Among the 6,207 children in the ROC-Cohort, 44 were stillbirths and excluded from the analysis. Stillbirth was not associated with violence exposure during pregnancy in our sample (0.99; 95%CI: 0.92–1.06). Additionally, 895 mother-child dyads were excluded due to an invalid address. Overall, 5,268 children and their mothers met the inclusion criteria for this study. Mothers who did not respond to the postpartum questionnaire did not differ from those who completed the survey regarding the type of birth, gestational length category, birth weight and length, and child sex.
398 (7.8%) births were classified as SGA, 369 (7.0%) as PT, and 355 (6.7%) as LBW. Table 1 shows the frequency of each type of crime during pregnancy by exposure quintile. During the first two trimesters, the mean number of crimes exposition within a 1-kilometer from home was 4.2 (SD ± 4.8). The large majority of violent crimes were classified as murders; death resulting from policy intervention was the second most common type of violent crime. Women with the lowest exposure in the sample (quintile 1) were exposed to 0.45 (SD ± 0.5) violent crimes on average. Only 19% of women did not experience any exposition to violent crimes in their vicinity during the first two trimesters. In the fifth quintile, women were exposed on average to 12.7 (SD ± 4.5) violent crimes, with some women experiencing more than 30 violent crimes during the first two trimesters.
Table 1
Frequency of violent crime type in pregnancy per exposure quintile.
| 1st quintile | 2nd quintile | 3rd quintile | 4th quintile | 5th quintile |
Murder | 0.39 ± 0.49 | 1.71 ± 0.67 | 2.64 ± 0.71 | 4.34 ± 1.38 | 9.08 ± 2.85 |
Assault followed by death | 0.26 ± 0.65 | 0.26 ± 0.65 | 0.29 ± 0.65 | 0.48 ± 0.90 | 0.65 ± 1.50 |
Bodily injury followed by death | 0.01 ± 0.08 | 0.02 ± 0.12 | 0.01 ± 0.10 | 0 | 0 |
Death resulting from police intervention | 0 | 0.01 ± 0.16 | 0.06 ± 0.34 | 0.22 ± 0.64 | 3.02 ± 2.79 |
Figure 1 shows the geographic distribution of the outcomes and violent crimes in the studied area. Areas colored in red represent the highest crime exposure; blue areas are safest. Panel A of Figure one shows the overall spatial distribution of children in the study area. Panels B, C, and D illustrate the spatial distribution of the three adverse birth outcomes
Areas on the first, third, and fifth quintile of violent crimes had 6.7%, 7.9%, and 9.5% of SGA children, 6.5%, 6.4%, and 6.3% of PT, and 5.4%, 7% and 7.5% of born LBW children, respectively. Table 2 shows the distribution of SGA, PT, and LBW birth outcomes by exposure quintile. In bivariate analysis, LBW was strongly associated with crime exposure (1.09; 95%CI: 1.02–1.17, p = 0.014), while PT and SGA displayed positive but not statistically significant associations with violent crimes. Upper middle (0.91; 95%CI: 0.85–0.98, p = 0.013) and high (0.83; 95%CI: 0.77–0.89, p < 0.001) SES status were negatively associated with violent crimes. Physical abuse was also negatively associated with violence (0.79; 95%CI: 0.66–0.95, p = 0.013).
Table 2
Birth outcomes and child and family characteristics by external violence exposure quintile.
Violent crimes quintile Number of occurrences | 1st quintile Low: 0–1 | | 3rd quintile Medium: 3 | | 5th quintile High: 8–37 | OR (95%CI) | p |
| n | % | | N | % | | n | % | | |
SGA (N = 5,080) | | | | | | | | | | |
Yes | 116 | 6.7 | | 36 | 7.9 | | 87 | 9.5 | 1.06 (1.00-1.14) | 0.062 |
PT (N = 5,268) | | | | | | | | | | |
Yes | 116 | 6.5 | | 30 | 6.4 | | 61 | 6.3 | 1.02 (0.95–1.09) | 0.594 |
LBW (N = 5,268) | | | | | | | | | | |
Yes | 96 | 5.4 | | 33 | 7.0 | | 72 | 7.5 | 1.09 (1.02–1.17) | 0.014 |
Fetal sex (N = 5,268) | | | | | | | | | | |
Female | 898 | 50.2 | | 246 | 52.1 | | 469 | 48.7 | 1.00 (0.96–1.03) | 0.937 |
Maternal age (N = 5,268) | | | | | | | | | | |
< 20 years | 381 | 21.3 | | 93 | 19.7 | | 239 | 24.8 | 1.03 (0.99–1.07) | 0.157 |
20–35 years | 1191 | 66.6 | | 327 | 69.5 | | 626 | 64.9 | | Ref. |
> 35 years | 216 | 12.1 | | 52 | 11.0 | | 99 | 10.3 | 0.96 (0.90–1.01) | 0.125 |
Skin color (N = 5,267) | | | | | | | | | | |
White | 1080 | 60.4 | | 286 | 60.7 | | 593 | 61.5 | | Ref. |
Non-white | 707 | 39.6 | | 186 | 39.4 | | 371 | 38.5 | 1.00 (0.96–1.03) | 0.888 |
SES status (N = 2,709) | | | | | | | | | | |
Low | 144 | 16.0 | | 45 | 18.0 | | 128 | 24.6 | 1.08 (1.00-1.16) | 0.045 |
Lower middle | 225 | 25.1 | | 66 | 27.9 | | 156 | 30.0 | | Ref. |
Middle | 126 | 14.0 | | 40 | 16.9 | | 79 | 15.2 | 0.98 (0.91–1.06) | 0.605 |
Upper Middle | 213 | 23.7 | | 91 | 20.3 | | 104 | 20.0 | 0.91 (0.85–0.98) | 0.013 |
High | 190 | 21.2 | | 79 | 16.0 | | 53 | 10.2 | 0.83 (0.80–0.89) | < 0.001 |
Education (N = 3,256) | | | | | | | | | | |
Incomplete primary | 154 | 13.2 | | 44 | 15.8 | | 109 | 18.9 | 1.07 (1.01–1.14) | 0.026 |
Complete secondary | 934 | 80.0 | | 216 | 77.7 | | 452 | 78.5 | | Ref. |
Tertiary | 79 | 6.8 | | 18 | 6.5 | | 15 | 2.6 | 0.83 (0.13–0.19) | < 0.001 |
Diabetes (N = 3,246) | | | | | | | | | | |
Yes | 36 | 3.1 | | 6 | 2.2 | | 16 | 2.8 | 0.95 (0.83–1.09) | 0.500 |
Hypertension (N = 3,249) | | | | | | | | | | |
Yes | 130 | 11.2 | | 21 | 7.6 | | 51 | 8.9 | 0.95 (0.88–1.03) | 0.189 |
Smoke in pregnancy (N = 3,240) | | | | | | | | | | |
Yes | 161 | 14.0 | | 37 | 13.3 | | 83 | 14.4 | 0.99 (0.93–1.06) | 0.802 |
Drink in pregnancy (N = 3,245) | | | | | | | | | | |
Yes | 161 | 13.9 | | 40 | 14.4 | | 66 | 11.4 | 0.94 (0.88–1.01) | 0.079 |
Depression (N = 3,251) | | | | | | | | | | |
Yes | 34 | 2.9 | | 3 | 1.1 | | 9 | 1.6 | 0.93 (0.81–1.07) | 0.329 |
Physical abuse (N = 3,236) | | | | | | | | | | |
Yes | 27 | 2.3 | | 4 | 1.5 | | 7 | 1.2 | 0.79 (0.66–0.95) | 0.013 |
Quintiles categorized violent crimes within a 1−kilometer from participants’ home address; OR: odds ratio; 95% CI: 95% confidence interval; SGA: small for gestational age; PT preterm; LBW: low birth weight; SES: socioeconomic status. |
Figure 2 shows the bivariate relationship between exposure to violent crime and the proportion of infants born SGA (panel a), preterm (panel b) and LBW (panel c). Table 3 shows the unadjusted and adjusted associations between violent crime exposure during pregnancy and adverse birth outcomes. Relative to children from the lowest violence quintile, living in the highest violence quintile was associated with a 46% increase in the odds of SGA in the unadjusted model (1.46; 95%CI: 1.10–1.93). After adjustment for covariates, risk factors and SES status, the estimated odds ratio (OR) slightly decreased (1.41; 95%CI: 1.06–1.89). In the adjusted model, PT birth odds increased nonlinearly (Fig. 2) with violence exposure, varying the estimated ORs from 1.16 (95%CI: 0.84–1.59) on quintile 2, 1.35 (95%CI: 1.01–1.80) on quintile 4, and 1.01 (95%CI: 0.72–1.40) on quintile 5. The estimated risk of LBW increased almost linearly with exposure quintiles, with an estimated OR of 1.43 (95%CI: 1.03–1.98) for the top quintile. In terms of the included covariates, smoking during pregnancy was the most consistent risk factor for all birth outcomes analyzed in this study, with estimated ORs of 1.83 for SGA (95%CI: 1.32–2.55), 2.04 for PT birth (95%CI: 1.47–2.82), and 2.89 for LBW (95%CI: 2.07–4.03). Physical abuse during pregnancy more than doubled the odds for LBW (2.12; 95%CI: 1.03–4.36, p = 0.042). SES and maternal education were not associated with the outcomes in our analysis.
Table 3
Unadjusted and adjusted analyses between violent crimes exposure during pregnancy by quintiles, and birth outcomes.
| Unadjusted | | | Adjusted* | |
| OR | 95%IC | P | | OR | 95%IC | p |
Small-for-gestational-age | | | | | | | |
Violent crimes | | | | | | | |
1st quintile | Ref. |
2nd quintile | 1.36 | 1.02–1.83 | 0.039 | | 1.34 | 1.00-1.80 | 0.054 |
3rd quintile | 1.20 | 0.82–1.75 | 0.349 | | 1.19 | 0.81–1.75 | 0.373 |
4th quintile | 1.12 | 0.84–1.50 | 0.418 | | 1.11 | 0.84–1.50 | 0.449 |
5th quintile | 1.46 | 1.10–1.93 | 0.009 | | 1.41 | 1.06–1.89 | 0.019 |
Physical abuse | | | | | 1.07 | 0.43–2.65 | 0.896 |
Depression | | | | | 0.42 | 0.13–1.36 | 0.147 |
Diabetes | | | | | 0.70 | 0.27–1.82 | 0.468 |
Hypertension | | | | | 1.27 | 0.82–1.95 | 0.286 |
Smoke | | | | | 1.83 | 1.32–2.55 | < 0.001 |
Drink | | | | | 1.43 | 0.99–2.05 | 0.055 |
Preterm birth | | | | | | | |
Violent crimes | | | | | | | |
1st quintile | Ref. |
2nd quintile | 1.17 | 0.86–1.59 | 0.327 | | 1.16 | 0.84–1.59 | 0.367 |
3rd quintile | 0.98 | 0.65–1.48 | 0.918 | | 1.01 | 0.66–1.54 | 0.958 |
4th quintile | 1.29 | 0.98–1.72 | 0.070 | | 1.35 | 1.01–1.80 | 0.040 |
5th quintile | 0.97 | 0.71–1.34 | 0.870 | | 1.01 | 0.72–1.40 | 0.969 |
Physical abuse | | | | | 1.62 | 0.77–3.44 | 0.206 |
Depression | | | | | 0.81 | 0.32–2.08 | 0.662 |
Diabetes | | | | | 0.94 | 0.39–2.23 | 0.884 |
Hypertension | | | | | 1.21 | 0.76–1.91 | 0.425 |
Smoke | | | | | 2.04 | 1.47–2.82 | < 0.001 |
Drink | | | | | 1.18 | 0.79–1.76 | 0.420 |
Low birth weight | | | | | | | |
Violent crimes | | | | | | | |
1st quintile | Ref. |
2nd quintile | 1.38 | 1.00-1.91 | 0.050 | | 1.37 | 0.98–1.91 | 0.063 |
3rd quintile | 1.32 | 0.88–1.99 | 0.178 | | 1.36 | 0.89–2.07 | 0.153 |
4th quintile | 1.48 | 1.10–1.99 | 0.010 | | 1.50 | 1.11–2.05 | 0.009 |
5th quintile | 1.42 | 1.04–1.95 | 0.029 | | 1.42 | 1.03–1.98 | 0.034 |
Physical abuse | | | | | 2.12 | 1.03–4.36 | 0.042 |
Depression | | | | | 0.71 | 0.22–2.25 | 0.557 |
Diabetes | | | | | 0.30 | 0.07–1.30 | 0.107 |
Hypertension | | | | | 1.73 | 1.10–2.71 | 0.017 |
Smoke | | | | | 2.89 | 2.07–4.03 | < 0.001 |
Drink | | | | | 1.14 | 0.77–1.69 | 0.522 |
OR: odds ratio; 95% CI: 95% confidence interval; All analyses used multiple imputations. Imputed data were averaged across the 50 imputed data sets using Rubin’s rule [41]. *Adjusted for maternal age, child sex (female), education, and socioeconomic status.