Zinaman M J, Clegg E D, Brown C C, O'Connor J, Selevan S G
Georgetown University Medical Center, Washington, D.C., USA.
Fertil Steril. 1996 Mar;65(3):503-9.
To examine the fertility and pregnancy wastage rates in a group of presumably fertile couples.
Prospective observational study of 200 couples desiring to achieve pregnancy over 12 menstrual cycles coupled with pregnancy outcome follow-up.
A university-based obstetrics and gynecological center.
Personal interviews and questionnaires were used to screen couples for entry into the study. Couples were counseled to have intercourse centered on predicted day of ovulation. Phase 1 included the first three cycles in which women collected daily morning urine samples, underwent midcycle postcoital tests, and, if late for their menses, presented for serum hCG testing. Phase 2 encompassed the next nine cycles in which women were contacted monthly by phone and underwent serum hCG testing if menses was delayed. Urine samples from cycles in which clinical (serum hCG) pregnancy did not occur underwent sensitive hCG testing to detect occult pregnancies. Pregnancies were followed until delivery to ascertain outcome.
Eighty-two percent of the 200 couples followed for the entire study period conceived. The maximal fertility rate was approximately 30% per cycle in the first two cycles. This rate quickly tapered over the remainder of the study. Pregnancy wastage during phase 1 accounted for 31% of the pregnancies detected. Forty-one percent (15/36) of these losses were seen only by urine hCG testing and were categorized as occult. Eleven of these same patients later achieved clinically recognized conceptions during the study.
These results support the concept that the efficiency of human reproduction is maximum at approximately 30% per cycle. A very significant number of these pregnancies end in spontaneous abortion. In addition, pregnancy loss before missed menses occurs in a significant proportion of women.
研究一组推测具有生育能力的夫妇的生育力及妊娠丢失率。
对200对希望在12个月经周期内受孕的夫妇进行前瞻性观察研究，并对妊娠结局进行随访。
一所大学的妇产科中心。
通过个人访谈和问卷调查筛选纳入研究的夫妇。建议夫妇在预测的排卵日前后进行性交。第一阶段包括前三个周期，在此期间女性每天采集晨尿样本，进行周期中期性交后试验，月经推迟时进行血清人绒毛膜促性腺激素（hCG）检测。第二阶段包括接下来的九个周期，在此期间每月通过电话联系女性，月经推迟时进行血清hCG检测。对未发生临床（血清hCG）妊娠周期的尿液样本进行敏感hCG检测以检测隐匿性妊娠。对妊娠进行随访直至分娩以确定结局。
在整个研究期间接受随访的200对夫妇中，82%受孕。在前两个周期中，最大受孕率约为每个周期30%。在研究的剩余时间里，这一比率迅速下降。第一阶段的妊娠丢失占检测到妊娠的31%。这些丢失中有41%（15/36）仅通过尿液hCG检测发现，归类为隐匿性妊娠。其中11名患者后来在研究期间实现了临床认可的妊娠。
这些结果支持了人类生殖效率在每个周期约30%时最高的观点。这些妊娠中有相当数量以自然流产告终。此外，相当比例的女性在月经推迟前发生妊娠丢失。
