Lynch Courtney D, Jackson Leila W, Buck Louis Germaine M
Epidemiology Branch, Division of Epidemiology Statistics and Prevention Research, National Institute of Child Health and Human Development, NIH, Department of Health and Human Services, Rockville, MD 20852, USA.
Paediatr Perinat Epidemiol. 2006 Nov;20 Suppl 1:3-12. doi: 10.1111/j.1365-3016.2006.00765.x.
Conception, as defined by the fertilisation of an ovum by a sperm, marks the beginning of human development. Currently, a biomarker of conception is not available; as conception occurs shortly after ovulation, the latter can be used as a proxy for the time of conception. In the absence of serial ultrasound examinations, ovulation cannot be readily visualised leaving researchers to rely on proxy measures of ovulation that are subject to error. The most commonly used proxy measures include: charting basal body temperature, monitoring cervical mucus, and measuring urinary metabolites of oestradiol and luteinising hormone. Establishing the timing of the ovulation and the fertile window has practical utility in that it will assist couples in appropriately timing intercourse to achieve or avoid pregnancy. Identifying the likely day of conception is clinically relevant because it has the potential to facilitate more accurate pregnancy dating, thereby reducing the iatrogenic risks associated with uncertain gestation. Using data from prospective studies of couples attempting to conceive, several researchers have developed models for estimating the day-specific probabilities of conception. Elucidating these will allow researchers to more accurately estimate the day of conception, thus spawning research initiatives that will expand our current limited knowledge about the effect of exposures at critical periconceptional windows. While basal body temperature charting and cervical mucus monitoring have been used with success in field-based studies for many years, recent advances in science and technology have made it possible for women to get instant feedback regarding their daily fertility status by monitoring urinary metabolites of reproductive hormones in the privacy of their own homes. Not only are innovations such as luteinising hormone test kits and digital fertility monitors likely to increase study compliance and participation rates, they provide valuable prospective data that can be used in epidemiological research. Although we have made great strides in estimating the timing and length of the fertile window, more work is needed to elucidate the day-specific probabilities of conception using proxy measures of ovulation that are inherently subject to error. Modelling approaches that incorporate the use of multiple markers of ovulation offer great promise to fill these important data gaps.
受孕定义为卵子与精子受精，标志着人类发育的开始。目前，尚无受孕的生物标志物；由于受孕发生在排卵后不久，后者可作为受孕时间的替代指标。在没有连续超声检查的情况下，排卵不易被观察到，这使得研究人员只能依赖易出错的排卵替代指标。最常用的替代指标包括：记录基础体温、监测宫颈黏液以及测量雌二醇和促黄体生成素的尿液代谢物。确定排卵时间和易孕期具有实际用途，因为它将帮助夫妇合理安排性交时间以实现或避免怀孕。确定可能的受孕日期具有临床意义，因为它有可能促进更准确的孕周计算，从而降低与妊娠不确定相关的医源性风险。利用试图受孕夫妇的前瞻性研究数据，一些研究人员开发了用于估计特定日期受孕概率的模型。阐明这些模型将使研究人员能够更准确地估计受孕日期，从而催生研究计划，扩大我们目前对关键受孕窗口期暴露影响的有限认识。虽然基础体温记录和宫颈黏液监测在多年的实地研究中取得了成功，但科学技术的最新进展使女性能够通过在家中私密地监测生殖激素的尿液代谢物，即时获得关于自身每日生育状态的反馈。诸如促黄体生成素检测试剂盒和数字生育监测器等创新不仅可能提高研究的依从性和参与率，还能提供可用于流行病学研究的宝贵前瞻性数据。尽管我们在估计易孕期的时间和长度方面取得了很大进展，但仍需要做更多工作来利用本质上易出错的排卵替代指标阐明特定日期的受孕概率。结合使用多种排卵标志物的建模方法有望填补这些重要的数据空白。
