TABLE 1.

TABLE 1. Changes in the Absolute Numbers and Ratio of Twin Births, USA, 1973 and 1992

						All Others
All Races			White			Total				Black
	No. of	No. of		No. of	No. of		No. of	No. of		No. of	No. of
	Twin	Total		Twin	Total		Twin	Total		Twin	Total
Year	Births	Births	Ratio	Births	Births	Ratio	Births	Births	Ratio	Births	Births	Ratio
1992	95,372	4,065,014	23.5	72,000	3,131,679	23.0	23,372	933,355	25.0	19,634	719,396	27.3
1973	56,772	3,136,695	18.1	44,452	2,551,030	17.4	12,325	585,935	21.0	11,201	512,597	21.9

(Adapted from Taffel SM: Demographic trends in twin births: USA. In Keith LG, Papiernik E, Keith DM, Luke B [eds]: Multiple Pregnancy: Epidemiology, Gestation and Perinatal Outcome. London, Parthenon Publishing Group, 1995)