Preterm birth among the hmong, other Asian subgroups and non-hispanic whites in California

Abstract

BackgroundWe investigated very preterm (VPTB) and preterm birth (PTB) risk among Hmong women relative to non-Hispanic whites and other Asian subgroups. We also examined the maternal education health gradient across subgroups.MethodsCalifornia birth record data (2002–2004) were used to analyze 568,652 singleton births to white and Asian women. Pearson Chi-square and logistic regression were used to assess variation in maternal characteristics and VPTB/PTB risk by subgroup.ResultsWhite, Chinese, Japanese, Korean, Asian Indian, and Vietnamese women had 36–59 % lower odds of VPTB and 30–56 % lower odds of PTB than Hmong women. Controls for covariates did not substantially diminish these disparities. Cambodian, Filipino and Lao/Thai women’s odds of VPTB were similar to that of Hmong women. But they had higher adjusted odds of PTB compared to the Hmong. There was heterogeneity in the educational gradient of PTB, with significant differences between the least and most educated women among whites, Chinese, Japanese, Asian Indians, Cambodians, and Laoians/Thais. Maternal education was not associated with PTB for Hmong, Vietnamese and Korean women, however.ConclusionsStudies of Hmong infant health from the 1980s, the decade immediately following the group’s mass migration to the US, found no significant differences in adverse birth outcomes between Hmong and white women. By the early 2000s, however, the disparities in VPTB and PTB between Hmong and white women, as well as between Hmong and other Asian women had become substantial. Moreover, despite gains in post-secondary education among childbearing-age Hmong women, the returns to education for the Hmong are negligible. Higher educational attainment does not confer the same health benefits for Hmong women as it does for whites and other Asian subgroups.

Pregnancy outcomes among Asian Americans of advanced maternal age, 1992–2018

“…Consistent with our data, heterogeneity in preterm birth risk within the Asian American community based on maternal age and specific ethnic subgroup has precedent in the literature 5,13 . Vang et al posited that multivariate risk models for preterm birth should encompass more than maternal sociodemographic characteristics and prenatal care, as these variables alone may not synthesize the complexity of environmental stressors that Asian American mothers may be exposed to in the United States 21 . For example, structural discrimination and socioeconomic barriers to care can adversely influence pregnancy outcomes 22…”

Revealing the variations in impact of economic segregation on preterm birth among disaggregated Asian ethnicities across MSAs in the United States: 2015–2017

“…Considering that nearly 1 in 10 births are preterm deliveries, representing about 400,000 PTBs in 2016, it is important to understand the potential causes and risk factors for PTB to prevent the mortality and morbidity outcomes that occur due to preterm deliveries ( Martin et al, 2018 ). Risk factors identified include previous preterm delivery, cigarette smoking, gestational diabetes and preeclampsia, maternal age, and socioeconomic status ( Cripe et al, 2012 ; Fuchs et al, 2018 ; Gibbs et al, 2012 ; Hedderson, 2003 ; Kyrklund-Blomberg & Cnattingius, 1998 ; Mercer et al, 1999 ; Smith et al, 2007 ; Thompson, 2002 ; Vang et al, 2015 ).…”

Advancing Health Disparities Research: The Need to Include Asian American Subgroup Populations

“…Reported that Filipinas had higher incidence rates (12.62), while Rao et al (2006) reported that Vietnamese had a higher incidence rate (12.4) of preterm delivery less than 32 weeks [ 83 , 85 ]. However, one generally consistent finding across the studies was that the rates of preterm deliveries were lower in East Asian American subgroups (Chinese, Japanese, and Korean) than in other subgroups [ 82 , 83 , 85 , 86 ]. See Table 7 for incidence rates.…”

“…Five articles included pregnancy-associated hypertension, preeclampsia, and/or eclampsia [ 82 , 83 ]. Two included incidence rates for preeclampsia for the Indian/Pakistani, Japanese, Chinese, Filipina, Korean, and Vietnamese subgroups, and one study included prevalence rates for Cambodian, Lao, Vietnamese, and Japanese females [ 84 – 86 ]. The five studies indicated that Filipina women had the highest incidences of PAH (2.86; 6.3), preeclampsia (6.8; 1.5), and eclampsia (0.19) of all the Asian subgroups considered (See Table 7 for incidence comparison).…”

“…Four articles included incidence rates on either or both preterm deliveries less than 37 weeks and preterm deliveries less than 32 weeks among Chinese, Japanese, Filipina, Asian Indian, Indian/Pakistani, Korean, Vietnamese, Hmong, Cambodian, and Lao/Thai subgroups [ 82 , 83 , 85 , 86 ]. Among the four studies, the results differed with regard to which subgroups had higher rates, as each study included different subgroups and largely considered different time periods.…”