Superfétation — Wikipedia

The superfection is the implementation of a new pregnancy in a uterus which already contains a developing pregnancy ^{[ first ] , [ 2 ]} . Extremely rare in humans ^{[ 2 ] , [ 3 ] , [ 4 ]} , a dozen cases have been publicized ^{[ 5 ]} : L’A in Arkansas in 2009 ^{[ 6 ]} , one in Australia in 2015 ^{[ 7 ]} , one in California in 2016 ^{[ 8 ]} , one in Uganda in 2020 ^{[ 9 ]} or two in England in 2021 ^{[ ten ] , [ 11 ]} .

This phenomenon is a little more common in other species of mammals. This is the case, for example, of the brown hare or European hare (Rabbit europseus) , which allows a female to produce 5 worms per year, in just 6 months, while her gestation is 41 days. His successive gestations “overlap” therefore, which reduces the average duration between the ranges to 37-38 days. This increases its reproductive chances of success by more than 30% in each period ^{[ twelfth ]} [See the “Behavior and Reproduction” section of the article devoted to this hare].

Émile Littré attributes the treaty Of the superfection To the naturalist doctor Léophanès ^{[ 13 ] , [ 14 ]} . This superfection phenomenon, now proven by medical imaging (high resolution ultrasound), was therefore already suspected before Aristotle ^{[ twelfth ]} .