A meta-analysis of the association between induced abortion and breast cancer risk among Chinese females

Non-genetic factors and breast cancer: an umbrella review of meta-analyses

BACKGROUND

Previous research has found associations between various non-genetic factors and breast cancer (BrCa) risk. This study summarises and appraises the credibility of the available evidence on the association between non-genetic factors and BrCa risk.

METHODS

We conducted an umbrella review of meta-analyses. Medline, Scopus, and the Cochrane databases were systematically searched for meta-analyses examining non-genetic factors and BrCa incidence or mortality. The strength of the evidence was graded in four categories (i.e., weak, suggestive, highly suggestive, convincing).

RESULTS

A total of 781 meta-analyses from 280 publications were evaluated and graded. We included exposures related to anthropometric measurements, biomarkers, breast characteristics and diseases, diet and supplements, environment, exogenous hormones, lifestyle and social factors, medical history, medication, reproductive history, and pregnancy. The largest number of examined associations was found for the category of diet and supplements and for exposures such as aspirin use and active smoking. The statistically significant (P-value < 0.05) meta-analyses were 382 (49%), of which 204 (53.4%) reported factors associated with increased BrCa risk. Most of the statistically significant evidence (n = 224, 58.6%) was graded as weak. Convincing harmful associations with heightened BrCa risk were found for increased body mass index (BMI), BMI and weight gain in postmenopausal women, oral contraceptive use in premenopausal women, increased androstenedione, estradiol, estrone, and testosterone concentrations, high Breast Imaging Reporting and Data System (BIRADS) classification, and increased breast density. Convincing protective factors associated with lower BrCa risk included high fiber intake and high sex hormone binding globulin (SHBG) levels while highly suggestive protective factors included high 25 hydroxy vitamin D [25(OH)D] levels, adherence to healthy lifestyle, and moderate-vigorous physical activity.

CONCLUSIONS

Our findings suggest some highly modifiable factors that protect from BrCa. Interestingly, while diet was the most studied exposure category, the related associations failed to reach higher levels of evidence, indicating the methodological limitations in the field. To improve the validity of these associations, future research should utilise more robust study designs and better exposure assessment techniques. Overall, our study provides knowledge that supports the development of evidence-based BrCa prevention recommendations and guidance, both at an individual level and for public health initiatives.

TRIAL REGISTRATION

PROSPERO CRD42022370675.

Induced abortion and ectopic pregnancy: A systematic review and meta-analysis

OBJECTIVE

Existing evidence of the relationship between induced abortion and ectopic pregnancy has not been assessed rigorously. This systematic review provides a comprehensive evaluation to examine whether induced abortion (IA) can increase the rate of ectopic pregnancy (EP).

METHODS

We searched PubMed, EMBASE, Web of Science, Cochrane, CNKI, WanFang, and Sinomed databases since their inception until February 2023. Eligibility criteria included case-control studies and cohort studies that analyzed induced abortion associated with ectopic pregnancy. Data analyses were conducted by using R-studio Version 1.1.383 software.

RESULTS

A total of 33 case-control studies and 7 cohort studies involving 132,926 participants were included. In case-control studies, there was a significant association between induced abortion and ectopic pregnancy by using single-factor analysis data (OR = 2.32, 95% CI = 1.81-2.98). Subgroup analysis by region suggested no statistical significance in the Americas (OR = 1.15, 95% CI = 0.92-1.43) and Eastern Mediterranean (OR = 3.64, 95% CI = 0.88-15.18). The relationship was significant by using multiple regression analysis data (OR = 1.97, 95% CI = 1.38-2.80). In cohort studies, statistical significance was found (OR = 1.42, 95% CI = 1.001-2.018) after omitting one study in sensitivity analysis. The combined results of the two types of studies suggested that induced abortion would increase the risk of ectopic pregnancy to some degree, but the conclusion needs to be considered with caution.

CONCLUSION

This study indicated that IA could increase the risk of EP to some degree and the times of IA had a negative impact on the risk. Safe abortion and avoiding repeat abortion due to unintended pregnancy could protect women's fertility.

Prevalence and determinants of repeat induced abortion in Ethiopia: A systematic review and meta-analysis

Introduction

Repeat-induced abortion is the termination of pregnancy for more than one time using drugs or surgical intervention before the fetus reaches the age of viability. This study aimed to estimate the pooled prevalence of repeat-induced abortion and its determinants among women in Ethiopia.

Materials and methods

PubMed, HINARI and Google Scholar were systematically searched for eligible studies. A random effect model was used to estimate the pooled prevalence. The Cochrane Q-statistics and I2 tests were used to assess heterogeneity between included studies.

Results

The estimated pooled prevalence of repeat-induced abortion was 30.89% (95% CI: 28.88-32.91). Alcohol consumption (POR = 3.60, 95%CI: 2.26-5.74), assuming the procedure painless (POR = 2.79, 95%CI: 1.77-4.39), no fertility awareness (POR = 3.45, 95% CI: 1.05-11.36), and women with multiple sexual partners (POR = 4.31, 95% CI: 3.36-5.53) were significantly associated with repeat-induced abortion.

Conclusion

The study revealed that about one in ten women who had a history of abortion experienced repeat-induced abortion. Alcohol consumption, no fertility awareness, assuming the procedure is painless, and having multiple sexual partners were significantly associated with repeat-induced abortion.

Genetic and lifestyle factors for breast cancer risk assessment in Southeast China

BACKGROUND

Despite the rising incidence and mortality of breast cancer among women in China, there are currently few predictive models for breast cancer in the Chinese population and with low accuracy. This study aimed to identify major genetic and life-style risk factors in a Chinese population for potential application in risk assessment models.

METHODS

A case-control study in southeast China was conducted including 1321 breast cancer patients and 2045 controls during 2013-2016, in which the data were randomly divided into a training set and a test set on a 7:3 scale. The association between genetic and life-style factors and breast cancer was examined using logistic regression models. Using AUC curves, we also compared the performance of the logistic model to machine learning models, namely LASSO regression model and support vector machine (SVM), and the scores calculated from CKB, Gail and Tyrer-Cuzick models in the test set.

RESULTS

Among all factors considered, the best model was achieved when polygenetic risk score, lifestyle, and reproductive factors were considered jointly in the logistic regression model (AUC = 0.73; 95% CI: 0.70-0.77). The models created in this study performed better than those using scores calculated from the CKB, Gail, and Tyrer-Cuzick models. However, the logistic model and machine learning models did not significantly differ from one another.

CONCLUSION

In summary, we have found genetic and lifestyle risk predictors for breast cancer with moderate discrimination, which might provide reference for breast cancer screening in southeast China. Further population-based studies are needed to validate the model for future applications in personalized breast cancer screening programs.

Abortion and Female Cancer Risks among Women Aged 20 to 45 Years: A 10-Year Longitudinal Population-Based Cohort Study in Taiwan

BACKGROUND

Female cancers, including breast, cervical, uterine, and ovarian cancer, remain among the ten most common cancers among women worldwide, but the relationship between female cancers and abortion from previous studies is inconsistent. This study aimed to investigate risks of incident female cancers among women aged 20 to 45 years who underwent abortion in Taiwan compared with those who did not.

METHOD

A longitudinal observational cohort study was conducted using three nationwide population-based databases in Taiwan, focusing on 20- to 45-year-old women, with 10 years of follow-up. Matched cohorts were identified with propensity score 1-to-3 matching between 269,050 women who underwent abortion and 807,150 who did not. Multivariable Cox proportional hazard modeling was used for analysis after adjusting for covariates including age, average monthly payroll, fertility, diabetes mellitus, polycystic ovarian syndrome, endometrial hyperplasia, endometriosis, hormone-related drugs, and Charlson comorbidity index.

RESULTS

We found lower risk of uterine cancer (hazard ratio [HR]: 0.77, 95% CI: 0.70-0.85) and ovarian cancer (HR: 0.81, 95% CI: 0.75-0.88), but no significant difference in risk of breast cancer or cervical cancer, among matched abortion compared with non-abortion cohorts. Regarding subgroup analysis, cervical cancer risk was higher for parous women who underwent abortion, and uterine cancer risk was lower for nulliparous women who underwent abortion compared with non-abortion groups.

CONCLUSIONS

Abortion was related to lower uterine and ovarian cancer risk but was not associated with risks of incident breast cancer or cervical cancer. Longer follow-up may be necessary to observe risks of female cancers at older ages.

Epidemiology beyond its limits

In 1995, journalist Gary Taubes published an article in Science titled "Epidemiology faces its limits," which questioned the utility of nonrandomized epidemiologic research and has since been cited more than 1000 times. He highlighted numerous examples of research topics he viewed as having questionable merit. Studies have since accumulated for these associations. We systematically evaluated current evidence of 53 example associations discussed in the article. Approximately one-quarter of those presented as doubtful are now widely viewed as causal based on current evaluations of the public health consensus. They include associations between alcohol consumption and breast cancer, residential radon exposure and lung cancer, and the use of tanning devices and melanoma. This history should inform current debates about the reproducibility of epidemiologic research results.

Prevalence of stress and depression and associated factors among women seeking a first-trimester induced abortion in China: a cross-sectional study

OBJECTIVES

To determine the prevalence of stress and depression and associated factors among women seeking a first-trimester induced abortion in China.

METHODS

A cross-sectional study was conducted in a tertiary hospital in Beijing, from April 1st to Oct 31st, 2021. Women seeking termination of an intrauterine first-trimester pregnancy were invited to participate and complete a digital self-administered questionnaire. The survey included socio-demographic and health questions, Perceived Stress Scale-10 (PSS-10), and Patient Health Questionnaire-9 (PHQ-9). Descriptive analyses and binary logistic regression analyses were performed using SPSS 23.0.

RESULTS

A total of 253 women participated. Prevalence of high perceived stress (cut-off ≥ 20) and depressive symptoms (cut-off ≥ 10) was 25.3% and 22.5%, respectively. Women were more likely to suffer high stress if they reported low resilience (aOR = 16.84, 95% CI 5.18-54.79), were not-using contraceptives (aOR = 3.27, 95% CI 1.39-6.29), had low social support (aOR = 2.95, 95% CI 1.39-6.29), were non-local residents (aOR = 2.51, 95% CI 1.15-5.92), were dissatisfied with their intimate relationship (aOR = 2.44, 95% CI 1.15-5.16), or held pro-life attitudes towards abortion (aOR = 1.04, 95% CI 1.18-3.53). Odds of experiencing depression were higher among women who also reported high perceived stress (aOR = 19.00, 95% CI 7.67-47.09), had completed higher education (aOR = 12.28, 95% CI 1.24-121.20), and were non-local residents (aOR = 3.38, 95% CI 1.37-8.32).

CONCLUSIONS

The magnitude of perceived stress and depression was high among Chinese women seeking a first-trimester induced abortion. It is necessary to comprehensively evaluate the mental health of women seeking an abortion, especially those with high risk. Interventions to mitigate relevant associated factors could improve the psychological wellbeing of women.

A Meta-Analysis of Induced Abortion, Alcohol Consumption, and Smoking Triggering Breast Cancer Risk among Women from Developed and Least Developed Countries

BACKGROUND

The most prominent form of cancer in women is breast cancer, and modifiable lifestyle risk factors, including smoking, alcohol consumption, and induced abortion, can all contribute significantly to this disease.

OBJECTIVES

This study's primary purpose was to assess the prevalence of breast cancer among women in developed and developing countries and the association between three modifiable hazard factors (induced abortion, smoking behavior, and alcohol use) and breast cancer.

METHODS

This study performed a systematic literature database review up to September 21, 2021. We employed meta-analytic tools such as the random effects model, forest plot, and subgroup analysis to conduct the research. Additionally, we conducted a sensitivity analysis to assess the influence of outliers.

RESULTS

According to the random effects model, smoker women have a higher risk of developing breast cancer from different countries (OR = 1.46; 95% CI: 1.08-1.97). In the case of induced abortion, the pooled estimate (OR = 1.25; 95% CI: 1.01-1.53) indicated a significant link between abortion and breast cancer. Subgroup analysis revealed that smoking substantially influences breast cancer in developing and developed countries. Breast cancer was more common among women who smoked in developed countries than in developing nations.

CONCLUSION

The observed findings give sufficient support for the hypothesis that smoking and abortion have a significant influence on breast cancer in different nations. Health organizations should individually design comprehensive scientific plans to raise awareness about the risks of abortion and smoking in developed and developing countries.

Breast cancer risk factors in Iran: a systematic review & meta-analysis

OBJECTIVES

Breast cancer is known as one of the deadliest forms of cancer, and it is increasing globally. There are a variety of proven and controversial risk factors for this malignancy. Herein, we aimed to undertake a systematic review and meta-analysis focus on the epidemiology of breast cancer risk factors in Iran.

METHODS

We performed a systematic search via PubMed, Scopus, Web of Science, and Persian databases for identifying studies published on breast cancer risk factors up to March 2019. Meta-analyses were done for risk factors reported in more than one study. We calculated odds ratios (ORs) with corresponding 95% confidence intervals (CIs) using a fixed/random-effects models.

RESULTS

Thirty-nine studies entered into the meta-analysis. Pooling of ORs showed a significant harmful effect for risk factors including family history (OR: 1.80, 95%CI 1.47-2.12), hormonal replacement therapy (HRT) (OR: 5.48, 95%CI 0.84-1.74), passive smokers (OR: 1.68, 95%CI 1.34-2.03), full-term pregnancy at age 30 (OR: 3.41, 95%CI 1.19-5.63), abortion (OR: 1.84, 95%CI 1.35-2.33), sweets consumption (OR: 1.71, 95%CI 1.32-2.11) and genotype Arg/Arg (crude OR: 1.59, 95%CI 1.07-2.10), whereas a significant protective effect for late menarche (OR: 0.58, 95%CI 0.32-0.83), nulliparity (OR: 0.68, 95%CI 0.39-0.96), 13-24 months of breastfeeding (OR: 0.68, 95%CI 0.46-0.90), daily exercise (OR: 0.59, 95%CI 0.44-0.73) and vegetable consumption (crude OR: 0.28, 95%CI 0.10-0.46).

CONCLUSIONS

This study suggests that factors such as family history, HRT, passive smokers, late full-term pregnancy, abortion, sweets consumption and genotype Arg/Arg might increase risk of breast cancer development, whereas late menarche, nulliparity, 13-24 months breastfeeding, daily exercise and vegetable consumption had an inverse association with breast cancer development.

Expression and clinicopathological significance of AOC4P, PRNCR1, and PCAT1 lncRNAs in breast cancer

Long none coding RNAs (lncRNAs) AOC4P, PRNCR1, and PCAT-1 are dysregulated in various types of malignancies. However, their expression and clinicopathological significances are uncertain in breast cancer (BC). Quantitative real-time polymerase chain reaction (RT- qPCR) was used to measure the expression levels of the selected lncRNAs in tumor tissues obtained from 50 BC patients compared to the normal adjacent tissues (NATs) and 50 clinically healthy normal tissues. Our results revealed a significant downregulation of AOC4P, however, upregulated PRNCR1 and PCAT1 were found in tumor tissues compared to NATs and clinically healthy normal tissues (P < 0.05). Interestingly, remarkable decreased expression of AOC4P was observed in NATs than clinically healthy normal tissues. Dysregulation of the lncRNAs was correlated with worse outcomes of patients. Furthermore, our data showed that the altered expression levels of lncRNAs AOC4P, PRNCR1, and PCAT1 might be occurred through the function of demographic and reproductive variables. Taken together, the altered regulation of AOC4P, PRNCR1, and PCAT1 may highlight their crucial roles in BC development and pathogenesis. Our findings also proposed demographic and reproductive variables as risk factors in BC through the possible influence on the expression of the studied lncRNAs. Nevertheless, further explorations are required to elucidate the more detailed functions of these lncRNAs in BC.

Risk factors of breast intraductal lesions in patients without pathological nipple discharge

The majority of breast cancer arises from the ductal epithelium. It is crucial in the diagnosis and treatment of breast cancer by detecting intraductal lesions at an early stage. The typical clinical characteristic of intraductal lesions is pathological nipple discharge (PND), although many patients with intraductal lesions do not exhibit PND. It is a serious challenge for clinicians to detect patients with intraductal lesions without PND at an early stage. The aim of the present study was to investigate the risk factors associated with intraductal lesions in patients without PND. This retrospective database review, conducted between April 2016 and April 2017, included 370 lesions from 255 patients with intraductal lesions (intraductal papilloma, atypical intraductal hyperplasia, intraductal carcinoma in situ) and non-intraductal lesions (fibroadenoma, adenosis, cysts, lobular carcinoma in situ), diagnosed through surgical pathology. The patients were divided into two groups based on pathological diagnosis and clinical parameters were evaluated using univariate and multivariate analyses. Univariate analysis revealed that 9 of 14 factors were statistically significant. Five factors were identified to be associated risk factors in patients without PND through the multivariate logistic regression analysis: Age between 35 and 49 years and age ≥50 years [odds ratio (OR)=4.749, 95% confidence interval (CI)=2.371-9.513, P<0.001; OR=2.587, 95% CI=2.587-14.891, P<0.001; respectively], non-menstrual breast pain (OR=1.922, 95% CI=1.037-3.564, P=0.038), breast duct dilatation as seen using ultrasonography (OR=9.455, 95% CI=3.194-27.987, P<0.001), lesion distance from nipple ≤2 cm (OR=2.747, 95% CI=1.668-4.526, P<0.001) and lesion size ≤1 cm (OR=1.903, 95% CI=1.155-3.136, P=0.012). In conclusion, for patients without PND but with risk factors, such as the patient being >35 years, with non-menstrual breast pain, breast duct ectasia, lesion distance from nipple ≤2 cm and lesion size ≤1 cm as seen using ultrasonography, clinicians should be highly concerned about the possibility of intraductal lesions, in order to prevent misdiagnosis and reduce the misdiagnosis rate.

No association between abortion and risk of breast cancer among nulliparous women: Evidence from a meta-analysis

BACKGROUND

Various epidemiological studies have demonstrated the association between abortion and risk of breast cancer among nulliparous women; however, results remain inconclusive. This meta-analysis assessed the association based on previous studies.

METHODS

PubMed, EMBase, China National Knowledge Infrastructure, Chongqing VIP, and Wanfang databases were searched for relevant articles until February 2018. In this meta-analysis, fixed-effects models were used to estimate the combined effect size and the corresponding 95% confidence interval (CI). All statistical data were analyzed using STATA 12.0.

RESULTS

A total of 14 articles consisting of 6 cohort studies and 8 case-control studies were included in this review. All articles were of high quality, as determined based on the Newcastle Ottawa Scale assessment. The combined risk ratio (RR) indicated no significant association between abortion and breast cancer among nulliparous women (RR = 1.023, 95%CI = 0.938-1.117; Z = 0.51, P = .607). Subgroup analyses revealed no significant associations between risk of breast cancer and induced abortion or between risk of breast cancer and spontaneous abortion (SA) among nulliparous women (RR = 1.008, 95% CI = 0.909-1.118 and RR = 1.062, 95%CI = 0.902-1.250, respectively). Neither 1 nor >2 abortions increased the risk of breast cancer among nulliparous women. Sensitivity analysis showed that our results were reliable and stable.

CONCLUSION

Current evidence based on epidemiological studies showed no association between abortion and risk of breast cancer among nulliparous women.

Clinical and epidemiologic factors associated with breast cancer and its subtypes among Northeast Chinese women

The incidence of breast cancer has increased dramatically in China. We evaluated the clinical and epidemiologic factors associated with breast cancer, and its stage in a case‐control study of Northeast Chinese women. We also examined whether these factors were differentially distributed among molecular subtypes of breast cancer in a case‐only analysis. We identified 1118 breast cancer patients and 2284 healthy women from Cancer Hospital of Medical University between January 2014 and December 2017. Logistic regression models were used to calculate the odds ratios (ORs) and corresponding 95% confidence intervals (CIs). We found that postmenopausal women had a decreased risk of breast cancer (multivariate‐adjusted OR = 0.33, 95% CI:0.25‐0.43), and tended to have breast cancer of human epidermal growth factor receptor 2 (HER2)‐overexpressing (multivariate‐adjusted OR = 2.99, 95% CI: 1.49‐5.97) and triple‐negative (multivariate‐adjusted OR = 2.16, 95% CI: 1.02‐4.56) subtypes, compared with the luminal B subtype. Women with history of abortion had an increased risk of breast cancer (multivariate‐adjusted OR = 4.70, 95% CI: 3.60‐6.14). Women with high breast density and high Breast Imaging Reporting and Data System (BIRADS) scores of lesions tended to have breast cancer of advanced stage, but were not differentially distributed among its molecular subtypes. In conclusion, postmenopausal women had decreased risk of breast cancer, and tended to have nonluminal subtype, while women with history of abortion had increased risk of breast cancer. Women with high breast density and BIRADS scores of lesions tended to have advanced stage breast cancer. We provide evidence on the epidemiologic factors for breast cancer and its subtypes, which may help with breast cancer risk stratification.

Biological, Behavioral and Physiological Consequences of Drug-Induced Pregnancy Termination at First-Trimester Human Equivalent in an Animal Model

Given the significant physiological changes that take place during and resulting from pregnancy, as well as the relative absence of such information in relation to pregnancy termination, this study investigated the potential for developing a valid animal model to objectively assess the biological, physiological and behavioral consequences of drug-induced pregnancy termination. Female Long-Evans rats were divided into four groups (n = 19-21/group), controlling for drug [mifepristone (50 mg/kg/3 ml, i.g.)/misoprostol (0.3 mg/kg/ml, i.g.) or vehicle (1% Carboxymethylcellulose Sodium/0.2% Tween® 80 suspension, i.g.)] and pregnancy. Drug administration took place on days 12-14 of gestation (days 28-40 human gestational equivalent). Vehicle was administered to the controls on the same days. Parameters measured included rat body weight, food intake, vaginal impedance, sucrose consumption/preference, locomotor activity, forced swim test, and home-cage activity. At the termination of the study, rats were deeply anesthetized using urethane, and blood, brain, and liver were collected for biochemical analysis. Following drug/vehicle administration, only the pregnancy termination group (pregnant, drug) displayed a significant decrease in body weight, food intake, locomotor activity-related behaviors and home-cage activity relative to the control group (non-pregnant, vehicle). Additionally, the pregnancy termination group was the only group that displayed a significant reduction in sucrose consumption/preference during Treatment Week relative to Pre-Treatment Week. Vaginal impedance did not significantly decrease over time in parous rats in contrast to all other groups, including the rats in the pregnancy termination group. Biochemical analysis indicated putative drug- and pregnancy-specific influences on oxidative balance. Regression analysis indicated that pregnancy termination was a predictor variable for body weight, food intake and all locomotor activity parameters measured. Moreover, pertaining to body weight and food intake, the pregnancy termination group displayed significant changes, which were not present in a group of naturally miscarrying rats following pregnancy loss. Overall, our results appear to suggest negative biological and behavioral effects following pregnancy termination, that appear to also be distinct from natural miscarriage, and potential benefits of parity pertaining to fecundity. Thus, our findings indicate the importance for further objective investigation of the physiological and behavioral consequences of medical abortion, in order to provide further insight into the potential implications in humans.

Induced Abortion, Birth Control Methods, and Breast Cancer Risk: A Case-Control Study in China

Background

The association between induced abortion and birth control methods (including oral contraceptives and intrauterine devices) and breast cancer may vary among countries, due to the different usage and frequency of birth control methods and induced abortion among countries. A better understanding of this association may help in determining safer birth control methods for Chinese women.

Methods

A case-control study was conducted with a total of 794 cases and 805 controls. Standardized questionnaires were used to collect information on demographic characteristics, exposure to induced abortion, birth control methods, and other risk factors for breast cancer. Multivariate logistic regression was conducted to explore the association between birth control methods and breast cancer.

Results

Multivariate logistic regression analyses showed that having a history of medical abortions, ≥3 surgical abortions, or both medical and surgical abortions was associated with an increased risk of breast cancer in post-menopausal women (odds ratio [OR] 2.48; 95% confidence interval [CI], 1.14–5.40). Pre-menopausal women who had used intra-uterine devices (IUDs) for more than 20 years tended to have a lower breast cancer risk than other age-matched pre-menopausal women (OR 0.41; 95% CI, 0.25–0.68). Both pre-menopausal and post-menopausal women who had <20 years exposure to IUDs and those who had used two or more birth control methods (with the exception of women who used IUDs for more than 20 years) tended to have much higher breast cancer risk.

Conclusion

The relationship between induced abortion and birth control methods and breast cancer was complex, though being exposed to induced abortion and two or more birth control methods in one’s lifetime appeared to be risk factors for breast cancer in Chinese women.

Association of induced abortion with preterm birth risk in first-time mothers

Women who have previously had an induced abortion (IA) before their first birth have been associated with preterm birth (PTB). However, previous studies on the PTB are inconsistent. Therefore, the aim of this study was to clarify the association between IA and PTB and low birth weight (LBW) for first-time mothers. A total of 3,684 Southern Chinese women who gave birth for the first time to a live singleton infants were recruited between January 2015 and December 2015 in the province of Guangdong, China. Univariable and multivariable analyses were conducted to determine whether IA was associated with PTB and LBW. Previous IA was not associated with increased risks of PTB or LBW, adjusted odds ratios were 0.80 (95% CI = 0.53 to 1.20) and 0.86 (95% CI = 0.57 to 1.31), respectively. Additionally, no significant associations were observed for infants born at before 37, before 32, and before 28 gestational weeks. And no significant associations were also observed for LBW measuring lower than 2500 grams and also measuring lower than 1500 grams. Our study suggested that a previous IA, as compared with women who reported no previous IA, does not increase the risk of PTB or LBW in subsequent pregnancy for the first-time mothers among Southern Chinese women.

Menstrual and reproductive factors and risk of breast cancer: A case-control study in the Fez region, Morocco

BACKGROUND

Breast cancer is the most common cancer in women worldwide. In the Moroccan context, the role of well-known reproductive factors in breast cancer remains poorly documented. The aim of this study was to explore the relationship between menstrual and reproductive factors and breast cancer risk in Moroccan women in the Fez region.

METHODS

A case-control study was conducted at the Hassan II University Hospital of Fez between January 2014 and April 2015. A total of 237 cases of breast cancer and 237 age-matched controls were included. Information on sociodemographic characteristics, menstrual and reproductive history, family history of breast cancer, and lifestyle factors was obtained through a structured questionnaire. Conditional logistic regression models were used to estimate odds ratios and 95% confidence intervals for breast cancer by menstrual and reproductive factors adjusted for potential confounders.

RESULTS

Early menarche (OR = 1.60, 95% CI: 1.08-2.38) and nulliparity (OR = 3.77, 95% CI: 1.98-7.30) were significantly related to an increased risk of breast cancer, whereas an early age at first full-term pregnancy was associated with a decreased risk of breast cancer (OR = 0.41, 95% CI: 0.25-0.65).

CONCLUSION

The results of this study confirm the role of established reproductive factors for breast cancer in Moroccan women. It identified some susceptible groups at high risk of breast cancer. Preventive interventions and screening should focus on these groups as a priority. These results should be confirmed in a larger, multicenter study.

Induced abortion and breast cancer: An updated meta-analysis

Different epidemiological studies have indicated conflicting information about the association of induced abortion (IA) with breast cancer risk. A recent meta-analysis with prospective evidences did not support the positive association between IA and breast cancer risk. Thus, we in our meta-analysis study have tried to analyze this specific association.We searched all relevant articles from an English-language literature using Pubmed, Embase, and Cochrane databases, until December 10, 2016. All the statistical analyses were performed on case-control studies, using Review Manager Software 5.3 (Cochrane Collaboration, Oxford, UK).Our meta-analysis results based on 25 studies, including 5 studies with Chinese patients, indicated that there was no association of IA with breast cancer (OR = 1.08, 95% CI 0.98-1.19, P = .1). However, significant heterogeneity was observed, and thus further subgroup analyses were conducted. The combined OR of subjects with only 1-time IA was 1.03, 95% CI 0.90 to 1.18, P = .63, while for subjects with 2 or more IAs, it was 1.06, 95% CI 0.86 to 1.30, P = .58. In addition, the ORs of subjects, with 1st IA age either less than 30 or older than 30, were 1.05, 95% CI 0.88 to 1.26, P = .59, and 1.18, 95% CI 0.93 to 1.49, P = .17, respectively. These observations indicated that number of IAs and the age of 1st IA were not associated with breast cancer risk. Due to lack of dose-response relationships, it is difficult to say if number of IAs contributed into statistical heterogeneity. But after subgroup analysis, the age at the 1st IA appeared to impact the statistical heterogeneity. The different reproductive history appears to account for the high heterogeneity among individual studies. Also analysis of nulliparous women showed no significant difference in the association of IA and breast cancer (OR = 1.02, 95% CI 0.86-1.21, P = .85). However, parous women had higher IA rate in case group than control group (OR = 1.11, 95% CI 1.02-1.20, P = .01). Ethnicities might also result in high heterogeneity; thus, we conducted subgroup analyses on Chinese subjects, importantly, with 5 studies having Chinese patients, and did not observe any difference in the incidence of IA and its association with breast cancer between case and control groups (OR = 1.05, 95% CI 0.97-1.13, P = .21).After subgroup analysis, our study showed that IA might increase the risk of breast cancer in parous women, but in the nulliparous, IA was not significantly associated with an increased risk of breast cancer.

Induced Abortion among Chinese Women with Living Child-A National Study

Objective

Induced abortion is widely practiced in China. However, the information on induced abortion is limited. A national cross-sectional survey was designed to determine the risk factors of induced abortion among Chinese women with one child.

Methods

We sampled 16,881 Chinese women with one living child for the study. A structured questionnaire was used to collect induced abortion and related health information. The National Research Institute for Family Planning of China conducted a cross-sectional study among women who had delivered a baby between 2006 and 2008. Information was collected in relation to demographic characteristics (age, ethnicity, region, area etc.), social economic status (education level and occupation), marriage, and the attitude towards potential child’s gender. Multi-logistic regression was used to test potential predictors for conducting abortion stratified by consistency between gender preference and current infants’ gender, and indicating adjusted estimation on selected models of risk factors for abortion.

Results

The mean age of participants was 27.96 ± 4.10 years (median 27 years). Among those women, the prevalence of induced abortion was 8.13 %. In the final model, females living in rural areas (OR = 1.21, 95 %CI: 1.04–1.39), individuals ages 18–25 (OR = 0.84, 95% CI: 0.72–0.99), individuals ages 30 or older (OR = 1.63, 95% CI: 1.42–1.86), and single individuals (OR = 1.72, 95% CI: 1.05–2.83) were more likely to experience induced abortion. Wife gender preference (OR = 0.66, 95 %CI: 0.53–0.83), husband gender preference (Boy: OR = 1.33, 95 %CI: 1.10–1.63; Girl: OR = 1.5, 95% CI: 1.22–1.86), and the area where the individuals were located were significantly associated with the reporting of induced abortion.

Conclusion

The prevalence of induced abortion is high among married women with child in China. There are also socio-demographic characteristics associated with induced abortion in China.

Improved Performance of Adjunctive Ultrasonography After Mammography Screening for Breast Cancer Among Chinese Females

INTRODUCTION

Until now, no studies have investigated whether women other than those with dense breasts are suitable for adjunctive ultrasonography after negative mammography, and investigated whether all women with negative mammography are suitable for adjunctive ultrasonography.

METHODS

Based on the Multi-modality Independent Screening Trial in China, a total of 31,918 women aged 45 to 65 years underwent both ultrasonography and mammography. Physicians performed ultrasonography and mammography separately and were blinded to each other's findings until their interpretations had been recorded. For both ultrasonography and mammography, suspicious results and those highly suggestive of a malignancy were confirmed by pathologic examination, whereas other results were confirmed by 1-year follow-up after initial screening.

RESULTS

Based on Breast Imaging Reporting and Data System (BIRADS) assessments, 84 (84.8%) of 99 cancers were identified on mammography (detection rate, 2.6/1000), and 61 (61.6%) of 99 cancers were identified on ultrasonography (detection rate, 1.9/1000). Integrated mammography with ultrasonography identified 94 (95.0%) of 99 cancers, with an increment of 11.9% in cancer detection rate (from 2.6/1000 to 2.9/1000) (P < .05). Moreover, among women with BIRADS 3, adjunctive ultrasonography detected no cancers. All 10 additional cancers detected by adjunctive ultrasonography were from women with BIRADS 0 to 2, at a cost of 207 women with false positives. Additionally, dense breasts and benign breast disease were significantly associated with positive ultrasonography after BIRADS 0 to 2 (all P values < .05).

CONCLUSIONS

After negative mammography, adjunctive ultrasonography should only be recommended for BIRADS 0 to 2 but not BIRADS 3, especially for women with dense breasts or benign breast disease.

Breast cancer in Mongolia: an increasingly important health policy issue

Breast cancer is a leading cause of cancer-related death for women in both developed and developing countries. The incidence and mortality of breast cancer in Mongolia, while low compared with other counties, has been increasing on an annual basis. In addition, in Mongolia, approximately 90% of the patients are diagnosed at a late stage, resulting in high mortality, with the majority of individuals diagnosed with breast cancer dying within 5 years of diagnosis. Breast cancer screening plays an important role in reducing mortality in Western countries and has been adopted by a number of Asian countries; however, no such approach exists in Mongolia. In a country of limited resources, implementation of expensive health strategies such as screening requires effective allocations of resources and the identification of the most effective imaging methods. This requirement relies on recent accurate data; however, at this time, there is a paucity of information around breast cancer in Mongolia. Until data around features of the disease are available, effective strategies to diagnose breast cancer that recognize the economic climate in Mongolia cannot be implemented and the impact of breast cancer is likely to increase.

Understanding rural-urban differences in risk factors for breast cancer in an Indian population

PURPOSE

Although cancer registry data indicate that there are large differences in breast cancer (BC) rates between rural and urban regions of India, the reasons for these differences are not well understood.

METHODS

We conducted a hospital based case-control study (1,637 breast cancer cases; 1,515 visitor controls) in Mumbai, India, during the years 2009-2013. Extensive questionnaire data, anthropometry measurement and blood samples were collected on all participants. Using logistic regression models, we estimated risk based on odds ratio (OR) and 95 % confidence intervals (CI) for various reproductive and anthropometric measures, stratified by rural-urban status depending upon residence in first 20 years of life.

RESULTS

Waist-to-hip ratio of ≥0.95 compared to ratio ≤0.84 was strongly associated with risk of BC in both rural and urban populations (ORurban = 4.10, 95 % CI 3.03-5.56; ORrural = 3.01, 95 % CI 1.85-4.90). First full-term pregnancy after the age of 25 compared to first full-term pregnancy below 20 years of age was associated with risk of BC in both urban and rural women (ORurban = 1.78, 95 % CI 1.32-2.41; ORrural = 2.24, 95 % CI 1.13-4.43). The prevalence of age at first full-term pregnancy was significantly lower in rural (mean age at first full-term pregnancy = 19.39 years) versus urban women (mean age at first full-term pregnancy = 22.62 years), whereas mean waist circumference was much higher in urban women (82.13 cm) compared to rural women (79.26 cm). We did not observe any association between breast feeding and risk of BC.

CONCLUSIONS

Differences in the prevalence of central adiposity and age at first full-term pregnancy between rural and urban women from India may explain some differences in breast cancer rates between these two populations.

The α-tocopherol derivative ESeroS-GS induces cell death and inhibits cell motility of breast cancer cells through the regulation of energy metabolism

Cancer cells are known to exhibit different hallmarks compared with normal cells. Therefore, targeting these features may improve the response to cancer therapy. In this study, we provided direct evidence that the α-tocopherol derivative ESeroS-GS inhibited the viability, migration, and invasion of breast cancer cells. ESeroS-GS induced cell death in different cancer cells in a dose-dependent manner but showed no significant effects on MCF-10A mammary epithelial cells. Although the ESeroS-GS-induced cell death in MDA-MB-231 breast cancer cells was accompanied with the generation of reactive oxygen species and the down regulation of mitochondrial membrane potential (MMP), no such effect on reactive oxygen species and MMP was seen in MCF-10A cells. Further studies indicated that ESeroS-GS down-regulated the expression of hexokinase II, SDH B, UQCRC2 and COX II in MDA-MB-231 cells but not in MCF-10A cells. The down-regulation of these enzymes accounts for the decreased oxidative phosphorylation (OXPHOS) and glycolysis in MDA-MB-231 cells upon ESeroS-GS treatment. We also found that sub-toxic concentration of ESeroS-GS treatment resulted in the impairment of F-actin cytoskeleton assembly and the consequently decreased migratory and invasive ability of MDA-MB-231 cells, which might be due to the inhibition of cellular energy metabolism. These results indicate that ESeroS-GS shows potential to become a novel anti-cancer agent by targeting the energy metabolism of cancer cells.

Development of a risk assessment tool for projecting individualized probabilities of developing breast cancer for Chinese women

The optimal approach regarding breast cancer screening for Chinese women is unclear due to the relative low incidence rate. A risk assessment tool may be useful for selection of high-risk subsets of population for mammography screening in low-incidence and resource-limited developing country. The odd ratios for six main risk factors of breast cancer were pooled by review manager after a systematic research of literature. Health risk appraisal (HRA) model was developed to predict an individual's risk of developing breast cancer in the next 5 years from current age. The performance of this HRA model was assessed based on a first-round screening database. Estimated risk of breast cancer increased with age. Increases in the 5-year risk of developing breast cancer were found with the existence of any of included risk factors. When individuals who had risk above median risk (3.3‰) were selected from the validation database, the sensitivity is 60.0% and the specificity is 47.8%. The unweighted area under the curve (AUC) was 0.64 (95% CI = 0.50-0.78). The risk-prediction model reported in this article is based on a combination of risk factors and shows good overall predictive power, but it is still weak at predicting which particular women will develop the disease. It would be very helpful for the improvement of a current model if more population-based prospective follow-up studies were used for the validation.

The breast cancer epidemic: 10 facts

Breast cancer, affecting one in eight American women, is a modern epidemic. The increasing frequency of breast cancer is widely recognized. However, the wealth of compelling epidemiological data on its prevention is generally not available, and as a consequence, is largely unknown to the public. The purpose of this report is to review the epidemiological evidence of preventable causes of breast cancer. [Table: see text].