Grech Victor
Department of Pediatrics, Mater Dei Hospital, Malta
J Turk Ger Gynecol Assoc. 2023 Mar 15;24(1):1-4. doi: 10.4274/jtgga.galenos.2022.2022-8-14.
The sex ratio at birth, defined as males/total (M/T) approximates 0.515 but is affected by many factors. Acute and chronic stress have been shown to lower M/T, and both regional and racial differences exist. This study analysed regional differences in M/T in Mexico.
Live births by sex and year were available for 1994-2020. Regional births were available for 2010-2020 for five regions: North, Centre, West, East and South.
There were 68,423,415 births for 1994-2020 and 25,436,687 for 2010-2020 (M/T=0.5060, 95% confidence interval: 0.5058-0.5062). M/T was <0.515 (p<0.0001). Live births correlated negatively with year (p<0.0001). M/T fell for 1994-2003 then rose to 2020 (p<0.0001). M/T was highest in North followed by West, South, Centre and East (p<0.0001).
Chronic stress with socioeconomic deprivation may reduce M/T and may explain the low M/T found in this study from Mexico.
出生性别比定义为男性/总数（M/T），约为0.515，但受多种因素影响。急性和慢性应激已被证明会降低M/T，且存在地区和种族差异。本研究分析了墨西哥M/T的地区差异。
可获取1994 - 2020年按性别和年份划分的活产数据。2010 - 2020年五个地区（北部、中部、西部、东部和南部）的地区出生数据也可获取。
1994 - 2020年有68,423,415例出生，2010 - 2020年有25,436,687例出生（M/T = 0.5060，95%置信区间：0.5058 - 0.5062）。M/T < 0.515（p < 0.0001）。活产数与年份呈负相关（p < 0.0001）。1994 - 2003年M/T下降，然后上升至2020年（p < 0.0001）。M/T在北部最高，其次是西部、南部、中部和东部（p < 0.0001）。
社会经济剥夺导致的慢性应激可能会降低M/T，这可能解释了本研究中墨西哥M/T较低的现象。
