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3
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| TI |
Alcohol, smoking, and incidence of spontaneous abortions in the first and second trimester.
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| AU |
Harlap S; Shiono PH
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Lancet 1980 Jul 26;2(8187):173-6.
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32,019 women completed a questionnaire on alcohol use at their first antenatal visit; thereafter they were followed to assess the incidence of spontaneous abortions. 51.7% reported drinking no alcohol in early pregnancy; 44.7% had less than 1 drink daily; and 2.4, 0.4, and 0.1% had an average of 1-2, 3-5, or more than 6 drinks respectively. Life-table analysis showed that the age-adjusted relative risks of second-trimester losses (15-27 weeks) were 1.03 (not significant: ns), 1.98 (p<.01), and 3.53 (p<.01) for women taking less than 1, 1-2, and more than 3 drinks daily, compared with non-drinkers. The corresponding relative risks for first-trimester losses (5-14 weeks) were 1.12 (ns), 1.15(ns), and 1.15(ns). Smokers had relative risks of 1.01(ns) and 1.21(ns) in the first and second trimesters, compared with non-smokers. The increased risk of second-trimester miscarriage in drinkers was not explained by age, parity, race, marital status, smoking, or the number of previous spontaneous or induced abortions. Thus alcohol may harm human fetuses not only when it is abused but also when taken in moderation.
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| AD |
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| PMID |
6105340
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4
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| TI |
Incidence of early loss of pregnancy.
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| AU |
Wilcox AJ; Weinberg CR; O'Connor JF; Baird DD; Schlatterer JP; Canfield RE; Armstrong EG; Nisula BC
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N Engl J Med 1988 Jul 28;319(4):189-94.
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We studied the risk of early loss of pregnancy by collecting daily urine specimens from 221 healthy women who were attempting to conceive. Urinary concentrations of human chorionic gonadotropin (hCG) were measured for a total of 707 menstrual cycles with use of an immunoradiometric assay that is able to detect hCG levels as low as 0.01 ng per milliliter, with virtually 100 percent specificity for hCG in the presence of luteinizing hormone. Our criterion for early pregnancy--an hCG level above 0.025 ng per milliliter on three consecutive days--was determined after we compared the hCG levels in the study group with the levels in a comparable group of 28 women who had undergone sterilization by tubal ligation. We identified 198 pregnancies by an increase in the hCG level near the expected time of implantation. Of these, 22 percent ended before pregnancy was detected clinically. Most of these early pregnancy losses would not have been detectable by the less sensitive assays for hCG used in earlier studies. The total rate of pregnancy loss after implantation, including clinically recognized spontaneous abortions, was 31 percent. Most of the 40 women with unrecognized early pregnancy losses had normal fertility, since 95 percent of them subsequently became clinically pregnant within two years.
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| AD |
Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, NC 27709.
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| PMID |
3393170
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5
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Conception, early pregnancy loss, and time to clinical pregnancy: a population-based prospective study.
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Wang X; Chen C; Wang L; Chen D; Guang W; French J
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| SO |
Fertil Steril 2003 Mar;79(3):577-84.
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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<or =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.
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| AD |
Department of Pediatrics, Boston University School of Medicine and BostonMedical Center, Massachusetts, USA. xbwang@bu.edu
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| PMID |
12620443
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7
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| TI |
Survival probability of human conceptions from fertilization to term.
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| AU |
Boklage CE
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| SO |
Int J Fertil 1990 Mar-Apr;35(2):75, 79-80, 81-94.
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Preterm death of the human conceptus is common. A consistent biphasic pattern in the rate of loss from biochemical pregnancy detection to term suggests that most wastage occurs prior to clinical recognition. After simple adjustments for varying methods, existing data show that at least 73% of natural single conceptions have no real chance of surviving 6 weeks of gestation. Of the remainder, about 90% will survive to term. IVF conceptions do nearly as well as natural pregnancies after clinical recognition, but poorly before, despite selecting apparently normal embryos for transfer. Reasons may lie in the uterus more than the embryo itself. Multiple pregnancies may constitute more than 12% of all natural conceptions, of which number about 2% survive to term as twins and about 12% result in single births. In all of these situations, simple equations for exponential decay in a mixture of two populations can accurately describe the distribution of those deaths in time.
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| AD |
Genetics Program, East Carolina University School of Medicine, Greenville, North Carolina.
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| PMID |
1970983
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8
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| TI |
Estimates of human fertility and pregnancy loss.
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| AU |
Zinaman MJ; Clegg ED; Brown CC; O'Connor J; Selevan SG
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| SO |
Fertil Steril 1996 Mar;65(3):503-9.
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OBJECTIVE: To examine the fertility and pregnancy wastage rates in a group of presumably fertile couples. DESIGN: Prospective observational study of 200 couples desiring to achieve pregnancy over 12 menstrual cycles coupled with pregnancy outcome follow-up. SETTING: A university-based obstetrics and gynecological center. PATIENTS: 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. RESULTS: 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. CONCLUSIONS: 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.
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| AD |
Georgetown University Medical Center, Washington, D.C., USA.
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| PMID |
8774277
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9
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Secretion and excretion of human chorionic gonadotropin during early pregnancy.
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| AU |
Lohstroh PN; Overstreet JW; Stewart DR; Nakajima ST; Cragun JR; Boyers SP; Lasley BL
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| SO |
Fertil Steril 2005 Apr;83(4):1000-11.
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OBJECTIVE: To characterize the profiles of human chorionic gonadotropin (hCG) secretion in blood and its subsequent excretion in urine during conceptive cycles that ended in successful pregnancy and in spontaneous abortion. DESIGN: A prospective study. SETTING: University fertility clinic and research laboratories. PATIENT(S): Healthy, spontaneously ovulating women with regular menses, no history of infertility, and either no male partner or an azoospermic partner. INTERVENTION(S): Blood and urine samples were collected daily from 63 spontaneously ovulating women during 167 cycles of artificial insemination (AI) with donor semen; hCG concentrations were measured in blood and urine, and luteinizing hormone (LH) and follicle-stimulating hormone (FSH) concentrations were measured in blood by immunoassay. MAIN OUTCOME MEASURE(S): Fecundity, the day of ovulation, the day of hCG detection, and the concentration of hCG on the day of detection in blood and urine. RESULT(S): In 62 conceptions detected, 14 resulted in clinical spontaneous abortion (CAB) and 8 resulted in early pregnancy loss (EPL). When successful pregnancies and pregnancy losses were compared, no significant differences existed between the days of hCG appearance in serum or in urine, the concentrations of hCG on the day of detection, or the incremental change in hCG concentration on the day of detection. CONCLUSION(S): These data validate the use of urinary hCG as a biomarker for assessing peri-implantation pregnancy events.
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| AD |
Center for Health and the Environment, University of California, Davis, California.
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| PMID |
15820813
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