There is a town by the name of Igbo-Ora in southwest Nigeria which has the highest rate of twin births in the whole world.So sure are the inhabitants of this town of their unique distinction that on the road going into the town there is a large stone which bears a proud message welcoming visitors to the land of the twins.
Nigeria has a large population and it also has the world's highest twinning rate. A study conducted by British gynecologist Patrick Nylander recorded an average of 45 to 50 sets of twins per 1000 live births in the southwest of the country. That makes it a rate of almost 5% of all births compared with a rate of around 1.2% for Western Europe and 0.8% for Japan. However fertility pills have increased the incidence of twin births even in the West.
There is hardly a family in Igbo-Ora that doesn't have a set of twins. In Igbo-Ora twin births are regarded as a blessing and a gift from God.Nobody is really sure as to the reasons for it.The locals attribute it to tradition which suggests genetic reasons for the phenomenon, while others say its just plain chance.The most widely accepted theory is that it is due to diet.
An important ingredient of the Yoruba people's diet is the 'yam' or cassava, a plant with a tuber root. The root is eaten in addition to the leaves and flowers. Yams contain a natural hormone phytoestrogen which may stimulate the ovaries to produce an egg from each side, causing multiple births.But others are not so sure. They point to the fact that yams are cultivated in some regions of Asia for their contraceptive qualities.Presently there seems to be no scientific evidence that yam consumption can cause multiple births.
Meanwhile in Yorubaland the birth of twins is a good omen and they are treated with respect. There are elaborate rituals surrounding twins in Africa which vary widely from country to country.These traditions look set to continue as the real reason for the prevalence of twin births is certainly set to baffle the medical fraternity for some time to come.