باروری و ناباروری ایران

Sandie Ha, Ph.D.,a,b Rajeshwari Sundaram, Ph.D.,c Germaine M. Buck Louis, Ph.D.,d Carrie Nobles, Ph.D.,a

Indulaxmi Seeni, B.S.,a Seth Sherman, Ph.D.,e and Pauline Mendola, Ph.D.a

a Epidemiology Branch, Division of Intramural Population Health Research, National Institute of Child Health and Human

Development, Bethesda, Maryland;

b Department of Public Health, School of Social Sciences, Humanities and Arts,

University of California, Merced, California;

c Biostatistics and Bioinformatics Branch and

d Office of the Director,

Division of Intramural Population Health Research, National Institute of Child Health and Human Development,

Bethesda, Maryland; and

e The EMMES Corporation, Rockville, Maryland

Objective: To estimate the association of pregnancy loss with common air pollutant exposure. Ambient air pollution exposure has been

linked to adverse pregnancy outcomes, but few studies have investigated its relationship with pregnancy loss.

Design: Prospective cohort study.

Setting: Not applicable.

Patient(s): A total of 343 singleton pregnancies in a multisite prospective cohort study with detailed protocols for ovulation and

pregnancy testing.

Intervention(s): None.

Main Outcome Measure(s): Timing of incident pregnancy loss (from ovulation).

Result(s): The incidence of pregnancy loss was 28% (n ¼ 98). Pollutant levels at women's residences were estimated using modified

Community Multiscale Air Quality models and averaged during the past 2 weeks (acute) and the whole pregnancy (chronic). Adjusted

Cox proportional hazards models showed that an interquartile range increase in average whole pregnancy ozone (hazard ratio [HR] 1.12,

95% confidence interval [CI] 1.07–1.17) and particulate matter <2.5 mm (HR 1.13, 95% CI 1.03–1.24) concentrations were associated

with faster time to pregnancy loss. Sulfate compounds also appeared to increase risk (HR 1.58, 95% CI 1.07–2.34). Last 2 weeks of

exposures were not associated with loss.

Conclusion(s): In a prospective cohort of couples trying to conceive, we found evidence that exposure to air pollution throughout

pregnancy was associated with loss, but delineating specific periods of heightened vulnerability await larger preconception cohort

studies with daily measured air quality. (Fertil Steril
2018;109:148–53. 2017 by American Society for Reproductive Medicine.)