Related Experiment Video
Updated: Aug 5, 2026
09:04
Guide Wire Assisted Catheterization and Colored Dye Injection for Vascular Mapping of Monochorionic Twin Placentas
Published on: September 5, 2011
Congenital malformations in twins: an international study
P Mastroiacovo1, E E Castilla, C Arpino
1Birth Defects Unit, Catholic University, International Centre for Birth Defects, Rome, Italy. mc8682@mclink.it
American Journal of Medical Genetics
|April 6, 1999
Summary
Twins exhibit a higher incidence of congenital malformations compared to singletons across all anatomical sites. This comprehensive analysis confirms known associations and identifies new malformations linked to twin births.
Area of Science:
- Perinatology
- Epidemiology
- Medical Genetics
Background:
- Congenital malformations represent a significant public health concern.
- Understanding the risk factors, such as twinning, is crucial for early detection and intervention.
- Previous studies suggested a potential increase in malformations among twins, but data were limited.
Purpose of the Study:
- To investigate the association between twinning and congenital malformations.
- To compare malformation rates in twins versus singletons using a large, multi-registry dataset.
- To identify specific types of malformations more prevalent in twins.
Main Methods:
- Analysis of data from nine registries in European and Latin American countries.
- Coding of congenital malformations using the International Classification of Diseases (ICD-9).
- Calculation of malformation rates and rate ratios (RR) for twins versus singletons, with homogeneity testing (Breslow and Day test).
Main Results:
- Data included 260,865 twins and 5,572 reported malformations across 101 types.
- Homogeneous rate ratios were found for 91.1% of malformations.
- Thirty-nine malformations were significantly more common in twins than singletons, confirming known associations and identifying new ones.
Conclusions:
- Twins have a significantly higher risk of congenital malformations compared to singletons.
- This excess risk affects all anatomical sites.
- The study identified a greater number of specific malformations associated with twins than previously reported.
More Related Videos
09:52Accurate and Simple Evaluation of Vascular Anastomoses in Monochorionic Placenta using Colored Dye
Published on: September 5, 2011
09:51Model Surgical Training: Skills Acquisition in Fetoscopic Laser Photocoagulation of Monochorionic Diamniotic Twin Placenta Using Realistic Simulators
Published on: March 21, 2018
Related Concept Videos
01:49Meiosis I
Meiosis is a carefully orchestrated set of cell divisions, the goal of which—in humans—is to produce haploid sperm or eggs, each containing half the number of chromosomes present in somatic cells elsewhere in the body. Meiosis I is the first such division, and involves several key steps, among them: condensation of replicated chromosomes in diploid cells; the pairing of homologous chromosomes and their exchange of information; and finally, the separation of homologous chromosomes by a...
01:29Nondisjunction
During meiosis, chromosomes occasionally separate improperly. This occurs due to failure of homologous chromosome separation during meiosis I or failed sister chromatid separation during meiosis II. In some species, notably plants, nondisjunction can result in an organism with an entire additional set of chromosomes, which is called polyploidy. In humans, nondisjunction can occur during male or female gametogenesis and the resulting gametes possess one too many or one too few chromosomes.
02:30Genomic Imprinting and Inheritance
Diploid organisms inherit genetic material through chromosomes from both parents. Copies of the same gene are known as alleles. In most cases, both alleles are simultaneously expressed and allow various cellular processes to function optimally. If one of the alleles is missing or mutated, the expression of the other allele can compensate; however, this is not true for all genes.
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...
The expression of some genes depends on which parent passed the gene to the offspring, through a phenomenon known as...
01:43Sex Linked Disorders
Like autosomes, sex chromosomes contain a variety of genes necessary for normal body function. When a mutation in one of these genes results in biological deficits, the disorder is considered sex-linked.
01:21Nondisjunction
Nondisjunction is the failure of homologous chromosomes or sister chromatids to separate correctly and move to the opposite poles of the cells. This produces daughter cells with abnormal chromosome numbers. Nondisjunction is common during anaphase I or anaphase II of meiosis. Mutations in synaptonemal complex proteins that attach homologous chromosomes increase the chances of nondisjunction in anaphase I of meiosis I. In contrast, mutations in topoisomerases and condensins that hold sister...
01:07Teratogenicity
The ability of a drug to produce structural deformations and functional abnormalities in the developing embryo or the fetus is called teratogenicity, and the drug producing this effect is known as a teratogen. Teratogenic effects include stillbirth, miscarriage, intrauterine growth restriction, and neurocognitive delay. A teratogen may affect the embryo at different stages of development, which is important in determining the type and extent of the damage. During blastocyst formation, the early...