Twin Research Reviews Research Articles

Most Unusual Twin Pairs: A Look at Uterus Didelphys / Twin Research Reviews: Prenatal Aneuploidy Screening for Twin Pregnancies; Twin Conceptions by Same-Sex Male Couples; Legal Personality of Conjoined Twins; Twin Study of Cannabis Use / Human Interest and Importance: Being Taken for Twins Saved Sisters; Twin Children of Jailed Nobel Prize Winner; British 'Biracial' Twins; Triplets Born at Start

A review of an unusual twin type-twins born to women with two uteri (uterus didelphys)-is presented. This review is followed by summaries of recent research and perspectives concerning prenatal aneuploidy screening for twin pregnancies, twin conceptions by same-sex male couples, legal personality of conjoined twins, and a twin study of cannabis use. Interesting information about twins that has appeared in the media is also presented, namely how being taken for twins saved a pair of sisters; twin children of a jailed Nobel Prize winner, British 'biracial' twins, triplets born at the start of Russia's attack on Ukraine, and twins born in different years.

Partnership with the University of São Paulo Panel of Twins: A Four-City Tour and More / Twin Research Reviews: Twin Research on Binge Eating; Twins' Physical Outcomes Linked to Different Diets; Working Conditions and Sickness Absence in Swedish Twins; Facial Morphology Differences in Monozygotic Twins / Human Interest and Importance: Michigan Family Forced to Adopt Their Own Twins; Ethics of

This article begins with an overview of twin research in Brazil, initiated by the University of São Paulo Panel of Twins. I met with many new research collaborators and students while on a fall 2023four-city lecture tour in that country. A meeting with a world-famous surgeon who recently separated craniopagus conjoined twin pairs is also described. This overview is followed by summaries of twin research on binge eating, twins' physical outcomes linked to different diets, working conditions and sickness absence in Swedish Twins and facial morphology differences in monozygotic twins. The final section of this article provides a sampling of human interest stories with important implications. They include a Michigan family forced to adopt their own twins, ethical issues surrounding the hiring of a surrogate to bear twins; twin survivors of the Israel-Hamas war, a twin pregnancy with a double uterus, and three twin pairs on the same women's soccer team.

Do Males Affect Twinning Events? A Review of Current Findings/Twin Research Reviews: Monozygotic Twins Discordant for Parkinson's Disease; Fetal Loss in Twin Pregnancies Following Prenatal Diagnosis; Uterine Rupture and Repair in an Early Twin Pregnancy; Twin Study of Affectionate Communication/Human Interest: Conjoined Twins in a Triplet Set; Identical Twin Nurses Deliver Identical Twins; Identical Twins Discordant for COVID-19 Recovery Course;

Research into the origins of twinning has focused mostly on contributions from the female side of the family. A review of current findings suggests that possible male contributions to twinning events have been overlooked. This section is followed by brief reviews of twin research concerning monozygotic twins discordant for Parkinson's disease, fetal loss in twin pregnancies following prenatal diagnosis, uterine rupture and repair in an early twin pregnancy and a twin study of affectionate communication. The concluding portion of this article presents human interest stories involving twins that are both informative and poignant, namely conjoined twins in a triplet set, identical twin nurses who delivered identical twins, identical twins discordant for COVID-19 recovery course, identical twins who passed away from COVID-19 and archeological finds of the oldest identical twins.

Remembering John C. Loehlin: 'Our Field Has Lost a Lion'/Twin Research Reviews: Cognitive Skills and Social Mobility, Risk of Arachnoid Hemorrhage, Heritability of Dental Traits, and Twin-to-Twin Transfusion Syndrome/Media Reports: Identical Twins With Different Health Histories, Twins Born 97 Days Apart, Retiring Twin Tennis Players, TikTok Twins and Twin Reality Stars.

John C. Loehlin, professor of psychology at the University of Texas, at Austin, passed away on August 9, 2020. John was 94 years of age. He will be remembered for his seminal contributions that have furthered the field of twin research in so many ways. An overview of his career is presented, with fond memories from his son and several colleagues. This tribute is followed by reviews of twin research on cognitive skills and social mobility, risk of subarachnoid hemorrhage, heritability of selected dental traits and twin-to-twin transfusion syndrome. Finally, twin-related topics of human interest include identical twins with different health histories, twins born 97 days apart, retiring twin tennis players, TikTok twins and twin reality stars.

Dizygotic Twin Infants: Controversial Case Study Series/Twin Research Reviews: Twin and Non-twin ICSI Conceptions; Emory University Twin Study; Labor in Multiple Pregnancy After Previous C-Section Delivery; Cell-Free DNA Fetal Fraction in Twin Pregnancies/News Reports: Twin Survivor of Auschwitz; Twins Trading Places; Identical Twin Foals; Twins Born in Different Decades; Twins Ambulette Service.

This article describes a 1930s case study series involving dizygotic female twin infants. The twins' development was evaluated following periods of intentionally restricted practice and minimal social stimulation. In the opinion of the author of the current article, the study is very unsettling and unacceptable, despite the lack of institutional review boards at that time. This discussion is followed by twin research reviews of recent papers concerning twin and non-twin intracytoplasmic sperm injection conceptions, the Emory University Twin Study of cardiac and brain functions, labor trials in multiple pregnancies after previous C-section delivery and cell-free DNA fetal fraction in twin pregnancies. The article concludes with news items of a twin survivor of Auschwitz, a situation in which twins traded places, the rare birth of identical twin foals, the novel delivery of co-twins in different decades and the Twins Ambulette Service.

Oliver Sacks: Our Correspondence About Twins/Twin Research: Vanishing Twins Syndrome; Discordant Sex in MZ Twins; Pregnancy Outcomes in IVF and ICSI Conceived Twins/Print and Media: Superfetated Twins; Twins Discordant for Smoking; Twins in Fashion; Yale University Twin Hockey Players; Conjoined Twin-Visiting Professor.

The late neurologist and author, Oliver Sacks, published an insightful 1986 review of Marjorie Wallace's book, The Silent Twins, in the New York Times. Taking exception to his assertion about Sir Francis Galton, I wrote a letter to the Times' editor. The letter was unpublished, but it brought a wonderful response from Sacks himself that is reproduced and examined. Next, brief reviews of twin research concerning the vanishing twin syndrome (VTS), discordant sex in a monozygotic (MZ) twin pair, and multiple pregnancy outcomes from assisted reproductive technology (ART) are presented. This section is followed by popular coverage of superfetated twins, smoking-discordant co-twins, twins in fashion, Yale University twin hockey players, and a visiting professor who was a conjoined twin.

Reared-Apart Chinese Twins: Chance Discovery/Twin-Based Research: Twin Study of Media Use; Twin Relations Over the Life Span; Breast-Feeding Opposite-Sex Twins/Print and Online Media: Twins in Fashion; Second Twin Pair Born to Tennis Star; Twin Primes; Twin Pandas.

A January 2017 reunion of 10-year-old reared-apart Chinese twin girls was captured live on ABC's morning talk show Good Morning America, and rebroadcast on their evening news program Nightline. The twins' similarities and differences, and their participation in ongoing research will be described. This story is followed by reviews of twin research concerning genetic and environmental influences on media use, twin relations across the lifespan and the breast-feeding of opposite-sex twins. Popular interest items include twins in fashion, the second twin pair born to an internationally renowned tennis star, twin primes and twin pandas.

Remembering Irving I. Gottesman: Twin Research Colleague and Friend Extraordinaire/Research Studies: Face-Lift Technique Comparison in Identical Twins; Raising Preterm Twins; Fetal Behavior in Dichorionic Twin Pregnancies; Co-Bedding and Stress Reduction in Twins/Public Interest: Identical Co-Twins' Same Day Delivery; Teaching Twins in Bosnia; Twin Auctioneers; Sister, the Play.

Dr Irving I. Gottesman, a colleague, friend, and long-time member of the International Society of Twin Studies passed away on June 29, 2016. His contributions to twin research and some personal reflections are presented to honor both the man and the memory. This tribute is followed by short reviews of twin research concerning differences between cosmetic surgical techniques, the rearing of preterm twins, behavioral observations of dichorionic fetal twins, and the outcomes of co-bedding twins with reference to stress reduction. Interesting and informative articles in the media describe identical co-twins who delivered infants on the same day, educational policies regarding twins in Bosnia and the United Kingdom, unusual practices of twin auctioneers, and a theatrical production, Sister, featuring identical twins in the leading roles.

Solvent Exposure and Parkinson's Disease: Co-Twin Control Study/ Twin Research Reports / Human Interest Stories

Naturally occurring co-twin control designs can assess associations between environmental hazards and disease risk because the genotypes of monozygous twins are the same. The first population-based study to explore links between solvent exposure and Parkinson's disease used 49 discordant monozygous twin pairs, as well as a comparison group of 50 discordant dizygous twin pairs. The methods, findings and implications from this important study are reviewed. Reviews of twin research concerning gender identity disorder, prenatal development and the VATER syndrome follow. A sampling of engaging and informative twin-related news items is also presented.

Twins' Injuries: Genetic and Environmental Risks / Twin Research Reports / Human Interest Stories

The relative contributions of genetic and environmental factors to unintentional injuries are of interest to families with young twins. A recent study found that childhood injuries are explained mostly by child-specific environmental factors. Next, twin research reviews of the association between periodontal disease and cancer, secular trends in gestational age and birthweight, and language development in hearing and deaf co-twins are also summarized. Interesting reports of newborn twins, twin-like relationships, twin interactions and missed twin relationships are presented.

A Pair of Meetings: Twins (UCLA Center for Society and Genetics) and the 13th International Society for Twin Studies Congress (ISTS, Seoul, South Korea) / Twin Research Reviews: Female Sexuality; Maternal Age and Multiple Pregnancy Success / In the News: In Separate Wombs; Big Twinning Rates in Small Towns; School Enrollment Policy Hurts Twins; Establishing Paternity of Twins; Stars Are

The key aspects and features of the May 2010 twin panel 'Everything you wanted to know about twins', hosted by UCLA Center for Society and Genetics on May 18, 2010 are discussed. Other issues and topics raised by the panel are highlighted.

Population-Based Research: Breastfeeding Multiple Birth Infants / Twin Research Reviews and News: Perceived Aging in Twins; Separation of Conjoined Twins; School Placement Legislation / Twins in Education, Fashion and Humanitarian Events

The health benefits of breastfeeding are well known. However, less is known about the frequency and duration of breastfeeding in twins. A population-based study of maternal factors associated with the early cessation of breastfeeding in preterm and term twins is reviewed. This is followed by research reviews and news concerning aging in twins, conjoined twin separation and school legislation for multiple birth children. Twins and quadruplets who have distinguished themselves in the areas of education, fashion design and humanitarian efforts are highlighted.

Twin Loss: The Annual Convention / Twin Research Reviews: Childhood Empathy; Hormone Replacement Therapy and Skeletal Muscle; Multiple Birth Conception in Older Women / Twins in the Media: Twins With Kidney Disease; A Pair of Poets; The Other Twins in the Metrodome

Loss of a twin has been largely overlooked by bereavement counselors and clinicians. This particular type of loss is also poorly understood among the public. Consequently, some bereaved twins have established a unique organization, Twinless Twins Support Group International, for the purpose of sharing this traumatic life experience with one another. The present article reviews events from the annual convention of Twinless Twins, held in July 2009, in Denver, Colorado. Selected findings from research on twin loss are also presented. Next, twin research concerned with the origins and implications of empathy, hormone replacement therapy and multiple birth conception will be reviewed. This article concludes with summaries of real life stories of twins' kidney disease, literary talent and retirement festivities.

Monozygotic Triplets: Concordance and Discordance for Cleft Lip and Palate / Twin Research Reviews: Depression in Mothers of Multiples; Depression in Mothers and Fathers of ART Conceived Multiples; Epigenetic Differences in Monozygotic Twins; Congenital Anomalies in Surviving Twins / Headlines × Two: Twin Chefs; The World's Largest Twin Registry; Twin Table Tennis Champions

A review of twin research on cleft lip and palate is presented. This information is accompanied by a look at the lives of young monozygotic (MZ) male triplets concordant for cleft lip, but discordant for the type and placement of the cleft and for the presence of cleft palate. Research on depression in mothers and fathers of twins conceived naturally and by artificial reproductive techniques follows. Current findings and implications of epigenetic differences in MZ twins are also summarized. Interesting life history events surrounding MZ twin chefs and table tennis players, as well as plans to construct the world's largest twin registry, are presented in the final section.

Twins Reared Apart: A Forgotten Case / Twin Research Reviews: X-Inactivation and Female Co-Twin Discordance for Hemophilia; Transplantation for Breast Reconstruction; Chimerism and Telomere Attrition in Dizygotic Twins; Divergent Life Histories in Twins Reared Apart / Current Concerns: High ACT-Scoring Twins; Dating a Twin; When Gender Identities Diverge / The Holland Twins

A forgotten story of monozygotic twins reared apart is described. The pair, born in 1941 in Fribourg, Switzerland, were separated due to switch-baby incident in the hospital. This caused one twin to be raised as a singleton by an unrelated family, and the other twin to be raised as a 'dizygotic' twin with an unrelated child. This is followed by reviews of recent twin research and case studies of X-inactivation and hemophilia, breast reconstruction, chimerism and life histories. The final section of the article includes human interest pieces on academic twins, dating twins, transsexual twins and athletic twins.

Twins and Politics: Political Careers and Political Attitudes / Twin Research Reviews: Pair-Bonding; Facial Expressivity in Reared Apart Twins; Educating Multiples / Stories That Move and Amaze Us: A Military Funeral; A Twins' Reunion; Egyptian Septuplets; Rare Occupations

Twins and twin research are providing fresh insights into the roots of political behavior. This topic is approached from dual perspectives: why some individuals choose to become politicians, and why individuals vary in their political attitudes and interests. Reviews of timely twin studies in the areas of pair-bonding, facial expressivity and education follow. Finally, some extraordinary events in the lives of twins and their families are revealed.

Co-Twin Controls: Facioplasty / Twin Research Reviews: Congenital Anomalies; Personality and Coital Orgasmic Infrequency; Physical Activity Participation / Newsworthy: Twins, Triplets and Quads; School Legislation Update; Premature Twins in Court

Abstract The usefulness of monozygotic (MZ) twins for studying the efficacy of different face lift techniques is described. The data suggest that no particular procedure out of four under consideration is superior to any other. Next, reviews of recent twin studies of congenital anomalies, personality traits and coital orgasmic infrequency, and physical activity participation are presented. Finally, timely topics of public interest are also described. They include a rare birth consequence of artificial reproductive technology, an update on state legislation regarding parents' rights to decide the classroom placement of their young twins, and medical malpractice lawsuits involving premature twins.

Elizabeth M. Bryan: Tributes From Home and Abroad; Research Reviews: Anorexia Nervosa in Opposite-Sex Twins, Twin Study of Self-Esteem, DNA Differences in Monozygotic Twins; Twins and More Twins: Twins Living Apart, Twins Playing Together, Twins Working Together, Twins Playing Apart, Multiple Birth Odds

Elizabeth M. Bryan: Tributes From Home and Abroad May 13, 1942 - February 21, 2008 The life and work of Dr Elizabeth M. Bryan, our late distinguished twin studies colleague, are remembered. Tributes come from colleagues in the United States and the United Kingdom, where Elizabeth lived and worked. This section is followed by reviews of twin research on anorexia nervosa, self-esteem and DNA differences in monozygotic twins. The lives of some noteworthy twins are also briefly chronicled, both for their scientific value and human interest. An update on current twinning rates follows.