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The incidence of twinning in India, as estimated on the basis of data from the various types of maternity centers, so as to include both urban and rural population, appears to be 15.97 per thousand (12.6 DZ, 3.3 MZ). The incidence is significantly higher in rural than urban populations (18.1 vs. 11.8 per thousand). It is suggested that this may be accompanied with a higher production of DZ, possibly opposite-sexed twins.
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Goswami et al. (1975) studied this question.
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