AGE AT MENARCHE AT SEA-LEVEL AND HIGH-ALTITUDE IN PERUVIAN WOMEN OF DIFFERENT ETHNIC-BACKGROUND

The objective of the present study was determine recalled age at menar che in women of Quechua and non-Quechua ancestry living in the cities of Lima (altitude 150 m), Cusco (altitude 3,400 m), and Cerro de Pasco (altitude 4,340 m), Peru. The sample included 296 Mestizo urban women , 20-30 years, who were natives of Lima (n = 72), Cusco (n = 81), and Cerro de Pasco (n = 143). Ethnic composition was determined by two par ental surnames, and women were classified as Quechua when one or both surnames were of Quechua origin and non-Quechua when both surnames wer e of Spanish origin. Age at menarche was obtained by recall to nearest year. In Quechua as in non-Quechua women, age at menarche occurred la ter as residence altitude increased. Mean ages at menarche for the com bined Quechua and non-Quechua samples were 13.1 +/- 1.4 years in Lima, 13.9 +/- 1.9 years in Cusco, and 14.6 +/- 1.69 years in Cerro de Pasc o. Thus age at menarche occurs later at high altitude independent of e thnic influence. (C) 1994 Wiley-Liss, Inc.