Hakim R B, Gray R H, Zacur H
Department of Population Dynamics, Johns Hopkins University School of Hygiene and Public Health, Baltimore, Maryland, USA.
Am J Obstet Gynecol. 1995 May;172(5):1510-7. doi: 10.1016/0002-9378(95)90489-1.
We describe the epidemiologic characteristics of conception, including subclinical early pregnancy loss, in a population of healthy women volunteers who had heterogeneous fertility experiences, and we describe the conception experience of women within this group who had evidence of impaired fertility.
This was a prospective observational study of a cohort of women employed in two semiconductor manufacturing facilities. A total of 148 volunteers completed interviews and daily diaries and collected daily urine specimens for an average of 7 months. Conception, including subclinical losses and clinical pregnancies, was determined with a highly sensitive and specific assay for urinary human chorionic gonadotropin, and ovulation was determined with assays of urinary ovarian steroid hormones.
There were 679 menstrual cycles at risk for pregnancy contributed by 124 (84%) of the 148 women. Women with evidence of subfertility before or during the study period had a rate of early pregnancy loss of 70% compared with 21% in women without fertility problems (relative risk 2.6, 95% confidence interval 1.8 to 3.8). The risk of pregnancy loss associated with subfertility increased with age and remained the same in women treated with clomiphene citrate.
These results suggest that subfertile women have increased subclinical pregnancy losses regardless of fertility treatment and that the association between reduced fertility and advancing age may be related, in part, to early subclinical pregnancy loss.
我们描述了一群生育经历各异的健康女性志愿者受孕的流行病学特征，包括亚临床早期妊娠丢失情况，并描述了该组中存在生育能力受损证据的女性的受孕经历。
这是一项对在两家半导体制造工厂工作的女性队列进行的前瞻性观察研究。共有148名志愿者完成了访谈和每日日记，并平均7个月收集每日尿液样本。通过对尿人绒毛膜促性腺激素的高灵敏度和特异性检测来确定受孕情况，包括亚临床丢失和临床妊娠，并通过检测尿卵巢甾体激素来确定排卵情况。
148名女性中的124名（84%）贡献了679个有妊娠风险的月经周期。在研究期间之前或期间有生育力低下证据的女性，早期妊娠丢失率为70%，而无生育问题的女性为21%（相对风险2.6，95%置信区间1.8至3.8）。与生育力低下相关的妊娠丢失风险随年龄增加，且接受枸橼酸氯米芬治疗的女性风险保持不变。
这些结果表明，无论是否接受生育治疗，生育力低下的女性亚临床妊娠丢失都会增加，而且生育力降低与年龄增长之间的关联可能部分与早期亚临床妊娠丢失有关。
