Lower risks of adverse outcome in twins conceived by artificial reproductive techniques compared with spontaneously conceived twins

Department of Obstetrics and Gynaecology, Jichi Medical School, Tochigi, Japan.
Human Reproduction (Impact Factor: 4.57). 08/1998; 13(7):2005-8. DOI: 10.1093/humrep/13.7.2005
Source: PubMed


The outcomes of twins conceived by 136 women after medical assistance (MA) such as ovulation induction with or without assisted reproductive techniques, and twins conceived spontaneously (SP) by 72 women were compared. All 208 women were monitored from < 20 weeks gestation; they all delivered at > or = 24 weeks gestation. The chorionicity of the placenta was diagnosed antenatally and confirmed after delivery. There were 10 perinatal deaths; the physical and neurological status of the remaining 406 infants was assessed at 1 year of corrected age. There were no differences in gestational age at birth, the birth weights of the larger and smaller twins, the birth weight discordance, or the incidence of life-threatening major malformations between groups. Adverse infant outcomes, such as death, cerebral palsy and mental retardation occurred in nine (3.3%) of 272 MA twins compared with 12 (8.3%) of 144 SP twins (P < 0.05). The placenta was monochorionic in only three (2.2%) of 136 MA twin pregnancies compared with 41 (57%) of 72 SP twin pregnancies (P < 0.001). Of the 21 infants with adverse outcomes, nine had monochorionic placentas. Thus, the risk of an adverse outcome was 2.8-fold higher (95% confidence interval (CI) 1.2-6.4) in monochorionic twins than in dichorionic twins (10 versus 3.7%; P < 0.05). There was no difference in the incidence of adverse infant outcomes between SP (4.8%) and MA (3.4%) twins with dichorionic placentas. These findings suggest that ovulation induction in itself was not associated with an adverse outcome of twin pregnancies. The lower frequency of monochorionic placentas in MA twins may have been responsible for the lower risk of an adverse outcome in MA twins.

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Available from: Hisanori Minakami
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    • "This is in agreement with the Swedish study, where IVF singletons carried an increased risk of cerebral palsy 2.8 (1.3–5.8) as compared with singletons from the general population (Strömberg et al., 2002). Two other controlled studies have assessed neurological sequel in IVF twins with sample size between 94 and 272, which is too small to draw valid conclusions (Saunders et al., 1996; Minakami et al., 1998). "
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    ABSTRACT: Since the 1970s, the national twin birth rates have been increasing worldwide. Apart from the increasing childbearing age, the main cause is the use of assisted reproductive technologies (ART). To explore the overall consequences of dual embryo transfer (DET), the literature has been reviewed systematically regarding short- and long-term outcomes of IVF/ICSI twin pregnancies i.e. pregnancy complications, maternal risks, obstetric outcome and long-term morbidity including neurological sequelae, cognitive development and family implications. Another consequence of DET is vanishing twins, which seems to be a possible cause of adverse outcome in IVF singletons. The sparse literature on vanishing twins in IVF pregnancies and the influence on the surviving co-twin were also addressed. Finally, to determine the effects of implementing elective single embryo transfer (eSET), trials concerning eSET versus DET were analysed. In the light of the steadily increasing twin birth rates and the findings in this overview, where IVF/ICSI twins carry adverse outcome, it should be emphasized that the major obstacle in IVF remains the high twin birth rate. Furthermore vanishing twins account for another hazard of DET. These problems can be resolved by implementing eSET, diminishing the twin birth rate without affecting the overall goal of achieving a healthy infant.
    Preview · Article · Aug 2005 · Human Reproduction Update
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    • "Grether and Nelson's landmark studies found no different risk in same sex versus different sex twins [Grether et al., 1993; Nelson and Ellenberg, 1995]. However, Minakami and others compared twins conceived after ovarian induction (with or without assisted reproductive techniques) with spontaneously conceived twins [Minakami et al., 1998]. Only 2.2% of the twins conceived after ovarian induction were monochorionic, whereas 57% of the spontaneously conceived twins were monochorionic. "
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    ABSTRACT: In recent years there have been a number of advances in understanding of predisposing and protective factors in the development of cerebral palsy in infants. Multiple gestation births, maternal infection, and maternal and fetal thrombophilic conditions all predispose to the development of CP in the infant. Opportunities for prevention of CP may develop from an improved understanding of these factors and their mechanisms of operation. Similar progress has been made in the evaluation of treatments for CP and the effects of these treatments on the individual's impairment, function, and disability. Selective posterior rhizotomy and Botulinum toxin A are now widely used in the treatment of spasticity. The challenge remains to determine how effectively these promising interventions can alter long-term function and quality of life outcomes in children and adults with CP.
    Full-text · Article · Feb 2001 · Mental Retardation and Developmental Disabilities Research Reviews
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    • "Furthermore, an adverse outcome of monochorionic twins at 1 year of age was associated with greater birth weight and haemoglobin discordance due to polycythaemia or anaemia in the smaller twin (Wenstro Èm et al., 1992; Honma et al., 1999). Twins conceived after ovulation induction with or without IVF did not have an increased risk of an adverse outcome compared with naturally occurring twins (Bernasko et al., 1997; Minakami et al., 1998). "
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    ABSTRACT: Monozygotic twinning is a relatively rare event in in-vivo conception, being estimated to occur in 0.42% of all births. The underlying mechanism for monozygotic twin formation is the division of the embryo early in its development. Separation of cells may theoretically occur before or after inner cell mass formation. In this analysis we report 11 cases of monozygotic twins resulting from IVF or intracytoplasmic sperm injection (ICSI) treatment cycles performed between 1991 and 1998 at St James's University Hospital, Leeds, and Bourn Hall Clinic, Cambridge, UK. Six cases (55%) followed treatment with ICSI and seven cases (64%) were in women aged > or = 35 years. This article also reviews the scientific literature discussing information pertaining to frequency, aetiology and potential complications of the monozygotic twinning phenomenon. We conclude that patients at risk of monozygotic twinning are those aged >35 years of age and those who had artificial opening in the zona pellucida by application of micromanipulation techniques. Women undergoing assisted conception treatment, particularly those with these two risk factors, must be informed of the low but definite risk of monozygotic twinning when counselled regarding the number of embryos to be transferred and chances of multiple births.
    Full-text · Article · Jan 2000 · Human Reproduction Update
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