Exposure to toxic environmental chemicals during pregnancy and breastfeeding is ubiquitous and is a threat to healthy human reproduction. There are tens of thousands of chemicals in global commerce, and even small exposures to toxic chemicals during pregnancy can trigger adverse health consequences. Exposure to toxic environmental chemicals and related health outcomes are inequitably distributed within and between countries; universally, the consequences of exposure are disproportionately borne by people with low incomes. Discrimination, other social factors, economic factors, and occupation impact risk of exposure and harm. Documented links between prenatal exposure to environmental chemicals and adverse health outcomes span the life course and include impacts on fertility and pregnancy, neurodevelopment, and cancer. The global health and economic burden related to toxic environmental chemicals is in excess of millions of deaths and billions of dollars every year. On the basis of accumulating robust evidence of exposures and adverse health impacts related to toxic environmental chemicals, the International Federation of Gynecology and Obstetrics (FIGO) joins other leading reproductive health professional societies in calling for timely action to prevent harm. FIGO recommends that reproductive and other health professionals advocate for policies to prevent exposure to toxic environmental chemicals, work to ensure a healthy food system for all, make environmental health part of health care, and champion environmental justice.

IntroductionEmerging evidence suggests community health workers (CHWs) delivering preventive maternal and child health (MCH) interventions through home visiting improve several important health outcomes, including initiation of prenatal care, healthy birth weight and uptake of childhood immunisations.Methods and analysisThe Arizona Health Start Program is a behavioral-based home visiting intervention, which uses CHWs to improve MCH outcomes through health education, referral support, and advocacy services for at-risk pregnant and postpartum women with children up to 2 years of age. We aim to test our central hypothesis that mothers and children exposed to this intervention will experience positive health outcomes in the areas of (1) newborn health; (2) maternal health and healthcare utilisation; and (3) child health and development. This paper outlines our protocol to retrospectively evaluate Health Start Program administrative data from 2006 to 2015, equaling 15 576 enrollees. We will use propensity score matching to generate a statistically similar control group. Our analytic sample size is sufficient to detect meaningful programme effects from low-frequency events, including preterm births, low and very low birth weights, maternal morbidity, and differences in immunisation and hospitalisation rates.Ethics and disseminationThis work is supported through an inter-agency contract from the Arizona Department of Health Services and is approved by the University of Arizona Research Institutional Review Board (Protocol 1701128802, approved 25 January 2017). Evaluation of the three proposed outcome areas will be completed by June 2020.

ObjectiveTo test if participation in the Health Start Programme, an Arizona statewide Community Health Worker (CHW) maternal and child health (MCH) home visiting programme, reduced rates of low birth weight (LBW), very LBW (VLBW), extremely LBW (ELBW) and preterm birth (PTB).DesignQuasi-experimental retrospective study using propensity score matching of Health Start Programme enrolment data to state birth certificate records for years 2006–2016.SettingArizona is uniquely racially and ethnically diverse with comparatively higher proportions of Latino and American Indian residents and a smaller proportion of African Americans.Participants7212 Health Start Programme mothers matched to non-participants based on demographic, socioeconomic and geographic characteristics, health conditions and previous birth experiences.InterventionA statewide CHW MCH home visiting programme.Primary and secondary outcome measuresLBW, VLBW, ELBW and PTB.ResultsUsing Health Start Programme’s administrative data and birth certificate data from 2006 to 2016, we identified 7212 Health Start Programme participants and 53 948 matches. Programme participation is associated with decreases in adverse birth outcomes for most subgroups. Health Start participation is associated with statistically significant lower rates of LBW among American Indian women (38%; average treatment-on-the-treated effect (ATT): 2.30; 95% CI −4.07 to –0.53) and mothers with a pre-existing health risk (25%; ATT: -3.06; 95% CI −5.82 to –0.30). Among Latina mothers, Health Start Programme participation is associated with statistically significant lower rates of VLBW (36%; ATT: 0.35; 95% CI −0.69 to –0.01) and ELBW (62%; ATT: 0.31; 95% CI (−0.52 to –0.10)). Finally, Health Start Programme participation is associated with a statistically significant lower rate of PTB for teen mothers (30%; ATT: 2.81; 95% CI −4.71 to –0.91). Other results were not statistically significant.ConclusionA state health department-operated MCH home visiting intervention that employs CHWs as the primary interventionist may contribute to the reduction of LBW, VLBW, ELBW and PTB and could improve birth outcomes statewide, especially among women and children at increased risk for MCH inequity.

Objectives Social and structural barriers drive disparities in prenatal care utilization among minoritized women in the United States. This study examined the impact of Arizona’s Health Start Program, a community health worker (CHW) home visiting intervention, on prenatal care utilization among an ethno-racially and geographically diverse cohort of women. Methods We used Health Start administrative and state birth certificate data to identify women enrolled in the program during 2006–2016 (n = 7,117). Propensity score matching was used to generate a statistically-similar comparison group (n = 53,213) of women who did not participate in the program. Odds ratios were used to compare rates of prenatal care utilization. The process was repeated for select subgroups, with post-match regression adjustments applied where necessary. Results Health Start participants were more likely to report any (OR 1.24, 95%CI 1.02–1.50) and adequate (OR 1.08, 95%CI 1.01–1.16) prenatal care, compared to controls. Additional specific subgroups were significantly more likely to receive any prenatal care: American Indian women (OR 2.22, 95%CI 1.07–4.60), primipara women (OR 1.64, 95%CI 1.13–2.38), teens (OR 1.58, 95%CI 1.02–2.45), women in rural border counties (OR 1.45, 95%CI 1.05–1.98); and adequate prenatal care: teens (OR 1.31, 95%CI 1.11–1.55), women in rural border counties (OR 1.18, 95%CI 1.05–1.33), primipara women (OR 1.18, 95%CI 1.05–1.32), women with less than high school education (OR 1.13, 95%CI 1.00-1.27). Conclusions for Practice: A CHW-led perinatal home visiting intervention operated through a state health department can improve prenatal care utilization among demographically and socioeconomically disadvantaged women and reduce maternal and child health inequity.

Background Arizona’s Health Start Program is a statewide community health worker (CHW) maternal and child health home visiting intervention. The objective of this study was to test if participation in Health Start during 2006–2016 improved early childhood vaccination completion rates. Methods This retrospective study used 11 years of administrative, birth certificate, and immunization records. Propensity score matching was used to identify control groups, based on demographic, socioeconomic, and geographic characteristics. Results are reported by historically disadvantaged subgroups and/or with a history of low vaccine uptake, including Hispanic/Latinx and American Indian children, and children of low socioeconomic status and from rural areas, children with teen mothers and first-born children. The average treatment-on-the-treated (ATT) effect estimated the impact of Health Start on timely completion of seven early childhood vaccine series: diphtheria/tetanus toxoids and acellular/whole-cell pertussis (DTaP/DTP), Haemophilus influenzae type b (Hib), hepatitis B (Hep. B), measles-mumps-rubella (MMR), pneumococcal conjugate vaccine (PCV13), poliovirus, and varicella. Results Vaccination completion rates (by age five) were 5.0% points higher for Health Start children as a group, and on average 5.0% points higher for several subgroups of mothers: women from rural border counties (ATT 5.8), Hispanic/Latinx women (ATT 4.8), American Indian women (ATT 4.8), women with less than high school education (ATT 5.0), teen mothers (ATT 6.1), and primipara women (ATT 4.5), compared to matched control groups (p-value ≤ 0.05). Time-to-event analyses show Health Start children complete vaccination sooner, with a hazard rate for full vaccination 13% higher than their matches. Conclusion A state-operated home visiting intervention with CHWs as the primary interventionist can effectively promote early childhood vaccine completion, which may reduce the incidence of preventable diseases and subsequently improve children’s health. Effects of CHW interventions on vaccination uptake is particularly relevant given the rise in vaccine-preventable diseases in the US and globally. Trial registration Approved by the University of Arizona Research Institutional Review Board (Protocol 1701128802), 25 January 2017.