Mental health consequences of military sexual trauma: results from a national survey in the French military.

BACKGROUND: Military sexual trauma (MST) is a major public health concern, given its prevalence and mental health sequelae. This phenomenon is particularly prevalent among women in the US military, although more cases involve men given their overrepresentation. Little is known about MST and its consequences in other military settings, including in Europe. METHODS: This study draws from a national survey in the French military, including 1268 servicemen and 232 servicewomen. We conducted bivariate and multivariate analysis, using simple and multinomial logistic regressions to evaluate the associations between different forms of MST (repeated sexual comments alone/one form of sexual oppression (coercion, repeated verbal unwanted attention or assault)/ several sexual stressors) and symptoms of depression and of positive post-traumatic stress disorder (PTSD) screening scores. RESULTS: Women were both more likely to experience MST and to experience more severe forms of MST than men. Women were also more likely than men to report mental health symptoms (31% versus 18% for symptoms of depression and 4.0% versus 1.8% for positive PTSD screening scores). Different forms of MST were associated with different levels of psychological distress. Women reporting repeated sexual comments alone had higher odds of depressive symptoms (OR=3.1 [1.7, 5.5]) relative to women with no MST. Likewise, the odds of depressive symptoms were 6.5 times higher among women and 8.0 times higher among men who experienced several sexual stressors relative to those who reported no MST. We also found higher relative risk of subthreshold PTSD screening scores among women reporting any form of sexual stressor, including sexual comments alone (RRR = 4.5 [2.8, 7.4]) and an elevenfold increase in the relative risk of positive PTSD screen scores (RRR = 11.3 [2.3, 55.6]) among women who experienced several sexual stressors relative to women with no MST. CONCLUSION: MST is associated with mental health distress among service members in the French military, especially for women. The heightened risk of MST coupled with psychological sequelae call for preventive programs to reduce MST and for screening programs to provide adequate psychological support.

From sexual harassment to sexual assault: Prevalence and correlates of sexual trauma in the French military.

BACKGROUND: Sexual harassment (SH) is prevalent in military settings and dependent on the workplace environment. Few studies have investigated this issue in non-US military settings nor have examined how contextual and individual factors related to Military Sexual Trauma (MST) vary by gender. METHODS: This study draws on a national sexual survey in the French military including 1268 servicemen and 232 servicewomen. We examined four sexual stressors (repeated sexual comments, sexual coercion, repeated unwanted verbal sexual attention and sexual assault (SA)) and two combined measures of verbal SH (comments, unwanted attention) and MST (all forms). We conducted multivariate logistic regressions to identify contextual and individual factors related to these outcomes. RESULTS: 36.7% of women and 17.5% of men experienced MST in the last year and 12.6% and 3.5% reported SA. Factors associated with verbal SH differed from those related to SA. The odds of verbal SH were elevated among men who had sex with men (OR = 3.5) and among women officers (OR = 4.6) while the odds of SA were elevated among men less than 25 years (OR = 3.5) and women with less than a high school diploma (OR = 10.9). The odds of SH increased by 20% to 80% when men worked in units with higher female representation, higher prevalence of MST (sexual comments, or sexual assault, coercion, repeated unwanted attention) and lower acceptance of women in the miliatry. The odds of SA also increased by 70% among men working in units with higher female representation and higher prevalence of sexual oppression. The odds of SA against women were particular high (OR = 5.7) in units with a high prevalence of sexual assault, coercion, or repeated unwanted attention. CONCLUSION: MST is common in the French military, with women experiencing more severe forms than men. Our resuls call for programmatic action to reduce workplace factors related to verbal SH and SA in the French military.

Sexual health in the French military: a multidimensional and gendered perspective.

BACKGROUND: Sexual health in the military comprises a range of concerns including sexually transmitted infections (STI), unintended pregnancy, sexual violence and sexual dysfunction. This study aims to estimate the prevalence of sexual health concerns by gender in the French military and compare these prevalences to estimates in the general population. METHODS: COSEMIL, the first sexual health survey in the French military comprises a probability sample of 1500 military personnel. Chi-square tests were used to compare lifetime abortion, STIs and sexual assault, and recent sexual dysfunction and sexual satisfaction by gender and explore the association between these indicators and current sexual risk (condom use at last intercourse). RESULTS: Women were more likely than men to declare negative sexual health outcomes, with the greatest difference related to sexual assault (24.3% versus 5.1% of males, p < 0.001) and sexual dysfunction hindering sexuality (15.2% of females versus 5.3% of males, p < 0.001). Women were also twice as likely to report ever having an STI (6.7% versus 3.4%, p = 0.03). Comparison with the French general population indicates lower percentages of STIs among military men (2.9% versus 4.9%) and higher percentages of abortion (17.6% versus 14.3%) forced sex (10.6% versus 7.4%) and sexual dysfunction (14.2% versus 9.3%) among military women. CONCLUSION: These results highlight gendered pattern of sexual health in the French military with women suffering greater sexual risks than men. Military health services should include women's health services to address the sexual and reproductive health gender gap.

Prevalence and risk factors of sexually transmitted infections among French service members.

INTRODUCTION: Sexually Transmitted Infections (STIs) have always represented a public health concern in the military, yet most studies rely on self-reports among non-random samples of military populations. In addition, most of the studies exploring STI rates among the military focus on US service members. This paper assesses the prevalence and correlates of STIs in the French military using biomarkers and compares self-reported versus diagnosed STIs. METHODS: Data are drawn from the COSEMIL study, a national sexual health survey conducted in the French military in 2014 and 2015. A random sample of 784 men and 141 women aged 18-57 years completed a self-administered questionnaire and provided biological samples for STI testing. We used logistic regression modeling to identify the correlates of STI diagnosis and self-reports. RESULTS: The prevalence of diagnosed STIs was 4.7% [3.8-5.9], mostly due to Chlamydia trachomatis. This rate was four times higher than the 12 months self-reported rate of 1.1% [0.6-2.3]. Reported STI rates were similar among men and women (1.1% versus 1.8%), but diagnosed STI rates were twice as high among females versus males (10.4% versus 4.1%, p = 0.007). There were significant differences in the determinants of reported versus diagnosed STIs. In particular, age and sexual orientation were associated with reported STIs, but not with diagnosed STIs. Conversely, STI counseling and depression were associated with STI diagnosis but not with STI reports. CONCLUSION: This study underlines the need to use biomarkers in population-based surveys, given the differential and substantial underreporting of STIs. Results also highlight the need for programmatic adaptation to address gender inequalities in STI rates, by developing women's health services in the French military. Addressing such needs not only benefits women but could also serve as a strategy to reduce overall STI rates as most military women have military partners, increasing the risk of internal transmission.

Ovulatory status and menstrual cycle duration assessed by self-collection of urine on pH strips in a population-based sample of French women not using hormonal contraception.

BACKGROUND: Assessing menstrual cycle function in the general population using a non-invasive method is challenging, both in non-industrialized and industrialized countries. SUBJECTS AND METHODS: The Observatory of Fecundity in France (Obseff) recruited on a nationwide basis a random sample of 943 women aged 18-44 years with unprotected intercourse. A sub-study was set up to assess the characteristics of a menstrual cycle by using a non-invasive method adapted to the general population. Voluntary women were sent a collection kit by the post and requested to collect urine samples on pH strips, together with daily recording of reproductive-related information during a full menstrual cycle. A total of 48 women collected urine every day, whereas 160 women collected urine every other day. Immunoassays were used to measure pregnanediol-3-α-glucuronide, estrone-3-glucuronide and creatinine. Ovulation occurrence and follicular phase duration were estimated using ovulation detection algorithms, compared to a gold standard consisting of three external experts in reproductive medicine. RESULTS: Every other day urine collection gave consistent results in terms of ovulation detection with every day collection (intraclass coefficient of correlation, 0.84, 95% confidence interval, 0.76-0.98). The proportion of anovulatory menstrual cycles was 8%. The characteristics of the ovulatory cycles were length 28 (26-34), follicular phase 16 (12-23), luteal phase 13 (10-16) days median (10th-90th percentiles). DISCUSSION-CONCLUSION: Assessing menstrual cycle characteristics based on urine sample spot only collected every other day in population-based studies through a non-invasive, well accepted and cost-limited procedure not requiring any direct contact with the survey team appears feasible and accurate.

Frequency and correlates of unintended pregnancy risk perceptions.

OBJECTIVES: This study is to assess frequency and correlates of women's reports of unintended pregnancy risk in the general population in France. STUDY DESIGN: Data are drawn from the FECOND survey, a national probability survey on sexual and reproductive health conducted in France in 2010. We identified 2969 women ages 15-49years who had heterosexual intercourse in the 4weeks prior to the survey and who were at potential risk of unintended pregnancy. We evaluate women's reports of unintended pregnancy risk in the last 4weeks and identify correlates of such reports using logistic regression modeling. RESULTS: Fifteen percent of women thought that they could have become pregnant in the last 4weeks without wanting to do so. Reports of unintended pregnancy risk were higher among women in very difficult financial situations (OR=1.87 [1.32-2.65]) and foreign-born women (OR=1.53 [1.03-2.29]). Exposure in the form of contraceptive practices and errors in use of contraception were the strongest correlates of women's reports of unintended pregnancy risk, yet among the 9.8% of women who reported inconsistent use of contraception or unprotected intercourse in the last 4weeks, 63% did not think they could have become pregnant unintentionally. CONCLUSIONS: Significant discrepancies between pregnancy exposure and women's report of unintended pregnancy risk call for better SRH educational programs to improve pregnancy awareness in the general population. On the other hand, targeted interventions toward women who report being at risk of unintended pregnancy may contribute toward reducing unintended pregnancies given the frequency of such events.

Men's contraceptive practices in France: evidence of male involvement in family planning.

OBJECTIVE: To describe contraceptive practices of men in a relationship in France, where use of female-controlled methods is predominant, and to explore their involvement in managing contraception within the couple. STUDY DESIGN: Data are drawn from a national probability cross-sectional survey on sexual and reproductive health conducted in France in 2010. The study sample comprised 3373 men aged 15-49, 1776 of whom were asked about their current contraceptive practices after they reported that they were fecund and sexually active and did not currently want a child. Analyses were performed with logistic regression models. RESULTS: Few men aged 15-49 with a partner did not use contraception (3.4%). Most reported using only a female method (71.7%), 20.4% only cooperative methods, such as condoms, withdrawal and the rhythm method and 4.5% both. Among contraceptive users, withdrawal (7.7%) was more likely to be used by men with low incomes or low educational levels. Condom use was reported as a contraceptive method by 18.9% of men. Its prevalence was higher for those in new and noncohabiting relationships (36.1%) and lower for those in cohabiting relationships (12.4%), in which STIs/HIV prevention is less of a concern. CONCLUSION: Men's high awareness of contraceptive practices and their use of some cooperative methods reveal their involvement in contraceptive practices within the context of relationships. Condom use is associated with the prevention of STIs/HIV for noncohabiting men, but men who live with their female partner seem to use condoms mainly as a contraceptive method. Withdrawal appears to be associated with low level of education and financial difficulties. Finally, having engendered a pregnancy that was terminated appears to influence men's contraceptive practices. IMPLICATIONS: Studying men's contraceptive practices helps to understand their involvement in contraceptive management within relationships.

Male experiences of unintended pregnancy: characteristics and prevalence.

STUDY QUESTION: What are the characteristics and circumstances of pregnancies men report as unintended in France? SUMMARY ANSWER: Pregnancies reported as unintended were most prevalent among young men with insecure financial situations, less stable relationships and inconsistent use of contraception or false assumptions about their partner's use of contraception. WHAT IS KNOWN ALREADY: Efforts to involve men in family planning have increased over the last decade; however, little is known about factors associated with men's pregnancy intentions and associated contraceptive behaviours. STUDY DESIGN, SIZE, DURATION: The data presented in this study were drawn from the nationally representative FECOND study, a population-based survey conducted in France in 2010. The sample comprised 8675 individuals (3373 men), aged 15-49 years, who responded to a telephone interview about socio-demographics and topics related to sexual and reproductive health. The total refusal rate was 20%. PARTICIPANTS/MATERIALS, SETTING, METHODS: This study included 2997 men, of whom 664 reported 893 recent pregnancies (in the 5 years preceding the survey). Multivariate Poisson's regression with population-averaged marginal effects was applied to assess the individual and contextual factors associated with men's intentions for recent pregnancies. The contraceptive circumstances leading to the unintended pregnancies were also assessed. MAIN RESULTS AND THE ROLE OF CHANCE: Of all heterosexually active men, 5% reported they had experienced an unintended pregnancy with a partner in the last 5 years. A total of 20% of recent pregnancies reported by men were qualified to be unintended, of which 45% ended in induced abortion. Of pregnancies following a previous unintended pregnancy, 68% were themselves unintended. Among all heterosexually active men, recent experience of an unintended pregnancy was related to age, mother's education, age at first sex, parity, contraceptive method history, lifetime number of female partners and the relationship situation at the time of survey. Recent unintended pregnancies were also related to pregnancy order and to the financial and professional situation at the time of conception. The majority of unintended pregnancies occurred when men or their partners were using contraceptives; 58% of contraceptive users considered that the pregnancy was due to inconsistent use and 39% considered that it resulted from method failure. Half of the non-users who reported an unintended pregnancy thought that their partner was using a contraceptive method. The relative risk of non-use of a contraceptive method during the month of conception of a recent unintended pregnancy was higher among those without a high school degree (IRR = 2.9, CI 1.6, 5.2) and higher among men for whom the pregnancy interfered with education (IRR = 1.8, CI 1.0, 3.1) or work (IRR = 1.9, CI 1.1, 3.6). LIMITATIONS, REASONS FOR CAUTION: From the perspective of men, the unintended pregnancy rates may be underestimated due to a combination of underreporting of abortion and post-rationalization of birth intentions. Our use of a dichotomous measure of unintended pregnancy is unlikely to fully capture the multidimensional construct of pregnancy intentions. WIDER IMPLICATION OF THE FINDINGS: These results call for gender-inclusive family planning programmes, which fully engage men as active participants in their own rights. STUDY FUNDING/COMPETING INTERESTS: The FECOND study was supported by a grant from the French Ministry of Health, a grant from the French National Agency of Research (#ANR-08-BLAN-0286-01; PIs N.B., C.M.), and funding from National Institute of Health and Medical Research (INSERM) and the National Institute for Demographic Research (INED). None of the authors have competing interests.

Unplanned or unwanted? A randomized study of national estimates of pregnancy intentions.

OBJECTIVE: To evaluate the effect of question wording on national estimates of pregnancy intentions. DESIGN: Data drawn from a national probability survey. SETTING: The FECOND study in France in 2010. PATIENT(S): Five thousand two hundred and seventy-two women and 3,373 men who reported 11,603 pregnancies. INTERVENTION(S): Participants randomly assigned to answer 1 of 2 questions on whether they had planned or wanted each of their pregnancies. MAIN OUTCOMES MEASURE(S): Generalized estimated equation regression models used to test for differences in pregnancy intentions by question wording. RESULT(S): The use of different wording yielded a 6% point difference in estimates: 33.5% pregnancies were "unplanned," and 27.4% were "unwanted." The addition of information on reasons for not using contraception at the time of conception lead to significant recoding, which resulted in a significant reduction in the wording effect: 23.7% (95% CI 22.4-25.0) of pregnancies were unplanned, and 21.2% (95% CI 19.9-22.5) were unwanted. Results from the multivariate analysis confirm the greater chance of reporting an unplanned as compared with an unwanted pregnancy (relative risk 1.25 [95% CI 1.17-1.33]), even after recoding (relative risk 1.15 [95% CI 1.06-1.24]). CONCLUSION(S): This study shows the strong effect of question wording on estimates of pregnancy intentions. The results also support the value of adding information on reasons for nonuse of contraception when assessing pregnancy intentions.

Timing of contraceptive initiation and association with future sexual and reproductive outcomes.

STUDY QUESTION: Who initiates contraception before, at the time or after first sexual intercourse and how does timing of initiation affect future sexual and reproductive health (SRH) outcomes? SUMMARY ANSWER: Earlier initiation was associated with current utilization of more effective contraception, but had no impact on future unintended pregnancy, abortion or sexually transmitted infection rates, while later initiation was linked to higher rates of unintended pregnancies and abortions. WHAT IS KNOWN ALREADY: Contraceptive behaviour at first intercourse is associated with later SRH outcomes. STUDY DESIGN, SIZE, DURATION: Data were drawn from the FECOND study, the last national SRH study in France, conducted in 2010-2011 by phone among 8645 individuals aged 15-49 years. PARTICIPANTS/MATERIALS, SETTING, METHODS: Analysis was performed among 1552 women under the age of 30 years who were sexually experienced and had used contraception at some point. We used logistic regression models to identify factors associated with timing of contraception initiation relative to first intercourse (earlier, at the time and later) and its predictive value on future sexual and reproductive outcomes. MAIN RESULTS AND THE ROLE OF CHANCE: Timing of contraceptive initiation across all three categories (earlier, at the time and later initiators) was dependent on women's age at the time of the survey, country of birth, education level, ease of discussing sex with mother and age of first sex. Using at the time initiators as a reference, later initiators had higher odds of unintended pregnancy [odds ratio (OR) = 1.8] and abortion (OR = 1.9), while earlier initiators were more likely to be using more effective contraception at the time of the survey (OR = 1.8). LIMITATIONS, REASONS FOR CAUTION: The exclusion of sexually inexperienced women, a quarter of which had ever used the pill, may have reduced the scope of our analysis on the relevance of contraceptive initiation for non-contraceptive benefits. WIDER IMPLICATIONS OF THE FINDINGS: The promotion of early initiation of contraception may contribute to long-term use of more effective methods of contraception. STUDY FUNDING/COMPETING INTERESTS: The FECOND study was supported by a grant from the French Ministry of Health, a grant from the French National Agency of Research (#ANR-08-BLAN-0286-01; PIs N. Bajos, C Moreau) and funding from the National Institute of Health and Medical Research (INSERM) and the National Institute for Demographic Research (INED). None of the authors have a conflict of interest.

Effectiveness of family planning policies: the abortion paradox.

OBJECTIVE: The relation between levels of contraceptive use and the incidence of induced abortion remains a topic of heated debate. Many of the contradictions are likely due to the fact that abortion is the end point of a process that starts with sexual activity, contraceptive use (or non-use), followed by unwanted pregnancy, a decision to terminate, and access to abortion. Trends in abortion rates reflect changes in each step of this process, and opposing trends may cancel each other out. This paper aims to investigate the roles played by the dissemination of contraception and the evolving norms of motherhood on changes in abortion rates. METHODS: Drawing data from six national probability surveys that explored contraception and pregnancy wantedness in France from 1978 through 2010, we used multivariate linear regression to explore the associations between trends in contraceptive rates and trends in (i) abortion rates, (ii) unwanted pregnancy rates, (iii) and unwanted birth rates, and to determine which of these 3 associations was strongest. FINDINGS: The association between contraceptive rates and abortion rates over time was weaker than that between contraception rates and unwanted pregnancy rates (p = 0.003). Similarly, the association between contraceptive rates and unwanted birth rates over time was weaker than that between contraceptive rates and unwanted pregnancy rates (p = 0.000).

Estimates of unintended pregnancy rates over the last decade in France as a function of contraceptive behaviors.

OBJECTIVE: We investigate trends in contraceptive behaviors in France and how they may have contributed to fluctuations in unintended pregnancy rates over time and across subgroups of the population between 2000 and 2010. STUDY DESIGN: Data are drawn from three national surveys in France, comprising 4714 women ages 15 to 49 in 2000, 8613 in 2005 and 5260 in 2010. We used multinomial and simple logistic regression models to explore trends in contraceptive behaviors over time. We estimated trends in unintended pregnancy rates in relation to population shifts in contraceptive behaviors between 2000 and 2010. RESULTS: A third of women were not using contraception at the time of the surveys. However, only 2.4% in 2000, 3.2% in 2005 and 2.4% in 2010 had an unmet need for contraception (p=.002). Among contraceptive users, user-dependent hormonal methods decreased from 59% in 2000 to 52% in 2010 (p<.0001), while long-acting reversible methods increased from 22% to 24% (p=.04). Changes in contraceptive behaviors resulted in fluctuations in unintended pregnancy rates estimated to have risen from 3.16% to 3.49% between 2000 and 2005, and to have decreased to 3.26% in 2010. Small changes in unmet need for contraception exerted the largest effects. CONCLUSION: This study indicates that changes in contraceptive behaviors over the past decade in France have potentially resulted in significant fluctuations in unintended pregnancy rates. Our results also demonstrate that a simple algorithm combining contraceptive behaviors and typical-use failure rates may be an acceptable proxy for monitoring trends in unintended pregnancies. IMPLICATIONS: This study offers a framework towards assessing trends in unintended pregnancies, when data on abortions and unintended births are not available. In the context of high contraceptive coverage, gaps of use undermine efforts to improve contraceptive effectiveness, as small fluctuations in unmet need contribute significantly to trends in unintended pregnancy rates.

IUD use in France: women's and physician's perspectives.

OBJECTIVE: While the intra-uterine device (IUD) is the second most popular contraceptive method in France, its use remains low among women most at risk of unintended pregnancies. Acknowledging the conjoint role of women and physicians in contraceptive decision making, we investigate the determinants of IUD use and IUD recommendations from the user and prescriber perspectives. STUDY DESIGN: Data are drawn from 2 national probability surveys (population-based and physician surveys) on sexual and reproductive health in France. The population based survey comprised 3,563 women ages 15-49 at risk of an unintended pregnancy in 2010 and the physician survey included 364 general practitioners (GPs) and 401 gynecologists practicing in private offices in 2010-2011. Analyses were performed using logistic regression models. RESULTS: Altogether, 21.4% of women were IUD users, with substantial differences by age and parity. Less than 1% of young women (<25 years) and 3% of nulliparous were current IUD users in 2010. The odds of IUD use were four times higher in women followed by a gynecologist as compared to a GP. Mirroring these results, gynecologists were more likely to recommend IUDs than GPs. Misconception about IUD risks was widespread among women and providers. Medical training and information, professional practice settings, and ever use of IUDs also informed physician's likelihood of recommending IUDs, regardless of specialty. CONCLUSIONS: The study reveals the intersection of individual and professional influences on contraceptive use patterns. The considerable age discrepancy in IUD use in France, with very few young women most at risk of an unintended pregnancy using the method, reflects a knowledge gap shared by users and providers. These findings suggest there are significant opportunities to improve contraceptive care in France. IMPLICATIONS: This study stresses the need to inform women and doctors about the benefits and risks of IUDs for all women. Substantial efforts are required to improve the medical curriculum, in order to promote evidenced based family planning counseling and provide GPs with the technical skills to insert IUDs.

Trends and determinants of use of long-acting reversible contraception use among young women in France: results from three national surveys conducted between 2000 and 2010.

OBJECTIVE: To investigate trends and determinants in the use of long-acting reversible contraceptives (LARCs), including intrauterine devices and implants, over the last decade among young women in France. DESIGN: Data drawn from three cross-sectional national probability surveys. SETTING: Not applicable. PATIENT(S): A total of 1,204 women, ages 15 to 29, who are at potential risk of an unintended pregnancy in 2000; 1,921 in 2005; and 1,281 in 2010. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Logistic regression models were used to explore trends in LARC use since 2000 and to examine determinants of LARC use in 2010. RESULT(S): A minority of women were using LARC methods, with a significant increase between 2000 and 2010, from 4.6% to 6.4%. The odds of LARC use in 2010 were higher among women 20 to 29 years, parous women, women with a history of unintended pregnancy, women in difficult financial situations, smokers, and women in the care of a gynecologist. CONCLUSION(S): This study shows that little progress has been made in LARC use among young women in France, despite these methods being widely available and reimbursed by the national health system.

Maternal exposure to nitrogen dioxide during pregnancy and offspring birth weight: comparison of two exposure models.

BACKGROUND: Studies of the effects of air pollutants on birth weight often assess exposure with networks of permanent air quality monitoring stations (AQMSs), which have a poor spatial resolution. OBJECTIVE: We aimed to compare the exposure model based on the nearest AQMS and a temporally adjusted geostatistical (TAG) model with a finer spatial resolution, for use in pregnancy studies. METHODS: The AQMS and TAG exposure models were implemented in two areas surrounding medium-size cities in which 776 pregnant women were followed as part of the EDEN mother-child cohort. The exposure models were compared in terms of estimated nitrogen dioxide (NO2) levels and of their association with birth weight. RESULTS: The correlations between the two estimates of exposure during the first trimester of pregnancy were r = 0.67, 0.70, and 0.83 for women living within 5, 2, and 1 km of an AQMS, respectively. Exposure patterns displayed greater spatial than temporal variations. Exposure during the first trimester of pregnancy was most strongly associated with birth weight for women living < 2 km away from an AQMS: a 10-µg/m3 increase in NO2 exposure was associated with an adjusted difference in birth weight of -37 g [95% confidence interval (CI), -75 to 1 g] for the nearest-AQMS model and of -51 g (95% CI, -128 to 26 g) for the TAG model. The association was less strong (higher p-value) for women living within 5 or 1 km of an AQMS. CONCLUSIONS: The two exposure models tended to give consistent results in terms of association with birth weight, despite the moderate concordance between exposure estimates.

Maternal personal exposure to airborne benzene and intrauterine growth.

BACKGROUND: Studies relying on outdoor pollutants measures have reported associations between air pollutants and birth weight. OBJECTIVE: Our aim was to assess the relation between maternal personal exposure to airborne benzene during pregnancy and fetal growth. METHODS: We recruited pregnant women in two French maternity hospitals in 2005-2006 as part of the EDEN mother-child cohort. A subsample of 271 nonsmoking women carried a diffusive air sampler for a week during the 27th gestational week, allowing assessment of benzene exposure. We estimated head circumference of the offspring by ultrasound measurements during the second and third trimesters of pregnancy and at birth. RESULTS: Median benzene exposure was 1.8 microg/m(3) (5th, 95th percentiles, 0.5, 7.5 microg/m(3)). Log-transformed benzene exposure was associated with a gestational age-adjusted decrease of 68 g in mean birth weight [95% confidence interval (CI), -135 to -1 g] and of 1.9 mm in mean head circumference at birth (95% CI, -3.8 to 0.0 mm). It was associated with an adjusted decrease of 1.9 mm in head circumference assessed during the third trimester (95% CI, -4.0 to 0.3 mm) and of 1.5 mm in head circumference assessed at the end of the second trimester of pregnancy (95% CI, -3.1 to 0 mm). CONCLUSIONS: Our prospective study among pregnant women is one of the first to rely on personal monitoring of exposure; a limitation is that exposure was assessed during 1 week only. Maternal benzene exposure was associated with decreases in birth weight and head circumference during pregnancy and at birth. This association could be attributable to benzene and a mixture of associated traffic-related air pollutants.