The Association of Moms2B, a Community-Based Interdisciplinary Intervention Program, and Pregnancy and Infant Outcomes among Women Residing in Neighborhoods with a High Rate of Infant Mortality

Abstract

Objectives

We evaluated the effectiveness of Moms2B, a community-based group pregnancy and parenting program, in an effort to assess whether the program improved pregnancy and infant outcomes.

Methods

We conducted a retrospective matched exposure cohort study comparing women exposed to the Moms2B program during pregnancy (two or more prenatal visits) who delivered a singleton live birth or stillbirth (≥ 20 weeks gestation) from 2011–2017 to a closely matched group of women not exposed to the program. Primary outcomes were preterm birth and low birth weight. Propensity score methods were used to provide strong control for confounders.

Results

The final analytic file comprised 675 exposed pregnancies and a propensity score-matched group of 1336 unexposed pregnancies. Most of the women were non-Hispanic Black. We found evidence of better outcomes among pregnancies exposed to Moms2B versus unexposed pregnancies, particularly for the primary outcome of low birth weight [9.45% versus 12.00%, respectively, risk difference (RD) = −2.55, 95% confidence interval (CI) = (−5.44, 0.34)]. Point estimates for all adverse pregnancy outcomes uniformly favored exposure to Moms2B.

Conclusions for Practice

Our findings suggest that participation in the Moms2B program improves pregnancy and infant outcomes. The program offers an innovative group model of pregnancy and parenting support for women, especially in non-Hispanic Black women with high-risk pregnancies.

Introduction

Infant mortality, defined as the death of a live born infant within the first year of life, is a measure of population health and is a direct reflection of maternal and infant well-being (State Infant Mortality Collaborative 2013). While the rate of infant mortality in the U.S. has decreased over time, there remains marked racial disparities with non-Hispanic Black infants more than twice as likely to die as non-Hispanic white infants (Jacob 2016). Non-Hispanic Black infants are also more likely to be born preterm (13.6% versus 9.0%) or very preterm (3.0% vs 1.3%) compared to non-Hispanic white infants (March of Dimes Peristats 2019). These excess very preterm births are the primary cause of the Black-white disparity in infant mortality (Riddell et al. 2017; Schempf et al. 2007). Causes of preterm births are complex and multifactorial, but can often be traced to maternal health status prior to pregnancy (Haas et al. 2005).

Traditional biomedical models of prenatal care offered in a clinical setting have failed to eliminate the racial disparities in infant mortality (Lu et al. 2010). While several frameworks have been proposed for examining perinatal health, a life course approach is the most comprehensive. The model considers the health of the woman throughout her lifetime and the social determinants of health (e.g., poverty, stress, racism) including those acting at the neighborhood and societal levels as important contributors to pregnancy outcome (Misra et al. 2003; Peck et al. 2010). In brief, there is evidence to suggest that exposure to adversity (e.g., structural racism, toxic stress) over time can result in physiologic changes that negatively impact women’s health and can contribute to adverse pregnancy outcomes, even if the woman receives optimal clinical care during pregnancy (Geronimus 1996; Geronimus et al. 2006; Lu and Halfon 2003; Lu et al. 2010).

The state of Ohio has one of the highest rates of infant mortality in the United States, with 7.2 infant deaths per 1000 live births (Ohio Department of Health 2019). In 2010, in an effort to decrease adverse pregnancy outcomes and the high rate of infant mortality and associated racial disparities, a multidisciplinary group pregnancy and parenting support program, Moms2B, was developed in the academic departments of pediatrics and obstetrics and gynecology. Moms2B began in one high-risk neighborhood in Columbus, Ohio and has expanded to eight neighborhoods, including six churches, through local and state support (Gabbe et al. 2017). With a multidisciplinary team at each weekly two-hour session, the Moms2B group model of care provides pregnancy, parenting, health, and life skills education, plus social support, case management, and care coordination for women at sites located in neighborhoods with high rates of infant mortality.

In an effort to evaluate the effectiveness of Moms2B in improving pregnancy and infant outcomes after eight full years of program implementation, we used robust causal inference methods to compare the outcome of pregnancies exposed to Moms2B to a similar group of pregnancies that were not exposed. Our hypothesis was that women exposed to Moms2B would have fewer preterm births and low birth weight infants than mothers not exposed to the program.

Methods

Study Design and Sample

We used a matched exposure retrospective cohort design. Eligibility criteria are presented in Table 1. A priori, the decision was made to focus on pregnant women with a singleton gestation who experienced a live birth or stillbirth from 2011–2017, as the first half-year of the program in 2010 was a pilot.

Table 1.

Inclusion criteria, Moms2B program evaluation, 2011–2017

Singleton pregnancy

Live birth or fetal death from 2011–2017

Pregnancies to women ≥ 12 years olda

Gestational age ≥ 20 weeksa

Residence in Franklin County, OHa

Insurance was Medicaid or woman was uninsureda

Participant record could be linked to a birth or fetal death

Woman’s first pregnancy exposed (≥ 2 visits) to Moms2Bb

^aAt index birth or stillbirth

^bAll other pregnancies from 2011–2017 were excluded

Human Subjects Considerations

The research was conducted according to prevailing ethical principles. The study was reviewed and approved by the Institutional Review Boards (IRB) at The Ohio State University and the Ohio Department of Health. The IRB approved a waiver of informed consent for this project.

Analytic File Creation

Investigators used a combination of Moms2B attendance data and Ohio Vital Records Data (i.e., birth, death, and fetal death records) from 2010–2017 to assemble the analytic file. As shown in Fig. 1 and as described in detail in the online supplement, Moms2B program data were linked to Ohio birth, death, and fetal death records using a probabilistic linking procedure that included the woman’s first, last, and maiden name, woman’s date of birth, and infant’s date of birth. Linkages were deemed a potential match if the probability of a correct linkage was > 80%. All potential links were reviewed for accuracy by one of the investigators and Moms2B program staff. Discrepancies were resolved via discussion. Exposed pregnancies meeting the study eligibility criteria (Table 1) that could be linked to a vital record comprised the exposed group. A sample of the remaining pregnancies meeting the study eligibility criteria were considered unexposed to Moms2B. All links were finalized before outcomes were examined.

Fig. 1. STROBE diagram, study data flow, Moms2B program evaluation, 2011–2017.

* At the time of the live birth or the fetal death.

** All pregnancies touched by Moms2B were identified in the vital records at this step and the pregnancies involving only one visit to Moms2B were removed (n=2A9), as they were considered only partially exposed to Moms2B (i.e., neither fully exposed nor un exposed).

† Zip code identified by the county as being high-risk for infant mortality as well as zip codes in which Moms2B-exposed women reported living.

⧧ See Methods for complete discussion of matching procedure.

Intervention (Exposure)

Moms2B’s multidisciplinary clinical team includes nurses, lactation counselors, dietitians, social workers, child development and parenting specialists, community navigators and health workers, pediatricians, obstetricians, and a fatherhood expert. All staff are trained to provide trauma-informed care using techniques to mitigate toxic stress (Garner et al. 2012). Moms2B sessions occur in the same locations at the same time each week, serving as anchors in the communities they serve (Koh et al. 2020).

Weekly two-hour Moms2B sessions begin with “sister/brother circle” in which participants and their support person (if present) sit together with Moms2B staff in a collaborative learning environment. Pregnant and parenting women divide into separate groups to discuss topics relevant to pregnancy or infant care, respectively. Education efforts in Moms2B are grounded in the life course approach with much of the content focused on maintaining women’s overall health during and after pregnancy, with consideration for optimizing health as a parent and for any future pregnancies. Standardized educational lessons are taught on a rotating basis by the Moms2B team. The topics are comprehensive, ranging from nutrition to car seat safety. Colorful and easy to understand handouts summarizing the lessons are distributed for attendees to take home. Developmentally stimulating childcare is provided onsite so that women are able to focus on the lessons. Following a life course model, the program aims to optimize infant health and development by ensuring mothers are connected to well child care for check-ups, immunizations, and developmental intervention, as needed. Before the session ends, case managers meet one-on-one with women to review and discuss women’s current health and social situation and to connect them to resources as needed. During this time, a healthy hot meal is served to all attendees. In addition to the weekly program, one-on-one support and follow-up during the week are provided. For women who stop coming to Moms2B sessions, case workers attempt to contact them for up to three months before women are considered lost to follow-up. Each Moms2B site has regular visits from the local food bank and the mobile clinic of the local children’s hospital. Women are encouraged to participate in the program until their index child turns one. A more comprehensive description of the program can be found elsewhere (Gabbe et al. 2017).

A priori, exposure to Moms2B was defined as two or more visits to Moms2B during the index pregnancy, as the first visit to Moms2B is primarily introductory in nature.

Outcomes

The primary outcomes of interest were preterm birth and low birth weight. Preterm birth was defined as live birth prior to 37 completed weeks of gestation. Low birth weight was defined as birth weight less than 2500 g. Secondary outcomes included: very preterm birth (< 32 weeks) and extreme preterm birth (< 28 weeks), stillbirth, and perinatal and infant mortality. Stillbirths were fetal deaths occurring at 20 weeks of gestation or later. Perinatal mortality included stillbirths occurring at 20 weeks of gestation or later and infant deaths ≤ 28 days of life. Infant mortality was defined as death of a live born infant within the first year (≤ 365 days) of life.

Statistical Analysis

Propensity Score Estimation and Approach

Propensity score methods were used to provide strong control for confounders in order to permit examination of the impact of Moms2B on pregnancy outcomes given that the intervention was not randomly assigned (D’Agostino 1998). A propensity score, the probability of being exposed to Moms2B (≥ 2 visits during pregnancy), was estimated for each pregnancy via logistic regression (Rosenbaum and Rubin 1983). Missing data were imputed for use in estimating the propensity score (details are described in the online supplement) (Hill 2004; Kenward and Carpenter 2007; Little and Wang 1996; Mitra and Reiter 2016; Penning de Vries and Groenwold 2016); the covariates noted in Table 2 were used to estimate the propensity score.

Table 2.

Pregnancy cohort characteristics prior to and after 1:2 propensity score matching, Moms2B program evaluation, 2011–2017

	Complete cohort		After 1:2 match
	Exposed (n = 675) %	Not exposed (n = 58,287) %	Exposed (n = 675) %	Not exposed (n = 1,336) %	Absolute standardized dif ference d
Age of woman (years)a,b	25.3 (6.1)	26.7 (5.8)	25.3 (6.1)	25.3 (5.8)	1.0
Woman’s racea
White	21.2	39.8	20.6	19.0	4.0
Black	72.0	45.5	72.0	73.3	2.9
Other	5.4	11.9	5.5	5.6	0.6
Missing	1.9	2.8	1.9	2.1	1.2
Woman of hispanic ethnicitya
Yes	4.3	12.4	4.3	5.2	4.4
No	93.8	85.2	93.5	91.9	6.0
Missing	1.9	2.4	2.2	2.8	4.0
Married at time of birtha
Yes	15.0	35.5	15.0	14.0	2.7
No	84.7	64.4	84.7	86.0	3.6
Missing	0.3	0.02	0.3	0	7.7
Woman’s educationa
< HS	29.0	28.1	29.0	27.8	2.6
HS Grad or GED	40.0	32.0	40.0	40.0	0.2
> HS	29.2	36.7	29.2	29.2	0.01
Missing	1.8	3.1	1.8	2.8	7.1
Paritya,b	1.3 (1.6)	1.6 (1.7)	1.3 (1.6)	1.3 (1.7)	0.3
Number of living childrena,b	1.2 (1.5)	1.5 (1.6)	1.2 (1.5)	1.2 (1.6)	0.5
Previous pre-term birtha,b,c
Yes	11.0	7.9	11.0	11.7	2.3
No	88.9	91.4	88.9	88.3	2.0
Missing	0.2	0.8	0.2	0.1	2.2
Pre-pregnancy diabetesa
Yes	1.6	0.9	1.6	1.7	0.7
No	98.2	98.3	98.2	98.2	0.1
Missing	0.2	0.8	0.2	0.1	2.2
Pre-pregnancy hypertensiona
Yes	4.3	2.4	4.3	4.9	2.7
No	95.6	96.8	95.6	95.1	2.3
Missing	0.2	0.8	0.2	0.1	2.2
Previous cesarean deliverya
Yes	12.6	16.1	12.6	12.4	0.5
No	87.3	83.1	87.3	87.5	0.7
Missing	0.2	0.8	0.2	0.1	2.2
Prior poor pregnancy outcomesa
Yes	10.5	6.9	10.5	10.6	0.4
No	89.3	92.3	89.3	89.3	0.1
Missing	0.2	0.8	0.2	0.1	2.2
Smoking before pregnancya
Yes	33.9	24.4	33.9	31.5	5.1
No	62.8	73.8	62.8	66.1	6.8
Missing	3.3	1.8	3.3	2.4	5.2
Woman’s height (inches) a,b	64.4 (3.0)	64.1 (2.9)	64.4 (3.0)	64.4 (2.9)	2.4
Woman’s BMI a
Underweight	9.9	11.3	9.9	9.1	3.0
Healthy	30.4	32.3	30.4	30.1	0.6
Overweight	19.7	23.9	19.7	20.8	2.7
Obese	35.0	24.5	35.0	33.0	4.1
Missing	5.0	8.0	5.0	7.0	8.4
Year of birth or stillbirtha
2011	2.2	12.7	2.2	1.9	2.5
2012	5.0	13.7	5.0	5.5	1.9
2013	12.6	14.5	12.6	12.0	1.9
2014	10.5	14.6	10.5	10.6	0.1
2015	15.1	14.8	15.1	15.7	1.7
2016	24.3	15.0	24.3	24.0	0.6
2017	30.2	14.8	30.3	30.4	0.3
Maternal residencea
Weinland park	10.0	1.3	10.2	7.7	8.8
Near east	11.0	3.2	11.1	12.1	2.9
Franklinton	8.6	5.5	8.6	9.2	2.2
South	11.4	7.6	11.4	12.4	2.9
Linden	8.4	4.1	8.4	8.9	1.6
Southeast	11.1	9.5	11.1	11.7	1.8
Hilltop	4.2	5.6	4.2	3.7	2.1
North	14.7	19.8	14.7	15.6	2.5
Lower riska,e	20.3	43.4	20.3	18.8	3.8
Age of father (years)a,b	29.4 (8.0)	30.7 (7.6)	29.4 (8.0)	29.5 (7.6)	1.2

^aVariable used in building the propensity score model

^bMean (standard deviation); missing data for parity (n = 950); number of living children (n = 963); woman’s height (n = 2148); father’s age (n = 18,688)

^cBirth < 37 completed weeks

^dAfter matching

^eOther Franklin county zip codes

For each pregnancy, the estimated propensity score from each of 10 imputed datasets was averaged across imputations, resulting in one overall estimated propensity score (Kenward and Carpenter 2007; StataCorp 2017). This averaged estimated propensity score was used to match each Moms2B-exposed pregnancy to two unexposed pregnancies, through nearest-neighbor matching without replacement (Stepner and Garland 2017). Propensity score matching was constrained to a caliper distance of 0.05 on the logit scale, just under 5% of the pooled standard deviation of the logit of the propensity score (Austin 2011). Balance between those exposed and unexposed before and after matching was assessed through the absolute standardized difference (ASD), the variance inflation factor, and by graphical diagnostics of propensity score overlap (Austin 2009). To examine the sensitivity of the findings to choice of a propensity score methods approach (i.e., matching versus inverse probability weighting), evaluation of all outcomes was repeated through weighting by the odds of the propensity score (Austin and Stuart 2015).

Outcomes Analysis

The number and proportion of outcomes by exposure group were calculated and the risk difference was estimated through marginal standardization following logistic regression by estimating the relation between each dichotomous outcome and exposure status, accounting for the matched group (Muller and MacLehose 2014). Relative risks were estimated through modified Poisson regression (Zou 2004). Linear regression was used to estimate the difference in continuous outcomes. Standard errors for estimates from all regression models (and their associated 95% confidence intervals) accounted for matching on the propensity score through robust sandwich-type standard errors, which were grouped by the matched set. P-values and 95% confidence intervals are two-sided and presented at the nominal level. All data manipulation and analyses were performed in 2019 in Stata version 15.1 (StataCorp, College Station, TX).

Results

The Moms2B program served 1569 pregnancies from 2010 to 2017. Among these pregnancies, 1327 (85%) were eligible for linkage to 2011–2017 Ohio Vital Records data (Fig. 1). Most of the pregnancies ineligible for linkage involved deliveries outside the study period (n = 139) or were pregnancy losses at < 20 weeks (n = 54). Among those eligible for linkage to vital records, 1210 (91%) were successfully linked. After applying the study inclusion criteria shown in Table 1, 675 singleton pregnancies exposed to Moms2B for the first time (≥ 2 visits during pregnancy) were available for analysis. Among exposed women, their mean gestational age at presentation to Moms2B was 22.4 weeks (SD = 9.2 weeks) and the median number of prenatal sessions attended was 6 (min, max = 2, 33). Exposed pregnancies were closely matched by the propensity score to two unexposed pregnancies (n = 1336). A detailed discussion of the creation of the final analytic file is provided in the online supplement.

Table 2 displays characteristics of the cohort before and after propensity score matching. In the complete cohort, women whose pregnancies were exposed to Moms2B more often exhibited risk factors associated with poor pregnancy outcomes compared to unexposed pregnancies. These risk factors included: being younger, non-Hispanic Black, and unmarried in addition to having a lower educational level, a prior preterm birth, prior poor pregnancy outcomes, pre-existing diabetes and/or hypertension, obesity, and to have smoked prior to pregnancy. This observed difference in risk factors was not surprising as the Moms2B program sites are intentionally located in neighborhoods at high-risk of infant mortality. Although not a risk factor, Moms2B exposed participants were more likely to deliver in 2016 or 2017, as the program has expanded over time.

As discussed previously, propensity score matching was used to ensure balance in measured demographic, social, and health factors between groups. The final propensity score model included all covariates listed in Table 2 and interaction effects between women’s age and race, women’s race and educational attainment, and women’s age and residence, as these interaction effects improved balance overall and by maternal residence and race. Close balance was achieved for all covariates (Table 1); all covariates had an absolute standardized difference < 10% and the distribution of the estimated propensity scores had very tight overlap between exposure groups (eFigure 1).

Following propensity score matching, the data provided some evidence of improved pregnancy outcomes among pregnancies exposed to Moms2B versus unexposed pregnancies, particularly for the outcome of low birth weight (Table 3). Moms2B-exposed pregnancies demonstrated a reduced risk of low birth weight compared to pregnancies that were not exposed [risk difference (RD) = −2.55, 95% confidence interval (CI) = (−5.44, 0.34), p-value = 0.083]; this means Moms2B has the potential to prevent low birth weight in 26 of 1,000 pregnancies within this population on average. While the point estimate suggested a reduction in preterm birth (< 37 weeks) for exposed pregnancies versus unexposed pregnancies, with a risk reduction of −1.74 [95% CI = (−4.76, 1.28), p-value = 0.258], the estimate was highly variable. Examination of secondary outcomes consistently pointed towards a benefit of exposure to Moms2B; confidence intervals were wide for some outcomes, given their rarity [infant mortality: RD = −0.92, 95% CI = (−1.88, 0.04); perinatal death: RD = −0.99, 95% CI = (−2.18, 0.21); stillbirth: RD = −0.31, 95% CI = (−1.30, 0.68); preterm birth < 32 weeks: RD = −0.48, 95% CI = (−1.67, 0.72); pre-term birth < 28 weeks: RD = −0.50, 95% CI = (−1.40, 0.28)]. The mean birth weights and gestational ages at delivery were not different between groups suggesting that differences in low birth weight associated with Moms2B exposure were likely due to subtle shifts in the tails of the birth weight and gestational age distributions. Of note, a sensitivity analysis utilizing inverse probability of treatment weighting (to estimate the average treatment effect on the treated), rather than matching, provided results consistent with the primary analysis (eTable 1) (Austin and Stuart 2015). In particular, risk differences and relative risks were extremely similar while confidence intervals were more precise than those observed in the primary analyses. A second sensitivity analysis (eTable 2) examined the influence of a woman’s birth place (e.g., Ohio, non-Ohio US, not US) as a potential confounder. When this covariate was included in the outcome model results remained extremely consistent with the primary analysis.

Table 3.

Pregnancy outcomes among those exposed to Moms2B versus those not exposed following 1:2 propensity score matching, Moms2B program evaluation, 2011–2017

	Exposed to Moms2B (n = 675) n (%)	Not exposed (n = 1336) n (%)	Risk difference (95% CI)	Relative risk (95% CI)
Preterm birth (< 37 weeks)a	73 (10.9)	167 (12.7)	− 1.74 (− 4.76, 1.28)	0.86 (0.66, 1.12)
Low birth weightb	63 (9.5)	158 (12.0)	− 2.55 (− 5.44, 0.34)e	0.79 (0.59, 1.04)e
Preterm birth (< 32 weeks)a	10 (1.5)	26 (2.0)	− 0.48 (− 1.67, 0.72)	0.76 (0.37, 1.57)
Preterm birth (< 28 weeks)a	4 (0.6)	15 (1.1)	− 0.50 (− 1.40, 0.28)	0.53 (0.17, 1.59)
Stillbirth	7 (1.0)	18 (1.4)	− 0.31 (− 1.30, 0.68)	0.77 (0.32, 1.84)
Perinatal death	9 (1.3)	31 (2.3)	− 0.99 (− 2.18, 0.21)e	0.57 (0.27, 1.21)
Infant mortalitya,c	5 (0.8)	22 (1.7)	− 0.92 (− 1.88, 0.04)e	0.45 (0.17, 1.18)e
Gestational age at delivery (weeks)d	38.3 (2.4)	38.2 (2.8)	0.17 (− 0.08, 0.42)	f
Birth weight (grams)d	3107.2 (609.9)	3081.1 (660.9)	26.14 (− 33.62, 85.90)	f

^aDoes not include stillbirths (n = 7 in Moms2B-exposed group, n = 18 in unexposed)

^bDoes not include stillbirths or one with missing birth weight

^cInfant mortality proportions, not interpretable as infant mortality rates

^dMean (standard deviation)

^eLBW: RD p-value = 0.08, RR p-value = 0.10; Perinatal death: RD p-value = 0.11; Infant mortality: RD p-value = 0.06, RR p-value = 0.11

^fNot applicable

In examining mortality, the data revealed seven stillbirths in the Moms2B exposed group (1.0%) and 18 stillbirths in the unexposed group (1.4%). We identified five infant deaths (0.7%) in the Moms2B exposed group and 22 infant deaths (1.6%) in the unexposed group. The most common causes of death in both groups were extreme prematurity, congenital anomalies, and sleep-related death. The gestational age at delivery for infants who died was later in the Moms2B exposed group (37 weeks) than the unexposed group (34 weeks). Among those infants that died, the median time to death was longer (104 days) for infants born to women who were exposed to Moms2B compared to those not exposed (16 days), most likely due to the reduction in extreme preterm birth among women exposed to Moms2B.

Conclusions for Practice

Using propensity score methods, matching 17 covariates, we found improved pregnancy and infant outcomes among women exposed to Moms2B. The majority (72%) of these women were non-Hispanic Black (Table 2). The evidence was strongest for a reduction in low birth weight. Risk differences and relative risks of all adverse outcomes examined uniformly suggest a protective effect of participation in the program. Given that this evaluation examined rare pregnancy outcomes, the confidence intervals were wide. However, as mentioned previously, this is not uncommon when evaluating nascent public health programs, as analyses are often limited by the sample size of exposed individuals. Our interpretation of the study findings are in line with modern research literature that has de-emphasized null-hypothesis testing, in favor of quantifying uncertainty and effect estimation (Calin-Jageman and Cumming 2019).

Evaluations of public health programs like Moms2B are challenging because (1) the health outcomes of interest are relatively rare and (2) health interventions typically begin with a small number of individuals being exposed. Given the urgent need to identify promising programs to address the most vexing public health problems, such as infant mortality, it is necessary to undertake evaluation after the program is well-established and data have accumulated. This is true even if the total number of individuals exposed to a program is smaller than would traditionally be required to detect differences in rare health outcomes for a randomized trial.

The Moms2B program differs from other mainstream group prenatal care models, such as Centering Pregnancy and Expect with Me, in that the program welcomes women of all gestational ages and those with medically high risk pregnancies (e.g., women who are HIV + , those with pre-existing type 1 diabetes, poorly controlled hypertension, seizure disorder, psychiatric illness, or current substance use), whereas the other programs exclude these women by design (Ickovics et al. 2003). Another key difference between the programs is that Centering Pregnancy and Expect with Me provide prenatal care onsite whereas Moms2B staff act as care coordinators to ensure that women are receiving the individualized care they need from their clinical prenatal care providers, including maternal–fetal medicine specialists.

Our results are notable given that the observed effect of Moms2B on pregnancy outcomes is in line with those reported for other group prenatal care models despite Moms2B’s inclusion of high-risk pregnancies. While two recent meta-analyses of randomized controlled trials (RCTs) reported no differences in pregnancy outcomes among women exposed to group prenatal care versus individual care, several trials in the U.S. have suggested a benefit of group prenatal care in specific subpopulations (Carter et al. 2016; Catling et al. 2015). Ickovics and colleagues conducted a RCT in which women, mostly non-Hispanic Black or Latina, aged 14–25 years were randomized to Centering Pregnancy (n = 623) or individual prenatal care (n = 370) (Ickovics et al. 2007). They reported a lower rate of preterm birth < 37 weeks (9.8%) in the intervention group compared to those assigned to individual prenatal care (13.8%) but no differences in other outcomes. The same group completed a cluster RCT of Centering Pregnancy coupled with comprehensive reproductive health education (Ickovics et al. 2016). Using an intent-to-treat approach, the investigators found a 34% reduction in the odds of small for gestational age in the intervention group (n = 573) compared to individual care (n = 575). Using an as-treated analysis, they reported a reduced odds of preterm birth, low birth weight, and small for gestational age. Cunningham and colleagues applied propensity score methods to examine the impact of exposure to Centering Pregnancy or Expect with me on pregnancy outcomes with only 28% of the study population being Black (Cunningham et al. 2019). Women who participated in either group model (n = 1384) had a 37% reduction in the risk of preterm birth and a 38% reduction in the risk of low birth weight compared to women who received only individual care (n = 5055).

While there are similarities between the Moms2B group model and other group prenatal care models, the Moms2B program has unique features. A summary of the characteristics of Centering Pregnancy versus Moms2B can be found elsewhere (Gabbe et al. 2018). Our findings suggest that the Moms2B program is effective; however, the specific drivers of the improvement are unclear. One possibility is that the Moms2B program provides social support to women not only by building trusting relationships with them over time but also by introducing them to other women in their neighborhood. Social support is the only factor consistently shown to mitigate the impact of stress during pregnancy (Grobman et al. 2018). Another possible explanation is that the weekly health and wellness education topics inspire women to make positive changes in their health habits. Further, perhaps the assistance team members provide, in terms of linking women to clinical and social services, is beneficial.

The current study has many strengths. First, we were able to examine the pregnancy outcomes of a large group of women, most of whom were non-Hispanic Black, exposed to an innovative neighborhood-based group model of prenatal and parenting support. We used propensity score methods to identify women not exposed to the program who were closely matched to exposed women on demographic and clinical factors, allowing comparison of important pregnancy outcomes. Moreover, sensitivity analyses were consistent with the primary results, suggesting that our findings are robust to the choice of analytic method. All pregnancy outcomes included in this analysis were obtained through a link to Ohio Vital Records. Relatively few pregnancies (n = 117, 9%) could not be linked or were lost to follow-up. Moms2B attendance data used were prospectively recorded by program staff over the years rather than being retrospectively reported.

Several limitations should be noted. While all probabilistic matches were manually verified, there remains the possibility that linkage errors occurred. Further, we caution over interpretation of findings from secondary outcomes, due to the potential for inflation of false positive findings as a result of multiple comparisons and the relatively small number of events. Longer follow-up will be needed to verify these results. In Ohio, fetal death reporting is only required for deaths occurring at 20 weeks of gestation or later; therefore, we could not examine early fetal deaths. Finally, the current work does not explore the benefits of repeated exposure in subsequent pregnancies to the program, which warrants consideration in future analyses.

Our findings suggest that participation in the Moms2B program improves pregnancy and infant outcomes in women at increased risk for experiencing infant mortality. Given the high rates of both infant and maternal mortality in the U.S., there is an urgent need for innovation in the way we deliver healthcare to women. These enhancements to traditional prenatal care offered by the Moms2B program hold promise for improving pregnancy outcomes and reducing infant mortality and its associated racial disparities.

Significance Statement.

What is already known:

Traditional biomedical models of prenatal care have failed to eliminate disparities in pregnancy outcomes. Alternative models of prenatal care that address the social determinants of health, in addition to biomedical factors, are needed.

What this study adds:

Moms2B, an innovative group pregnancy and parenting support program, has improved pregnancy outcomes among urban neighborhoods with high rates of infant mortality. The community-based program offers prenatal and parenting education in a group setting while providing women one-on-one support from pregnancy through their infants’ first year of life.