Unborn twins interact with each other as early as 14 weeks
PADOVA, Italy, January 12, 2011 (LifeSiteNews.com) - Unborn twin babies socialize as early as week 14 of gestation, a new study has shown.
Italian researcher Dr. Umberto Castiello of the University of Padova and associates used an advanced method of ultrasonography, which enables the movements of the babies to be recorded over time in 3D, to study five pairs of twins from a sample of low-risk pregnant women attending the Institute of Child Health I.R.C.C.S. Burlo Garofolo.
The purpose of the study was to see how twins interacted with each other in their mothers’ wombs and to determine if the interaction was intentional or accidental.
“Newborns come into the world wired to socially interact,” Dr. Castiello states in the preamble to the study report, then poses the question, “Is a propensity to socially oriented action already present before birth?”
Twin pregnancies provided the research team with a unique opportunity to investigate the social pre-wiring hypothesis.
“Unlike ordinary siblings, twins share a most important environment – the uterus. If a predisposition towards social interaction is present before birth, one may expect twin foetuses to engage in some form of interaction,” the researchers say.
“Although various types of inter-twins contact have been demonstrated starting from the 11th week of gestation,” Dr. Castiello said, “no study has so far investigated the critical question whether intra-pair contact is the result of motor planning rather then the accidental outcome of spatial proximity.”
The five pairs of twins were studied during two separate recording sessions carried out at the 14th and 18th week of gestation.
The first 20-minute recording sessions showed the unborn twins touching each other as well as themselves, and the uterine wall.
During the second recording, four weeks later, their interest in their twin was approximately three times higher, with almost 30 per cent of movements directed towards the sibling. Those movements were also more accurate and of longer duration then self-directed ones, the researchers reported.
“We demonstrate that by the 14th week of gestation twin foetuses do not only display movements directed towards the uterine wall and self-directed movements, but also movements specifically aimed at the co-twin, the proportion of which increases between the 14th and 18th gestational week,” the scientists stated.
The proportional increase in contact with the twin was reported to be consistent among the ten babies studied.
The researchers conclude that performance of movements towards the co-twin is not accidental.
“Starting from the 14th week of gestation twin foetuses plan and execute movements specifically aimed at the co-twin,” the authors wrote, stating that “when the context enables it, as in the case of twin foetuses, other-directed actions are not only possible but predominant over self-directed actions.” The findings provided quantitative empirical evidence that unborn babies are very much aware of their surroundings and of the presence of a twin with them in their mother’s womb, said the researchers.
The full text of the study, titled “Wired to Be Social: The Ontogeny of Human Interaction” is available here.