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Study design: This was a case-control study of women evaluated and delivered at our institution from 2011 to 2015. Spontaneous PTD was defined as delivery before 37 weeks due to spontaneous preterm labor or premature rupture of membranes. Patient with multifetal gestation and those with medically indicated term or PTD were excluded.
Results: Of 877 women meeting the inclusion criteria, 173 delivered preterm and 704 delivered at term, and 8.1% had high free β-hCG in one or both trimesters. High maternal first and/or second trimester free β-hCG (≥95th percentile) was associated with lower rates of PTD. Thirty-two women with high free β-hCG in both first and second trimesters delivered at term. Gestational age at delivery and birth weights were lower in women who did not have high free β-hCG in any trimester. Low free β-hCG (≤5th percentile) in either trimester was not associated with an increased or decreased likelihood of PTD. Logistic regression demonstrated an independent association of high free β-hCG (≥95th percentile) with a reduced likelihood of PTD. Stratified analysis revealed a stronger impact of this association in women with no prior history of PTD.
Conclusions: High free β-hCG, in the absence of risk factors for medically indicated PTD, is associated with a reduced likelihood of spontaneous PTD and may represent a marker indicating lower risk. 相似文献
Methods: This case–control study included 440 women with surgically confirmed endometriosis (cases) and 880 women without endometriosis (controls). Information on early-life factors was ascertained retrospectively by in-person interviews with participants and their mothers. Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for the associations between endometriosis and maternal and paternal characteristics and foetal and infant exposures were estimated using unconditional logistic regression, adjusting for frequency matching and confounding variables.
Results: We observed that women who were not breastfed as infants had twice the risk of endometriosis compared with women who were breastfed (adjusted OR 2.0; 95% CI 1.6, 4.5). Our data suggested an increased endometriosis risk with neonatal vaginal bleeding (adjusted OR 1.9; 95% CI 1.2, 4.3) and paternal smoking (adjusted OR 1.8; 95% CI 1.1, 4.9). Although the CIs included the null hypothesis value, caesarean section (adjusted OR 1.7; 95% CI 1.0, 3.5) and prematurity (adjusted OR 1.4; 95% CI 0.8, 3.7) were probably associated with the incidence of endometriosis.
Conclusions: Some early-life factors including breastfeeding, neonatal vaginal bleeding and paternal smoking were associated with subsequent, surgically confirmed endometriosis in this cohort of Chinese women. 相似文献