Igbo-Ora, the scientific enigma of the twin capital of the world'

"Back in the 1970s and 1980s, British gynecologist Patrick Nylander documented rates of between 45 and 50 twin births per 1,000 live births in Igbo-Ora, well above the global average. Decades later, new academic research has confirmed that the incidence remains extraordinary. A study by the University of Lagos and the University of Benin, published in the U.S.-based National Journal of Medicine, again placed the local rate above the global average."

"While globally there are around 12 twin births per 1,000 deliveries, according to a 2021 study published in the journal Human Reproduction, the proportion in this city in southwestern Nigeria is much higher. A stroll through its streets, in this territory of nearly 200,000 inhabitants, reveals an unusual presence of identical twins walking, shopping, or playing in the squares."

"However, despite decades of scientific study, there is no definitive explanation. Hypotheses range from genetic factors and inbreeding patterns to environmental conditions and dietary elements. By the 1970s, Nigeria was already recognized by the scientific community as having one of the highest twin rates in the world."

Igbo-Ora, a Nigerian city of nearly 200,000 inhabitants located 60 miles from Lagos, is renowned as the world's twin capital due to its exceptionally high rate of twin births. While the global average stands at approximately 12 twin births per 1,000 deliveries, British gynecologist Patrick Nylander documented rates between 45 and 50 per 1,000 live births in the 1970s and 1980s. Recent studies by the University of Lagos and University of Benin confirm these elevated rates persist today. The city celebrates the World Twins Festival annually on October 11 since 2018, attracting locals and international visitors. Despite extensive scientific research spanning decades, the precise cause remains unexplained, with hypotheses including genetic factors, inbreeding patterns, environmental conditions, and dietary elements. Similar phenomena exist in Kodinhi, India and Candido Godoi, Brazil, but neither matches Igbo-Ora's documented rates.

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