Bhettay E, Nelson M M, Beighton P
Lancet. 1975 Oct 18;2(7938):741-3. doi: 10.1016/s0140-6736(75)90725-4.
Eleven sets of conjoined twins have been born in Southern Africa in a period of just over twelve months. Analysis of the circumstance pertaining to the conception and delivery of these children revealed considerable ethnic, geographic, and socioeconomic differences. It is possible that a ubiquitous environmental agent is a precipitating factor in this situation.
在短短十二个多月的时间里，南非有11对连体双胞胎出生。对这些孩子受孕和分娩情况的分析显示，在种族、地理和社会经济方面存在很大差异。在这种情况下，一种普遍存在的环境因素有可能是一个诱发因素。
