Pregnancy outcomes, infant mortality, and arsenic in drinking water in West Bengal, India

Between 2001 and 2003, the authors studied pregnancy outcomes and infant mortality among 202 married women in West Bengal, India. Reproductive histories were ascertained using structured interviews. Arsenic exposure during each pregnancy, including all water sources used, was assessed; this involved measurements from 409 wells. Odds ratios for spontaneous abortion, stillbirth, neonatal mortality, and infant mortality were estimated with logistic regression based on the method of generalized estimating equations. Exposure to high concentrations of arsenic (> or =200 microg/liter) during pregnancy was associated with a sixfold increased risk of stillbirth after adjustment for potential confounders (odds ratio (OR) = 6.07, 95% confidence interval (CI): 1.54, 24.0; p = 0.01). Arsenic-related skin lesions were found in 12 women who had a substantially increased risk of stillbirth (OR = 13.1, 95% CI: 3.17, 54.0; p = 0.002). The odds ratio for neonatal death was 2.81 (95% CI: 0.73, 10.8). No association was found between arsenic exposure and spontaneous abortion (OR = 1.01, 95% CI: 0.38, 2.70) or overall infant mortality (OR = 1.33, 95% CI: 0.43, 4.04). This study adds to the limited evidence that exposure to high concentrations of arsenic during pregnancy increases the risk of stillbirth. However, there was no indication of the increased rates of spontaneous abortion and overall infant mortality that have been reported in some studies.     

Relations of gestational length and timing and type of incomplete pregnancy to ovarian cancer risk

While the protective nature of parity with respect to ovarian cancer has been well documented, whether a history of incomplete pregnancy affects ovarian cancer risk is uncertain. Data collected from 739 epithelial ovarian cancer cases and 1,313 community controls in the Delaware Valley from 1994 to 1998 were used to evaluate the relation between gestational length and timing of first induced or spontaneous abortion and ovarian cancer risk. Incomplete pregnancy was not associated with ovarian cancer among nulliparous women or among ever-pregnant women either before or after adjustment for relevant confounders (for nulliparous women, odds ratio (OR) = 1.12, 95% confidence interval (CI): 0.66, 1.89; for ever-pregnant women, OR = 0.95, 95% CI: 0.76, 1.18). Among unigravid women, one full-term pregnancy was more protective than an incomplete pregnancy (adjusted OR = 0.29, 95% CI: 0.15, 0.57). These results were independent of the type of pregnancy loss. Among ever-pregnant women, a spontaneous abortion before a first birth provided significant protection (adjusted OR = 0.47, 95% CI: 0.30, 0.75), while no significant effect was found for an induced abortion prior to a first birth (adjusted OR = 0.80, 95% CI: 0.44, 1.47). These data do not support an independent association between incomplete pregnancies, either spontaneous or induced, and ovarian cancer risk.     

Prior spontaneous abortion, prior elective termination, interpregnancy interval, and risk of neural tube defects

A woman with a history of spontaneous abortion in her immediately prior pregnancy may be at increased risk for a pregnancy affected by a neural tube defect (NTD). A short interpregnancy interval may further increase this risk. Using data from a population-based case-control study (1989-1991), the authors investigated NTD risk resulting from a prior spontaneous abortion or elective termination and a short interpregnancy interval. Of 538 interviewed case mothers and 539 interviewed control mothers, 408 case mothers and 433 control mothers reported having a prior pregnancy. Analysis showed a slightly decreased NTD risk among mothers whose immediately prior pregnancy had ended in a spontaneous abortion or elective termination in comparison with a live birth (odds ratio (OR) = 0.82; 95% confidence interval (CI): 0.61, 1.1). This decreased risk was consistent across strata of short or long interpregnancy intervals. Additional analysis revealed an increased NTD risk for mothers with an interpregnancy interval of < or =6 months compared with >12-< or =24 months (OR = 1.5; 95% CI: 0.93, 2.4). This latter risk was greatest among mothers whose immediately prior pregnancy had resulted in a live birth (OR = 2.0; 95% CI: 1.0, 3.8) rather than a spontaneous abortion or elective termination (OR = 0.96; 95% CI: 0.44, 2.1). Adjustment for potential covariates did not substantially alter observed risk estimates.     

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.     

Risk factors for ectopic pregnancy: a case-control study in France, with special focus on infectious factors

A case-control study was conducted in 1988 in seven Paris area maternity hospitals to evaluate the role of several risk factors, particularly infectious factors, in ectopic pregnancy. A total of 279 cases and 279 controls were compared for sociodemographic characteristics, cigarette smoking, sexual, reproductive and surgical histories, and conditions of conception. Pelvic inflammatory disease confirmed by celioscopy (odds ratio (OR) = 5.5, 95% confidence interval (CI) 2.1-13.9) and Chlamydia trachomatis seropositivity (OR = 3.9, 95% CI 2.3-6.7) appeared to be important risk factors for ectopic pregnancy. Other risk factors found to be associated with an increased risk of ectopic pregnancy were dose-related cigarette smoking at the time of conception (ORs 1.3 to 2.5), appendectomy (OR = 1.6, 95% CI 1.1-2.5), prior tubal surgery (OR = 5.1, 95% CI 1.7-15.4), induced conception cycle (OR = 3.2, 95% CI 1.1-9.3), and prior ectopic pregnancy (OR = 13.3, 95% CI 4.5-39.2). However, some of the latter risk factors, i.e., prior tubal surgery, prior ectopic pregnancy, and perhaps appendectomy, may be considered to be the results of pelvic inflammatory disease and sexually transmitted diseases. Maternal age, parity, prior induced abortion, and prior spontaneous abortion were not associated with ectopic pregnancy. Use of intrauterine device, progestagen micropill, and also combined estroprogestative pill at the time of conception were associated with a better prevention of intrauterine pregnancy than of ectopic pregnancy. These findings confirm the importance of several previously reported risk factors of ectopic pregnancy: sexually transmitted diseases, cigarette smoking, and prior ectopic pregnancy. They also identified new risk factors, appendectomy and induced conception cycle, and revealed that the combined estroprogestative pill does not prevent ectopic pregnancy as effectively as it does intrauterine pregnancy.     

Caffeine consumption during pregnancy and spontaneous abortion

We conducted a case-control study of spontaneous abortion in Santa Clara County, California between 1986 and 1987. We analyzed data on 607 cases and 1,284 controls to evaluate the potential association between caffeine consumption during the first trimester of pregnancy and spontaneous abortion. About 70% of the women consumed caffeinated coffee, tea, and/or soda; 7% of the women consumed more than an average of 300 mg of caffeine daily. The crude odds ratio (OR) for heavy caffeine consumption (greater than 300 mg/day) was 1.55 (95% CI: 1.04-2.31), which decreased to 1.22 (95% CI: 0.80-1.87) after controlling for confounding factors. For these heavy users, nausea modified the association of spontaneous abortion and caffeine; heavy caffeine consumers reporting nausea had a doubled risk for spontaneous abortion (adjusted OR = 2.10, 95% CI: 1.20-3.70), in contrast to those who did not report nausea (adjusted OR = 0.53, 95% CI: 0.27-1.04). Heavy caffeine consumers who decreased their caffeine intake early in pregnancy had a risk of spontaneous abortion similar to that of nonconsumers.     

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.     

Association of petrochemical exposure with spontaneous abortion

OBJECTIVES: To assess the association between petrochemical exposure and spontaneous abortion, a retrospective epidemiological study in a large petrochemical complex in Beijing, China was conducted. METHODS: Plant employment records identified 3105 women who were married, were 20-44 years of age, and had never smoked. Of those, 3070 women (98.8%) reported at least one pregnancy. From this group, 2853 (93%) of the women participated in the study. According to their plant employment record, about 57% of these women workers reported occupational exposure to petrochemicals during the first trimester of their pregnancy. Trained interviewers administered a standardised questionnaire to this group of women and their husbands, collecting information on reproductive history, pregnancy outcomes, employment history, occupational exposure, smoking habits, alcohol consumption, indoor air pollution, and demographic variables. The results from the womens' first pregnancies were analysed. RESULTS: There was a significantly increased risk of spontaneous abortion for women working in all of the production plants with frequent exposure to petrochemicals (8.8%; range of 5.8%-9.8%) compared with those working in nonchemical plants (2.2%; range of 0.0%-7.1%). Also, when a comparison was made between exposed and non-exposed groups within each plant, exposure to petrochemicals was consistently associated with an increased risk of spontaneous abortion. The overall odds ratio (OR) was 2.7 (95% confidence interval (95% CI) 1.8 to 3.9) after adjusting for potential confounders. When the analysis was performed with the exposure information obtained from the women' interview responses for (self reported) exposures, the estimated OR for spontaneous abortions was 2.9 (95% CI 2.0 to 4.0). The analysis was repeated by excluding those 452 women who provided inconsistent reports between recalled exposure and work history, and a comparable risk of spontaneous abortion (OR 2.9; 95% CI 2.0 to 4.4) was found. In analyses for exposure to specific chemicals, an increased risk of spontaneous abortion was found with exposure to most chemicals, and the results for benzene (OR 2.5; 95% CI 1.7 to 3.7), gasoline (OR 1.8; 95% CI 1.1 to 2.9), and hydrogen sulphide (OR 2.3; 95% CI 1.2 to 4.4) were significant. CONCLUSION: An increased risk of spontaneous abortion was found associated with the exposure to petrochemicals, including benzene, gasoline, and hydrogen sulphide.

 

     

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.     

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 abortions among Finnish flight attendants.

We conducted a retrospective cohort study to investigate whether work as a cabin attendant is related to an increased risk for spontaneous abortion. Data on female cabin crew members were linked to medical records on pregnancies. There were 1751 eligible pregnancies for the final analysis. Flight attendants who worked during early pregnancy had a slightly elevated risk of spontaneous abortion, as compared with attendants who were pregnant outside a time span of active flying (odds ratio [OR] = 1.3; 95% confidence interval [CI], 0.9 to 1.8). During the earliest years of the study period (1973 through 1977), the risk seemed to be decreased (OR = 0.4; 95% CI, 0.2 to 1.1), whereas during the later years (1978 through 1994) the risk was increased (OR = 1.6; 95% CI, 1.1 to 2.4). The results are in agreement with earlier studies, showing suggestive evidence of a slightly increased risk of spontaneous abortion among female cabin crew members.     

Abortion and its effect on risk of preeclampsia and transient hypertension

We examined the effect of abortion type, number, and gestational age on the risk of preeclampsia and transient hypertension among women who received prenatal care from 13 obstetric practices in southern Connecticut between April 1988 and December 1991 (N = 2,739). Subjects were interviewed before 16 weeks' gestation regarding reproductive history and pregnancy-related risk factors. We estimated the risk of preeclampsia (N = 44) and transient hypertension (N = 172) among nulliparous women who had had one or more abortions, with nulliparous women with no abortion as the referent group. Similar effects were seen for one spontaneous or induced abortion, when analyzed separately. A single prior abortion was associated with a decreased risk of preeclampsia [odds ratio (OR) = 0.35; 95% exact confidence interval (CI) = 0.09-1.01]. One abortion had only a small association with risk of transient hypertension (OR = 1.09, 95% exact CI = 0.68-1.72); however, a history of two or more abortions was associated with a decreased risk (OR = 0.42, 95% exact CI = 0.16-0.94). Among nulliparous women with a history of one abortion, a decreased risk of both hypertensive disorders was observed among women whose aborted pregnancy ended at > or =3 months gestation. These findings suggest that a history of abortion in nulliparous women is a protective factor against the risk of preeclampsia in the subsequent pregnancy.     

Induced abortion and low birthweight in the following pregnancy

BACKGROUND: To examine whether induced abortion increases the risk of low birthweight in subsequent singleton live births. METHODS: Cohort study using the Danish Medical Birth Registry (MBR), the Hospital Discharge Registry (HDR), and the Induced Abortion Registry (IAR). All women who had their first pregnancy during 1980-1982 were identified in the MBR, the HDR, and the IAR. We included all 15,727 women whose pregnancy was terminated by a first trimester induced abortion in the induced abortion cohort and 46,026 women whose pregnancy was not terminated by an induced abortion were selected for the control cohort. All subsequent pregnancies until 1994 were identified by register record linkage. RESULTS: Low birthweight (<2500 g) in singleton term live births occurred more frequently in women with one, two, three or more previous induced abortions, compared with women without any previous induced abortion of similar gravidity, 2.2% versus 1.5%, 2.4% versus 1.7%, and 1.8% versus 1.6%, respectively. Adjusting for maternal age and residence at time of pregnancy, interpregnancy interval, gender of newborn, number of previous spontaneous abortions and number of previous low birthweight infants (control cohort only), the odds ratios (OR) of low birthweight in singleton term live births in women with one, two or more previous first trimester induced abortions were 1.9 (95% CI: 1.6, 2.3), and 1.9 (95% CI: 1.3, 2.7), respectively, compared with the control cohort of similar gravidity. High risks were mainly seen in women with an interpregnancy interval of more than 6 months. CONCLUSIONS: The findings suggest a positive association between one or more first trimester induced abortions and the risk of low birthweight in subsequent singleton term live births when the interpregnancy interval is longer than 6 months. This result was unexpected and confounding cannot be ruled out.     

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.     

尿道下裂危险因素的病例对照研究

目的 探讨尿道下裂病因。方法 采用以医院为基础的1:2配比的病例对照研究方法,以统一的调查表及调查方式对107倒尿道下裂及214例对照进行面对面问卷调查,应用SAS 6.12软件对所有调查因素进行单因素及多因素logistic回归分析。结果 胎儿尿道下裂的发生与母亲孕前自然流产史(OR=3.87,95％CI:1.60～9.39)、孕期发生先兆流产(OR=3.57,95％CI:1.31～9.64)、孕早期感冒伴发热(OR=7.63,95％CI:2.50～23.24)、孕中期用抗感染和/或解热止痛药(OR=16.46,95％CI;3.46～78.21)、父亲职业性接触农药(OR=3.70,95％CI:1.49～9.16)及胎儿低出生体重(OR=12.62,95％CI:2.97～53.67)呈正相关,与母亲孕早期增加蛋白质类营养(OR=0.33,95％CI:O.15～0.74)呈负相关。结论 母亲孕前自然流产史、孕期发生先兆流产、孕早期感冒伴发热、孕中期用抗感染和/或解热止痛药、父亲职业性接触农药、胎儿低出生体重等可能增加胎儿发生尿道下裂的危险,而母亲孕早期增加蛋白质类营养可能降低胎儿发生尿道下裂的危险。     

隐睾发生的危险因素研究

目的：研究隐睾发生的危险因素。方法：采用以医院为基础的1：2配比的病例对照研究方法，按统一的调查方法对99例隐睾及198例对照组面对面问卷调查。应用SAS6。12软件对所调查因素进行单因素及多因素logistic回归分析，结果：胎儿隐睾与母亲孕早期感冒伴发热（OR＝9．37，95％CI：2．25－39．09），孕期发生先兆流产（OR＝4．66，95％CI，2．02＝10．74），孕期发生先兆子痫（OR＝16．33，95％CI：1．40－191．20），父亲职业性接触农药（OR＝12．79％CI；2．90－56．43），低出生体重（OR＝5．77，95％CI：1．39－23．98），母亲怀孕年龄＜24（OR＝2．89，95％CI：1．29－4．06）呈正相关。结论：母亲孕早期感冒伴发热，孕期发生先兆流产及先兆子痫，父亲职业性接触农药，低出体重，母亲怀孕年龄＜24岁是隐睾发病的主要危险因素。     

夫妻生活习惯与不良生育史的关系

目的调查西城区育龄妇女不良生育史的发生情况及与夫妻双方生活习惯的关系,为优生优育工作提供依据。方法采用横断面调查,对2005—2009年北京市西城区12191位有生育意愿育龄妇女的不良生育史,夫妻双方生活习惯、危险因素接触及患病情况等进行分析,探讨影响不良生育史发生的因素。结果研究人群的不良生育史发生比例为2．1％,其中自然流产史发生比例为1．6％;妻子挑食,丈夫吸烟、饮酒者自然流产史发生比例高;夫妻至少一方接触毒物,妻子挑食,丈夫饮酒者死胎死产史发生比例高;夫妻至少一方吸烟,丈夫接触毒物者宫外孕史发生比例高,与无上述因素者比较,差异有统计学意义;Logistic回归结果显示,妻子挑食（OR=1．2,95％CI：1．0～1．4）、丈夫吸烟（OR=2．0,95％CI：1．4—2．8）者发生自然流产史的风险高;妻子挑食（OR=1．2,95％CI：1．0—1．4）、丈夫饮酒（OR=2．0,95％CI：1．4～2．8）、丈夫接触毒物（OR=6．3,95％CI：2．3—17．3）者发生不良生育史风险高。结论不良生育史的发生与夫妻生活习惯有关,预防不良生殖结局的发生应将夫妻双方均作为目标人群进行干预。     

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.     

自然流产者绒毛织中维生素A、E含量及流产影响因素分析

目的 了解孕早期妇女的自然流产状况与维生素A、E营养状况的关系,为指导孕妇健康膳食提供科学依据.方法 于2010年10月～2011年4月在广州市收集进行流产刮宫术的孕妇绒毛组织共258例(自然流产组63例,对照组195例).对研究对象进行问卷调查及24h膳食调查,并采用高效液相色谱法检测绒毛组织中的维生素A、E含量.结果 自然流产组与对照组的比较中,年龄、体质指数、婚姻状况、流产史、孕周的差异均具有统计学意义(均有P＜0.05);多因素Logistic回归分析显示,自然流产的危险因素为年龄(与≤22岁相比,23～岁组:OR=3.903,95％CI:1.533～9.937;≥29岁组:OR=2.896,95％CI:1.116 ～7.519)、流产史(OR=2.174,95％ CI:1.105 ～4.278)和孕周≥8周(OR=3.532,95％CI:1.813 ～6.883).自然流产组能量、蛋白质、脂肪、碳水化合物、维生素A、维生素E的摄入量与对照组比较,差异也无统计学意义.自然流产组绒毛组织中维生素A、E含量与对照组的比较,差异均无统计学意义(均有P＞0.05).结论 年龄、流产史是自然流产的危险因素;未见自然流产者膳食维生素A、E摄入量及绒毛组织中维生素A、E含量增加.     

Induced abortion and risk of subsequent miscarriage

BACKGROUND: To evaluate the impact of surgically induced first-trimester abortion on the risk of miscarriage in a subsequent pregnancy. METHODS: The study is a pregnancy cohort study. It was conducted among 15 general hospitals or maternity and infant health institutes in Shanghai, China from November 1993 to March 1998. The abortion cohort consisted of pregnant women whose previous pregnancies were terminated by vacuum aspiration (98%). The reference cohort consisted of primigravidae. Subjects were recruited at 35-63 days of gestational age. A total of 2953 pregnant women were enrolled; 1502 in the abortion cohort, 1451 in the reference cohort. RESULTS: There were only 62 women lost to follow-up. The remaining 2891 women had 2732 live births, and 137 miscarriages. About 5.5% of pregnancies in the abortion cohort were miscarried and 4.0% in the reference cohort. Once potential confounders were controlled for by logistic regression, odds ratio (OR) of miscarriage between the abortion cohort and the reference cohort was 1.55 (95% CI: 1.08-2.23). The adjusted OR were 2.44 (95% CI: 1.16-5.15) among women who were recruited within 49 days of gestational age, and 1.72 (95% CI: 1.09-2.72) for the first-trimester miscarriage. CONCLUSIONS: Induced abortion by vacuum aspiration is associated with an increased risk of first-trimester miscarriage in the subsequent pregnancy.