Conjoined twinning in Sweden.

A small "epidemic" of conjoined twinning is reported occurring at the Skövde Central hospital in 1975-76. Three parts were observed, the annual birth number of 2300. During a ten-year period, 10 cases of conjoined twinning were reported to the Register of Congenital Malformations in Sweden, indicating a probable incidence of 1:75000 births. These 10 cases were distributed all over the country. Interviews with the three women who gave birth to the Skövde conjoined twins revealed no common factor which could be of aetiological significance.