Is there increased monozygotic twinning after assisted reproductive technology?
1Reproductive Services, Melbourne IVF, The Royal Women's Hospital, Melbourne, Australia. manuela.toledo@mivf.com.au
The Australian & New Zealand Journal of Obstetrics & Gynaecology
|September 21, 2005
Summary
Assisted reproductive technologies may increase the risk of monozygotic twinning. Further research is needed to understand the causes and implications of this association for twin pregnancies.
Area of Science:
- Reproductive medicine
- Maternal-fetal medicine
- Genetics
Background:
- An observed association exists between assisted reproductive technologies (ART) and an increased incidence of monozygotic twinning over the past two decades.
- The precise mechanisms underlying ART-related monozygotic twinning remain unclear, with several theories proposed.
- Established risks associated with monozygotic twins, including increased perinatal morbidity and mortality, underscore the importance of understanding this association.
Purpose of the Study:
- To review assisted reproductive technologies potentially linked to a higher risk of monozygotic twinning.
- To highlight specific ART procedures, such as intracytoplasmic sperm injection, assisted hatching, and blastocyst transfers, that may contribute to this risk.
- To emphasize the clinical significance of determining the true incidence of monozygotic twinning following ART.
Main Methods:
- Literature review of studies investigating the link between assisted reproductive technologies and monozygotic twinning.
- Analysis of proposed mechanisms and theories for ART-induced monozygotic twinning.
- Examination of specific ART procedures and their potential association with increased monozygotic twinning rates.
Main Results:
- Several assisted reproductive technologies, including intracytoplasmic sperm injection, assisted hatching, and blastocyst transfers, are implicated in the increased risk of monozygotic twinning.
- The exact causal pathways remain incompletely understood.
- The review synthesizes current knowledge on ART-associated monozygotic twinning.
Conclusions:
- Understanding the incidence of monozygotic twinning after ART is crucial due to the known higher risks for twins.
- Further research is warranted to elucidate the causative factors and refine ART protocols to mitigate risks.
- Accurate data on monozygotic twinning rates post-ART are essential for informed clinical practice and patient counseling.
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