Undernutrition may affect fecundability, but few studies have quantified this relationship. In rural Bangladesh, where newlywed couples face strong pressures to become pregnant, we assessed fecundability, estimated by time to pregnancy (TTP), and its association with preconceptional thinness among nulligravid, newlywed female adolescents. During 2001-2002, 5,516 newlywed women aged 12-19 years participated in a home-based, 5-weekly surveillance system for 5-6 years to enrol pregnant women into an antenatal vitamin A or β-carotene supplementation trial. Thinness was defined as a left mid-upper arm circumference (MUAC) ≤21.5 versus >21.5 cm. At each visit, staff obtained a monthly history of menstruation. Report of amenorrhea prompted a human chorionic gonadotropin urine test to confirm pregnancy. We derived hazard ratios (with 95% confidence intervals [CI]) for pregnancy and Kaplan-Meier curves for TTP. Ages of women at marriage and pregnancy detection (mean ± standard deviation) were 15.3 ± 1.9 and 17.0 ± 1.9 years, respectively. A total of 82.7% of thinner and 87.3% of better nourished women became pregnant. The unadjusted and multivariable relative hazard of ever becoming pregnant was 0.84 (95% CI [0.78, 0.89]) and 0.86 (95% CI [0.81, 0.92]), respectively, and TTP was 12 weeks longer (median [95% CI]: 63 [58-68] vs. 51 [49-54]) in women whose MUAC was ≤21.5 versus >21.5 cm. In rural Bangladesh, thin adolescent newlywed girls have a lower probability of becoming pregnant and experience a longer time to pregnancy.

中文翻译：

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瘦弱和生育能力：孟加拉国农村青少年结婚后的怀孕时间。

营养不良可能会影响生育能力，但很少有研究量化这种关系。在孟加拉国农村地区，新婚夫妇面临着巨大的怀孕压力，我们评估了未怀孕的新婚女性青少年的生育能力（通过怀孕时间（TTP）估计）及其与孕前瘦弱的关系。2001-2002年期间，5,516名12-19岁的新婚妇女参加了为期5-6年、每周5次的家庭监测系统，让孕妇参加产前维生素A或β-胡萝卜素补充试验。瘦度定义为左中上臂周长 (MUAC) ≤ 21.5 与 > 21.5 厘米。每次访问时，工作人员都会获取每月的月经史。闭经的报告促使进行人绒毛膜促性腺激素尿检以确认怀孕。我们得出了妊娠风险比（95% 置信区间 [CI]）和 TTP 的 Kaplan-Meier 曲线。女性结婚年龄和怀孕年龄（平均值±标准差）分别为15.3±1.9岁和17.0±1.9岁。总共有 82.7% 的较瘦女性和 87.3% 的营养较好女性怀孕了。怀孕的未调整和多变量相对风险分别为 0.84 (95% CI [0.78, 0.89]) 和 0.86 (95% CI [0.81, 0.92])，TTP 延长 12 周（中位数 [95% CI]） ： MUAC ≤ 21.5 厘米与 > 21.5 厘米的女性分别为 63 [58-68] 和 51 [49-54]）。在孟加拉国农村地区，瘦弱的青春期新婚女孩怀孕的可能性较低，并且怀孕时间较长。