Breast cancer in relation to the occurrence and time of induced and spontaneous abortion

The authors evaluated whether an induced or spontaneous abortion during the first six months of gestation, particularly if it occurs before the first term pregnancy, increases the risk of breast cancer. Data from a case-control study of women under 70 years of age were used: 3,200 cases of breast cancer were compared with 4,844 controls with nonmalignant nongynecologic conditions. Among both nulliparous and parous women, the risk of breast cancer was not related to the number of induced or spontaneous abortions. After allowance for all identified potential confounding factors, the estimated relative risk for nulliparous women with an induced abortion relative to those who had never been pregnant was 1.3 (95% confidence interval (CI) 0.8-2.2), and for spontaneous abortion, the corresponding estimate was 0.9 (95% CI 0.5-1.5). Among parous women, the estimated relative risks were 1.2 (95% CI 0.9-1.6) for an induced abortion and 0.9 (95% CI 0.8-1.0) for a spontaneous abortion, relative to never having had an abortion of any type. The time of the abortion had little effect: The relative risk estimates were 0.9 (95% CI 0.5-1.4) for induced abortion before the first term birth, 1.4 (95% CI 1.0-1.9) for induced abortion first occurring after the first term birth, 0.9 (95% CI 0.7-1.2) for spontaneous abortion before the first term birth, and 0.9 (95% CI 0.7-1.0) for spontaneous abortion first occurring after the first term birth. Similar results were evident for women under age 40, among whom the frequency of induced abortion was relatively high. These data suggest that the risk of breast cancer is not materially affected by abortion, regardless of whether it occurs before or after the first term birth.     

Exposure to phenoxy herbicides and the risk of spontaneous abortion.

The Ontario Farm Family Health Study was designed to assess retrospectively the potential adverse effects of exposure to pesticides on pregnancy. Information on the health and life style of approximately 2,000 farm couples, as well as a history of use of pesticides on the farm, was collected by questionnaire. This analysis focuses on pre- and postconception exposure to phenoxy herbicides and the risk of spontaneous abortion using the complete (to date) pregnancy history for each woman. Preconception exposure (from 3 months before conception to the month of conception) was weakly associated with the risk of spontaneous abortion at <20 weeks' gestation [adjusted odds ratio (OR) = 1.1; 95% confidence interval (CI) = 0.6-1.9]. When the analyses were restricted to spontaneous abortions of <12 weeks, the risk was more than doubled (adjusted OR = 2.5; 95% CI = 1.0-6.4), but the results were sensitive to the cutpoint used. If the husband did not normally wear protective equipment during application, the crude OR for early spontaneous abortions was 5.0 (95% CI = 0.7-36.2). Exposure to phenoxy herbicides during the first trimester was generally not associated with increased risk of spontaneous abortion. The results suggest a possible role of preconception (possibly paternal) exposures to phenoxy herbicides in the risk of early spontaneous abortions.     

Parental occupational exposure to pesticides and childhood germ-cell tumors

In a recently completed US case-control study (Children's Oncology Group, 1993-2001) with 253 cases and 394 controls, the authors investigated the association between parental occupational exposure to pesticides and risk of childhood germ-cell tumors. Information on occupational pesticide exposure was collected using job-specific module questionnaires and assessed by an experienced industrial hygienist. Odds ratios for childhood germ-cell tumors associated with maternal exposures before pregnancy, during pregnancy, and after the birth of the index child were 1.0 (95% confidence interval (CI): 0.8, 1.4), 1.1 (95% CI: 0.7, 1.6), and 1.3 (95% CI: 0.9, 1.8), respectively. Paternal exposures before pregnancy, during pregnancy, and after the birth of the index child were not related to germ-cell tumors (odds ratios (ORs) were 0.9 (95% CI: 0.7, 1.2), 0.8 (95% CI: 0.5, 1.2), and 0.8 (95% CI: 0.5, 1.3), respectively). When both parents had ever been occupationally exposed to pesticides before the index pregnancy, the odds ratio was 0.8 (95% CI: 0.4, 1.3). Subgroup analyses showed a positive association between maternal exposure to herbicides during the postnatal period and risk of germ-cell tumors in girls (OR = 2.3, 95% CI: 1.0, 5.2) and an inverse association between paternal exposure to pesticides during the index pregnancy and germ-cell tumors in boys (OR = 0.2, 95% CI: 0.1, 1.0). This study did not provide strong evidence supporting a relation between parental pesticide exposure in the workplace and risk of germ-cell tumors among offspring.     

Paternal and Maternal Smoking Habits before Conception and During the First Trimester: Relation to Spontaneous Abortion

PURPOSE: This study examined the association between maternal smoking before and during the first trimester of pregnancy and spontaneous abortion.

METHODS: We have been conducting a hospital-based case-control study on risk factors for spontaneous abortion in the greater Milan area. We collected information from 782 cases of spontaneous abortions and 1543 controls (women who delivered at term healthy infants).

RESULTS: With respect to never smokers, the odds ratio (OR) were 0.7 (95%, confidence interval (CI), 0.5–1.0) for women who quit smoking and 1.3 (95% CI, 1.0–1.6) for those who continued during pregnancy. Women who smoked more than 10 cigarettes/day in the first trimester were at increased risk of miscarriage, with an OR of 1.4 (95% CI, 1.0–2.1). No relationship was evident between the number of cigarettes smoked before conception and the risk of abortion. Likewise, no association emerged between paternal smoking and miscarriage. Moreover, no significant interaction or modification effect was obtained when strata of age and other major characteristics were investigated.

CONCLUSIONS: The risk of abortion associated with cigarette smoking during the first trimester of pregnancy was measurable and noticeable in this population, and accounted for 9% (95% CI, 6–13%) of all cases. The increased risk of spontaneous abortion in women smoking during pregnancy is a further reason to encourage pregnant women to quit.     

Spontaneous abortion and maternal work in greenhouses

BACKGROUND: A positive association between maternal occupational exposure to pesticide and spontaneous abortion has been reported in some studies. Work in greenhouses may imply exposure of pregnant women to pesticides continuously and at elevated level. METHODS: A total of 717 women working in greenhouses provided information on 973 pregnancies, including 110 spontaneous abortions. These pregnancies were classified as exposed or not exposed according to maternal occupation, re-entry activities and application of pesticides in greenhouses during at least 1 month in the first trimester of pregnancy. The ORs for spontaneous abortion were estimated through a generalised estimate equations model for all orders of pregnancy together, and through a logistic regression model limited to first pregnancies. RESULTS: Increased risks of spontaneous abortion were found for maternal re-entry activities within 24 hr after pesticides were applied (all orders of pregnancy: OR 3.2, 95% CI 1.3-7.7; first pregnancies: OR 3.8, 95% CI 1.0-13.9) and for those who applied pesticides (all orders of pregnancy: OR 2.6, 95% CI 1.0-6.6; first pregnancies: OR 3.7, 95% CI 0.7-20,6) CONCLUSIONS: The observed results support the hypothesis of an association between maternal work in greenhouses and spontaneous abortion. The main limitations of the study are lack of information on the specific chemicals used and the small number of pregnancies heavily exposed to pesticides.     

Risk factors for ectopic pregnancy: a comprehensive analysis based on a large case-control,population-based study in France

This case-control study was associated with a regional register of ectopic pregnancy between 1993 and 2000 in France. It included 803 cases of ectopic pregnancy and 1,683 deliveries and was powerful enough to investigate all ectopic pregnancy risk factors. The main risk factors were infectious history (adjusted attributable risk = 0.33; adjusted odds ratio for previous pelvic infectious disease = 3.4, 95% percent confidence interval (CI): 2.4, 5.0) and smoking (adjusted attributable risk = 0.35; adjusted odds ratio = 3.9, 95% CI: 2.6, 5.9 for >20 cigarettes/day vs. women who had never smoked). The other risk factors were age (associated per se with a risk of ectopic pregnancy), prior spontaneous abortions, history of infertility, and previous use of an intrauterine device. Prior medical induced abortion was associated with a risk of ectopic pregnancy (adjusted odds ratio = 2.8, 95% CI: 1.1, 7.2); no such association was observed for surgical abortion (adjusted odds ratio = 1.1, 95% CI: 0.8, 1.6). The total attributable risk of all the factors investigated was 0.76. As close associations were found between ectopic pregnancy and infertility and between ectopic pregnancy and spontaneous abortion, further research into ectopic pregnancy should focus on risk factors common to these conditions. In terms of public health, increasing awareness of the effects of smoking may be useful for ectopic pregnancy prevention.     

The use of electric bed heaters and the risk of clinically recognized spontaneous abortion

We conducted a prospective cohort study to evaluate the relation of spontaneous abortion and electric bed heater use during the first trimester of pregnancy. Compared with non-users, rates of spontaneous abortion were lower for women who used electric bed heaters. The adjusted odds ratio and 95% confidence interval (CI) for the two major devices used, electric blankets (N = 524) and waterbeds (N = 796), were, respectively, 0.8 (95% CI = 0.5-1.1) and 0.9 (95% CI = 0.7-1.2). An increase of risk with increasing intensity (setting-duration combination) of use was not observed. Users of electric blankets at low settings for most of the night (N = 171) had lower risks of spontaneous abortion than non-users (adjusted odds ratio = 0.5; 95% CI = 0.3-1.0). Twenty women who used electric blankets at a high setting for 1 hour or less had an adjusted odds ratio of 3.0 (95% CI = 1.1-8.3), but we found no spontaneous abortions among the few women (N = 13) who used a high setting for 2 or more hours. We found that exposure rankings of the magnetic field time-weighted average and a rate of change metric did not correspond monotonically to the pattern of spontaneous abortion risks and that electric blankets contribute less to overnight time-weighted average magnetic fields than has been thought.     

Preconception B-vitamin and homocysteine status, conception, and early pregnancy loss

Maternal vitamin status contributes to clinical spontaneous abortion, but the role of B-vitamin and homocysteine status in subclinical early pregnancy loss is unknown. Three-hundred sixty-four textile workers from Anqing, China, who conceived at least once during prospective observation (1996-1998), provided daily urine specimens for up to 1 year, and urinary human chorionic gonadotropin was assayed to detect conception and early pregnancy loss. Homocysteine, folate, and vitamins B6 and B12 were measured in preconception plasma. Relative to women in the lowest quartile of vitamin B6, those in the third and fourth quartiles had higher adjusted proportional hazard ratios of conception (hazard ratio (HR)=2.2, 95% confidence interval (CI): 1.3, 3.4; HR=1.6, 95% CI: 1.1, 2.3, respectively), and the adjusted odds ratio for early pregnancy loss in conceptive cycles was lower in the fourth quartile (odds ratio=0.5, 95% CI: 0.3, 1.0). Women with sufficient vitamin B6 had a higher adjusted hazard ratio of conception (HR=1.4, 95% CI: 1.1, 1.9) and a lower adjusted odds ratio of early pregnancy loss in conceptive cycles (odds ratio=0.7, 95% CI: 0.4, 1.1) than did women with vitamin B6 deficiency. Poor vitamin B6 status appears to decrease the probability of conception and to contribute to the risk of early pregnancy loss in this population.     

Occupational exposures and ovarian cancer in textile workers

BACKGROUND: Occupational risk factors for ovarian cancer have been investigated only to a limited extent. We conducted a case-cohort study to examine associations between occupational exposures and ovarian cancer in the textile industry. METHODS: We compared 261 incident ovarian cancer cases diagnosed between 1989 and 1998 with an age-stratified reference subcohort (n = 3199) from a cohort of 267,400 textile workers in Shanghai, China. Occupational exposures were assessed by job-exposure matrices designed for the textile industry, and estimates of quantitative cotton dust and endotoxin. We calculated hazard ratios (HRs) and 95% confidence intervals (CIs) with Cox proportional hazards modeling adapted for the case-cohort design. RESULTS: A decreased risk of ovarian cancer was associated with ever having worked in cotton manufacturing production (HR = 0.7; 95% CI = 0.4-1.0). An increased risk was associated with ever having worked in textile finishing (2.1; 0.9-5.0). We found an increasing risk of ovarian cancer associated with cumulative exposure to silica dust (for <10 years exposure, HR = 6.8 [CI = 0.6-76]; for > or =10 years, 5.6 [1.3-23.6]), although these results are based on only 8 exposed subcohort women (0.3%) and 4 cases (1.3%). We also detected inverse risk gradients for cumulative exposures to endotoxin when exposures were lagged by 20 years (in highest quartile, HR = 0.6 [CI = 0.4-1.1]). CONCLUSION: Silica dust may increase the risk of ovarian cancer, and cotton dust and endotoxin may reduce risk.     

Risk of ectopic pregnancy and previous induced abortion.

OBJECTIVES: This study investigated the role of prior history of induced abortion in subsequent ectopic pregnancies. METHODS: Data from two French case-control studies were used to examine the effect of induced abortion on ectopic pregnancy risk. Case patients (n = 570) were women admitted for ectopic pregnancy during the study period; controls (n = 1385) were women who delivered in the same center. RESULTS: The analysis among women with no previous ectopic pregnancy showed that, after control for the main ectopic pregnancy risk factors, prior induced abortion was associated with an increased risk of ectopic pregnancy (odds ratio [OR] = 1.5, 95% confidence interval [CI] = 1.0, 2.0); there was a significant trend between number of previous induced abortions and ectopic pregnancy risk (ORs = 1.4 for 1 previous induced abortion and 1.9 for 2 or more). CONCLUSIONS: This study suggests that induced abortion may be a risk factor for ectopic pregnancy for women with no previous ectopic pregnancy, particularly in the case of women who have had several induced abortions.     

Menstrual cycle characteristics: associations with fertility and spontaneous abortion

BACKGROUND: Epidemiologists often use menstrual cycle patterns as indicators of endocrine function in environmental and occupational studies, yet few studies have considered whether menstrual cycle characteristics are associated with fertility or pregnancy outcome. METHODS: We prospectively studied 470 women to determine whether cycle length or bleed length were associated with fertility or spontaneous abortion. Women completed daily diaries with information on menstrual bleeding, intercourse, birth control use, and covariates. For each menstrual cycle, women collected at least 2 urine samples, which were assayed for human chorionic gonadotropin to define early pregnancies. Women were followed for 1 year or until the end of a clinical pregnancy. RESULTS: Cycles with lengths of 30 to 31 days preceded cycles with the highest fecundity. Shorter cycles were less likely to be followed by conception (fecundity ratio [FR] = 0.6; 95% confidence interval [CI] = 0.4-1.0). Compared with 30- to 31-day cycles, conceptions after shorter and longer cycles were more likely to be spontaneously aborted (for shorter cycles, odds ratio [OR] = 3.0 [95% CI = 0.9-9.6] and for longer cycles, OR = 3.0 [0.9-10.6]). Cycles with 5 days of menstrual bleeding had the highest fecundity. Cycles with up to 4 days of bleeding had lower fecundity (for bleed lengths of 4 days, FR = 0.5 [0.3-0.8] and for bleed lengths less than 4 days, FR = 0.6 [0.3-0.9]). Spontaneous abortion was less likely after bleeds greater than 5 days (OR = 0.4 [0.1-1.1]) when compared with 5-day bleeds. CONCLUSIONS: Menstrual cycle characteristics appear to be associated with fertility and spontaneous abortion.     

Marijuana and spontaneous abortion of known karyotype

We tested whether marijuana use in the 2 months before the last menstrual period and during pregnancy affects the risk of spontaneous abortions of known karyotype. Spontaneous abortions (cases) were defined as chromosomally normal (n = 567) or chromosomally aberrant (n = 393) and, within the latter, by type of aberration (212 trisomies, 71 monosomies X, 49 triploidies, 61 others). Controls were women with prenatal care before 22 weeks gestation and delivering at 28 weeks or later (n = 2042). In comparison with controls, adjusted odds (OR) of reported marijuana use in chromosomally normal cases were 1.1 (95% confidence interval (CI) 0.7, 1.5) and in chromosomally aberrant cases combined 1.2 (95% CI 0.7, 1.9). With respect to specific aberrations, use in the perifertilisation period did not differ significantly from that in controls for trisomies (adjusted OR = 0.8, 95% CI 0.4, 1.8), monosomies X (adjusted OR = 1.8, 95% CI 0.7, 4.3), and triploidies (adjusted OR = 1.3, 95% CI 0.4, 4.5). Comparison of karyotype groups with each other yielded similar results. Our data do not support causal associations of marijuana use, at the levels represented in our sample, with either chromosomally normal or trisomic spontaneous abortion. With monosomy X and triploidy, no statistically significant associations were detected although numbers were insufficient to rule out moderate effects.     

Potential for bias in waiting time studies: events between enrolment and admission

STUDY OBJECTIVE: To demonstrate the effect of exclusion of data on delays in scheduling operations in calculating difference in admission rates between two enrolment periods. DESIGN: A prospective cohort study; outcome measure-waiting time for elective admission; study variables-enrolment periods, before 31 March 1997 and after that date; the time of scheduling delay; gender; age; urgency, and type of surgery. SETTING: An acute care hospital in Ontario, Canada. PARTICIPANTS: 1173 consecutive cases accepted for elective vascular surgery between 1 July 1994 and 31 March 1999. MAIN RESULTS: Before adjustment for scheduling delays, a 20% lower admission rate was associated with period 2, rate ratio (RR) = 0.8 (95% confidence intervals (CI)= 0.7, 0.9). The difference between the periods became only marginally significant after the adjustment, RR = 0.9 (95% CI=0.8, 1.0). No difference between the periods was found when admission rates were compared before a delay occurred, RR = 0.9 (95% CI=0.8, 1.1). In delayed patients, those enrolled in period 1 and 2 had, respectively, a 40% and a 60% lower admission rate than the period 1 patients admitted without scheduling delays, RR = 0.6 (95% CI=0.4, 0.8) for period 1 and RR = 0.4 (95%CI=0.3, 0.5) for period 2. CONCLUSIONS: The results provide evidence that patients experiencing a delay in scheduling operation have a lower admission rate after the event. Thus, potential for bias exists when between group comparison of waiting time is done without adjustment for an intermediate event that may occur before elective admission.     

Joint effect of cigarette smoking and alcohol consumption on mortality

OBJECTIVE: To evaluate the joint effect of cigarette smoking and alcohol consumption on mortality. METHODS: A population-based cohort of 66,743 Chinese men aged 30-89 in Shanghai, China recruited from 1996 to 2000. Lifestyle data were collected using structured questionnaires. As of November 2004, follow-up for the vital status of 64,515 men was completed and death information was further confirmed through record linkage with the Shanghai Vital Statistics Registry. Associations were evaluated by Cox regression analyses. RESULTS: 2514 deaths (982 from cancers, 776 from cardiovascular diseases (CVD)) were identified during 297,396 person-years of follow-up. Compared to never-smokers, both former and current smokers had significantly elevated mortality from any cause, CVD, and cancer; risk increased with amount of smoking. Intake of 1-7 drinks/week was associated with reduced risk of death, particularly CVD death (hazard ratio (HR): 0.7, 95% confidence interval (CI): 0.5, 1.0), whereas intake of >42 drinks/week was related to increased mortality, particularly cancer-related death (HR: 1.7, 95% CI: 1.1, 2.5). The HR for total mortality associated with moderate alcohol consumption increased from 0.8 (95% CI: 0.6, 1.0) for non-smokers to 1.0 (0.9, 1.2) for moderate smokers and 1.4 (95% CI: 1.2, 1.7) for heavy smokers. Heavy drinkers and heavy smokers had the highest mortality (HR: 1.9, 95% CI: 1.6, 2.4). CONCLUSIONS: Light and moderate alcohol consumption reduced mortality from CVD. This beneficial effect, however, was offset by cigarette smoking.     

Ectopic pregnancy and prior induced abortion.

We compared the prior pregnancy histories of 85 multigravid women with an ectopic pregnancy and 498 multigravid delivery comparison subjects. We found a relationship between the number of prior induced abortions and the risk of ectopic pregnancy: the crude relative risk of ectopic pregnancy was 1.6 for women with one prior induced abortion and 4.0 for women with two or more prior induced abortions; however, use of multivariate techniques to control confounding factors reduced the relative risks to 1.3 (95 per cent confidence interval, 0.6-2.7) and 2.6 (95 per cent confidence interval, 0.9-7.4), respectively. The analysis suggests that induced abortion may be one of several risk factors for ectopic pregnancy, particularly for women who have had abortions plus pelvic inflammatory disease or multiple abortions.     

Alcoholic beverages and incidence of dementia: 34-year follow-up of the prospective population study of women in Goteborg

The objective of this study was to assess the association between different types of alcoholic beverages and 34-year incidence of dementia. Among a random sample of 1,462 women aged 38-60 years and living in G?teborg, Sweden, in 1968-1969, 164 cases of dementia were diagnosed by 2002. At baseline as well as in 1974-1975, 1980-1981, and 1992-1993, the frequency of alcohol intake, as well as other lifestyle and health factors, was recorded and related to dementia with Cox proportional hazard regression, by use of both baseline and updated covariates. Wine was protective for dementia (hazard ratio (HR) = 0.6, 95% confidence interval (CI): 0.4, 0.8) in the updated model, and the association was strongest among women who consumed wine only (HR = 0.3, 95% CI: 0.1, 0.8). After stratification by smoking, the protective association of wine was stronger among smokers. In contrast, consumption of spirits at baseline was associated with slightly increased risk of dementia (HR = 1.5, 95% CI: 1.0, 2.2). Results show that wine and spirits displayed opposing associations with dementia. Because a protective effect was not seen for the other beverages, at least part of the association for wine may be explained by components other than ethanol.     

Dietary behaviors, physical activity, and cigarette smoking among pregnant Puerto Rican women

BACKGROUND: Few studies have examined predictors of meeting health guidelines in pregnancy among Latina women. OBJECTIVE: We assessed dietary behaviors, physical activity, and cigarette smoking in the Latina Gestational Diabetes Mellitus Study, a prospective cohort of 1231 prenatal care patients. DESIGN: Self-reported information on lifestyle factors, demographics, medical history, and physical activity was collected by bilingual interviewers during pregnancy. Fruit/vegetable intake was determined by summing the reported consumption of specific fruit and vegetables on a food-frequency questionnaire designed for this population and then adjusted for reported total daily servings. RESULTS: Approximately 13% of women met physical activity guidelines [>or=10 metabolic equivalents (MET)-h/wk], 19% met fruit/vegetable guidelines (7 servings/d), 21% of women smoked, and 1.4% consumed alcohol during pregnancy. In multivariate analyses, Spanish-language preference, an indicator of less acculturation, was associated with an approximately 40% less likelihood of both smoking [odds ratio (OR): 0.6; 95% CI: 0.4, 0.8] and meeting physical activity guidelines (OR: 0.6; 95% CI: 0.3, 1.0). College education was associated with a 2-fold greater likelihood of meeting fruit/vegetable guidelines (OR: 2.2; 95% CI: 1.1, 4.3) and a lower likelihood of smoking (OR: 0.2; 95% CI: 0.1, 0.4). A history of adverse pregnancy outcome was associated with a >4-fold greater likelihood of meeting physical activity guidelines. Smoking in pregnancy was associated with a decreased likelihood of meeting the fruit/vegetable guidelines (RR: 0.5; 95% CI: 0.3, 0.9). CONCLUSION: Factors related to engagement in prenatal health behaviors should be addressed in the design of targeted intervention strategies in this underserved and rapidly growing population.     

Work schedule during pregnancy and spontaneous abortion

BACKGROUND: There is inconsistent evidence as to whether work schedule (including rotating shifts and night work) can affect reproductive outcomes. METHODS: We investigated the association between work schedule and risk of spontaneous abortion in U.S. nurses. The Nurses' Health Study II is a prospective cohort study established in 1989. In 2001, information about occupational activities and exposures during pregnancy was collected from female nurses for the most recent pregnancy since 1993. Of 11,178 eligible respondents, 9547 (85%) indicated willingness to participate in the occupational study, and 8461 of those (89%) returned the questionnaire, for an overall participation rate of 76%. Of these, 7688 women had pregnancies that were eligible for analysis. RESULTS: Participants reported 6902 live births and 786 (10%) spontaneous abortions. Compared with women who reported usually working "days only" during their first trimester, women who reported usually working "nights only" had a 60% increased risk of spontaneous abortion (RR = 1.6; 95% confidence interval [CI] = 1.3-1.9). A rotating schedule, with or without night shifts, was not associated with an increase in risk (RR = 1.2 [CI = 0.9-1.5] and 1.0 [CI = 0.8-1.2], respectively). Women who reported working more than 40 hours per week during the first trimester were also at increased risk of spontaneous abortion (1.5; 1.3-1.7) compared with women working 21-40 hours, even after adjustment for work schedule. CONCLUSIONS: Nightwork and long work hours may be associated with an increased risk of spontaneous abortion. Further studies are needed to determine whether hormonal disturbances attributed to night work affect pregnancy outcome.     

Unintended pregnancy and its risk factors among university students in eastern China

BACKGROUND: The study was conducted to determine the prevalence of unintended pregnancy, induced abortion and contraceptive use, and factors associated with unintended pregnancy among Chinese university students. STUDY DESIGN: A self-administered questionnaire survey with cross-sectional design was administered among students in two universities in Ningbo, China, in November-December 2003. Sociodemographic and behavioral factors associated with unintended pregnancy were identified in both genders using univariate and multivariate analyses. RESULTS: Of sexually active students, 10.6% of male and 11.6% of female students reported their partner or they had a history of pregnancy; 10.0% of male and 11.3% of female students reported their partner or they had a history of induced abortion. The risk factors for unintended pregnancy identified among males by multivariate analysis were older age [odds ratio (OR), 2.12; 95% confidence interval (CI), 1.15-3.88], initiation of sexual activity before high school (OR, 2.45; 95% CI, 1.36-4.44), reported lack of condom use in first sexual activity (OR, 1.71; 95% CI, 1.10-2.64), multiple sexual partners (OR, 1.54; 95% CI, 1.06-2.23), and often used condoms during their lifetime (OR, 1.97; 95% CI, 1.01-3.81). The identified risk factors among females were initiation of sexual activity before high school (OR, 5.12; 95% CI, 1.49-17.68), non-consensual sexual intercourse as first sex (OR, 1.77; 95% CI, 1.08-2.90), multiple partners (OR, 2.75; 95% CI, 1.61-4.71), and sometimes/never (OR, 3.02; 95% CI, 1.16-7.87) or often (OR, 3.92; 95% CI, 1.43-10.73) used condoms during their lifetime. CONCLUSION: The high prevalence of unintended pregnancies and induced abortions in this population indicates a need for better and targeted sex education and family planning services.