Epidemiologic factors and urogenital infections associated with preterm birth in a midwestern U.S. population.

OBJECTIVE: To correlate epidemiologic factors with urogenital infections associated with preterm birth. METHODS: Pregnant women were sequentially included from four Wisconsin cohorts: large urban, midsize urban, small city, and rural city. Demographic, clinical, and current pregnancy data were collected. Cervical and urine specimens were analyzed by microscopy, culture, and polymerase chain reaction for potential pathogens. RESULTS: Six hundred seventy-six women were evaluated. Fifty-four (8.0%) had preterm birth: 12.1% (19/157) large urban, 8.8% (15/170) midsize urban, 9.4% (16/171) small city, and 2.3% (4/178) rural city. Associated host factors and infections varied significantly among sites. Urogenital infection rates, especially Mycoplasma hominis and Ureaplasma parvum, were highest at the large urban site. Large urban site, minority ethnicity, multiple infections, and certain historical factors were associated with preterm birth by univariable analysis. By multivariable analysis, preterm birth was associated with prior preterm birth (adjusted odds ratio [aOR] 2.76, 95% confidence interval [CI] 1.27-6.02) and urinary tract infection (aOR 2.62, 95% CI 1.32-519), and negatively associated with provider-assessed good health (aOR 0.42, 95% CI 0.23-0.76) and group B streptococcal infection treatment (surrogate for health care use) (aOR 0.38, 95% CI 0.15-.99). Risk and protective factors were similar for women with birth at less than 35 weeks, and additionally associated with M hominis (aOR 3.6, 95% CI 1.4-9.7). CONCLUSION: These measured differences among sites are consistent with observations that link epidemiologic factors, both environmental and genetic, with minimally pathogenic vaginal bacteria, inducing preterm birth, especially at less than 35 weeks of gestation.

A novel gene-environment interaction involved in endometriosis.

OBJECTIVE: To establish a well-defined cohort for genetic epidemiology studies of endometriosis and conduct a pilot study to confirm validity using existing data associated with endometriosis. METHODS: Between January and May 2010, a nested cohort within a population-based biobank was established in Marshfield, Wisconsin, USA. The inclusion criteria were women who had laparoscopy or hysterectomy. Fifty-one pleiotropic genetic polymorphisms and other established risk factors, such as smoking status and body mass index, were compared between endometriosis cases and controls. RESULTS: From the existing biobank, 796 cases and 501 controls were identified, and 259 women with endometriosis were enrolled specifically for the nested cohort within this biobank. A single nucleotide polymorphism in the MMP1 gene significantly differed between cases and controls only when stratified by smoking status. Minor allele frequency was higher in control women who smoked than in women with endometriosis who smoked (55.5% versus 45.5%, χ(2)=8.2, P=0.017); the inverse relationship was found in non-smoker control women. CONCLUSIONS: Women with endometriosis were successfully recruited to participate in a general biobank, and a novel gene-environment interaction was identified. The findings suggest that important potential genetic associations may be missed if gene-environment interactions with known epidemiologic risk factors are not considered.