Kirchengast S, Huber J
Institute for Anthropology, University of Vienna, Althanstrasse 14, A-1090, Vienna, Austria.
Hum Nat. 2001 Jun;12(2):123-40. doi: 10.1007/s12110-001-1020-z.
The present study analyzes body fat distribution, a well-known and important indicator of reproductive capability, in young women between 18 and 28 years of age (mean=23.3 years) suffering from secondary amenorrhea and therefore temporary infertility resulting from self-starvation. Body composition parameters estimated by means of dual energy x-ray absorptiometry and the fat distribution index, indicating body shape, were compared with those of healthy controls. Although members of the infertile, amenorrheic group exhibited dramatically low body weight and total amount of body fat, and therefore a marked negative energy balance in comparison with the healthy controls, the sex-specific fat distribution patterns did not differ between infertile and fertile young women. In contrast, the lower the weight and total fat amount, the more gynoid the fat distribution, even in infertile women. This observation may be interpreted in an evolutionary sense: Our ancestors had to cope with frequent food shortages, even starvation, and therefore lengthy periods of negative energy balance. In addition to pregnancy and lactation, temporary infertility as a result of long-term negative energy balance was not an uncommon phenomenon in female life histories. Nevertheless, after a time of plenty, reproductive function recovered, and therefore the gynoid fat distribution patterns in temporarily infertile young women may be interpreted as signal of reproductive capability, which resumes after a time of surplus.
本研究分析了18至28岁(平均23.3岁)因自我饥饿导致继发性闭经从而暂时不孕的年轻女性的体脂分布情况,体脂分布是生殖能力一个广为人知且重要的指标。通过双能X线吸收法估算的身体成分参数以及表明身体形状的脂肪分布指数,与健康对照组进行了比较。尽管不孕且闭经组的女性体重和体脂总量极低,与健康对照组相比存在明显的负能量平衡,但不孕和可育年轻女性之间特定性别的脂肪分布模式并无差异。相反,体重和总脂肪量越低,脂肪分布越呈梨形,即使在不孕女性中也是如此。这一观察结果可以从进化的角度来解释:我们的祖先不得不应对频繁的食物短缺,甚至饥饿,从而经历长时间的负能量平衡。除了怀孕和哺乳,长期负能量平衡导致的暂时不孕在女性的生命历程中并非罕见现象。然而,在食物充足一段时间后,生殖功能会恢复,因此暂时不孕的年轻女性的梨形脂肪分布模式可被视为生殖能力的信号,在食物过剩一段时间后生殖能力会恢复。