do ARTs affect the incidence of monozygotic twinning?.
        Hum Reprod. 2016; 31: 2435-2441
        • Blickstein I.
        Estimation of iatrogenic monozygotic twinning rate following assisted reproduction: pitfalls and caveats.
        Am J Obstet Gynecol. 2005; 192: 365-368
        • Osianlis T.
        • Rombauts L.
        • Gabbe M.
        • Motteram C.
        • Vollenhoven V.
        Incidence and zygosity of twin births following transfers using a single fresh or frozen embryo.
        Hum Reprod. 2014; 29: 1438-1443
        • Centers for Disease Control and Prevention, ASfRM, and Society for Assisted Reproductive Technology
        2012 Assisted reproductive technology success rates: national summary and fertility clinic reports.
        US Dept of Health and Human Services, Washington, DC2014
        • Fellman J.
        • Eriksson A.W.
        Weinberg's differential rule reconsidered.
        Hum Biol. 2006; 78: 253-275
        • Collins J.A.
        • Burrows E.A.
        • Wilan A.R.
        The prognosis for live birth among untreated infertile couples.
        Fertil Steril. 1995; 64: 22-28
        • Provost M.P.
        • Acharya K.S.
        • Acharya C.R.
        • Yeh J.S.
        • Steward R.G.
        • Eaton J.L.
        • et al.
        Pregnancy outcomes decline with increasing recipient body mass index: an analysis of 22,317 fresh donor/recipient cycles from the 2008-2010 Society for Assisted Reproductive Technology Clinic Outcome Reporting System registry.
        Fertil Steril. 2016; 105: 364-368
        • Aston K.I.
        • Peterson C.M.
        • Carrell D.T.
        Monozygotic twinning associated with assisted reproductive technologies: a review.
        Reproduction. 2008; 136: 377-386
        • Knopman J.M.
        • Krey L.C.
        • Oh C.
        • Lee J.
        • McCaffrey C.
        • Noyes N.
        What makes them split? Identifying risk factors that lead to monozygotic twins after in vitro fertilization.
        Fertil Steril. 2014; 102: 82-89
        • Wright V.
        • Schieve L.A.
        • Vahratian A.
        • Reynolds M.A.
        Monozygotic twinning associated with day 5 embryo transfer in pregnancies conceived after IVF.
        Hum Reprod. 2004; 19: 1831-1836
        • Kawachiya S.
        • Bodri D.
        • Shimada N.
        • Kato K.
        • Takehara Y.
        • Kato O.
        Blastocyst culture is associated with an elevated incidence of monozygotic twinning after single embryo transfer.
        Fertil Steril. 2011; 95: 2140-2142
        • Sills E.S.
        • Moomjy M.
        • Zaninovic N.
        • Veeck L.L.
        • McGee M.
        • Palermo G.D.
        • et al.
        Human zona pellucida micromanipulation and monozygotic twinning frequency after IVF.
        Hum Reprod. 2000; 15: 890-895
        • Papanikolaou E.G.
        • Fatemi H.
        • Venetis C.
        • Donoso P.
        • Kolibianakis E.
        • Tournaye H.
        • et al.
        Monozygotic twinning is not increased after single blastocyst transfer compared with single cleavage-stage embryo transfer.
        Fertil Steril. 2010; 93: 592-597