Nelson M M, Bhettay E, Beighton P
S Afr Med J. 1976 Apr 24;50(18):697-8.
Twelve sets of conjoined twins have been born in Southern Africa since February 1974. This possibly represents a significant increase in the incidence of Siamese twinning and may be the result of unknown environmental agents. Several of the sets of twins were diagnosed antenatally. In view of the current circumstances a high index of suspicion is probably justified in the presence of maternal hydramnios or fetal malpresentation.
自1974年2月以来，南非已出生了12对连体双胞胎。这可能意味着暹罗双胞胎的发病率显著上升，可能是由未知环境因素导致的。其中几对双胞胎在产前被诊断出来。鉴于目前的情况，当出现母亲羊水过多或胎儿胎位不正时，高度怀疑可能是合理的。
