TY - JOUR
T1 - Conception, early pregnancy loss, and time to clinical pregnancy
T2 - A population-based prospective study
AU - Wang, Xiaobin
AU - Chen, Changzhong
AU - Wang, Lihua
AU - Chen, Dafang
AU - Guang, Wenwei
AU - French, Jonathan
AU - Xu, Xiping
N1 - Funding Information:
This is a part of a prospective reproductive health study funded by the National Institutes of Health among women textile workers in Anhui, China. The study protocols were approved by the human subject committee of the Chinese institutions involved in the study and by the institutional review board of the Harvard School of Public Health.
PY - 2003/3/1
Y1 - 2003/3/1
N2 - Objective: To examine rates of conception and pregnancy loss and their relations with time to clinical pregnancy and reproductive outcomes. Design: A prospective observational study. Setting: Population-based cohort in China. Patient(s): Five hundred eighteen healthy newly married women who intended to conceive. Upon stopping contraception, daily records of vaginal bleeding and daily first-morning urine specimens were obtained for ≤1 year or until a clinical pregnancy was achieved. Daily urinary hCG was assayed to detect early pregnancy loss (EPL). Intervention(s): None. Main Outcome Measure(s): Conception, pregnancy loss, and time to clinical pregnancy. Result(s): The conception rate per cycle was 40% over the first 12 months. Of the 618 detectable conceptions, 49 (7.9%) ended in clinical spontaneous abortion, and 152 (24.6%) in EPL. Early pregnancy loss was detected in 14% of all the cycles without clinically recognized pregnancy, but the frequencies were lower among women with delayed time to clinical pregnancy. Early pregnancy loss in the preceding cycle was associated with increased odds of conception (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.8-3.9), clinical pregnancy (OR, 2.0; 95% CI, 1.3-3.0), and EPL (OR, 2.4; 95% CI, 1.4-4.2) but was not associated with spontaneous abortion, low birth weight, or preterm birth in the subsequent cycle. Conclusion(s): We demonstrated substantial EPL in the non-clinically pregnant cycles and a positive relation between EPL and subsequent fertility.
AB - Objective: To examine rates of conception and pregnancy loss and their relations with time to clinical pregnancy and reproductive outcomes. Design: A prospective observational study. Setting: Population-based cohort in China. Patient(s): Five hundred eighteen healthy newly married women who intended to conceive. Upon stopping contraception, daily records of vaginal bleeding and daily first-morning urine specimens were obtained for ≤1 year or until a clinical pregnancy was achieved. Daily urinary hCG was assayed to detect early pregnancy loss (EPL). Intervention(s): None. Main Outcome Measure(s): Conception, pregnancy loss, and time to clinical pregnancy. Result(s): The conception rate per cycle was 40% over the first 12 months. Of the 618 detectable conceptions, 49 (7.9%) ended in clinical spontaneous abortion, and 152 (24.6%) in EPL. Early pregnancy loss was detected in 14% of all the cycles without clinically recognized pregnancy, but the frequencies were lower among women with delayed time to clinical pregnancy. Early pregnancy loss in the preceding cycle was associated with increased odds of conception (odds ratio [OR], 2.6; 95% confidence interval [CI], 1.8-3.9), clinical pregnancy (OR, 2.0; 95% CI, 1.3-3.0), and EPL (OR, 2.4; 95% CI, 1.4-4.2) but was not associated with spontaneous abortion, low birth weight, or preterm birth in the subsequent cycle. Conclusion(s): We demonstrated substantial EPL in the non-clinically pregnant cycles and a positive relation between EPL and subsequent fertility.
KW - Conception
KW - Early pregnancy loss
KW - Human chorionic gonadotropin (hCG)
KW - Prospective study
KW - Time to clinical pregnancy
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U2 - 10.1016/S0015-0282(02)04694-0
DO - 10.1016/S0015-0282(02)04694-0
M3 - Article
C2 - 12620443
AN - SCOPUS:0037338008
SN - 0015-0282
VL - 79
SP - 577
EP - 584
JO - Fertility and sterility
JF - Fertility and sterility
IS - 3
ER -