Table 2.
Frequencies and adjusted odds ratios for small-for-gestational-age birth by antenatal model of care and psychosocial risk characteristics, British Columbia, April 1, 2008-December 31, 2012
| Small-for-gestational-age birth by model of care | ||||||
|---|---|---|---|---|---|---|
| MW n = 3391 | GP n = 25,733 | OB n = 4742 | MW vs. GP | MW vs. OB | GP vs. OB | |
| n(%) | n(%) | n(%) | aOR (95% CI) | aOR (95% CI) | aOR (95% CI) | |
| Mental illnessa | ||||||
| Yes | 42/1011 (4.15) | 340/4912 (6.92) | 45/545 (8.26) | 0.64 (0.46–0.89) | 0.49 (0.32–0.77) | 0.77 (0.55–1.08) |
| No | 129/2380 (5.42) | 1461/20,821 (7.02) | 361/4197 (8.60) | 0.76 (0.63–0.92) | 0.63 (0.51–0.78) | 0.83 (0.73–0.94) |
| Substance useb | ||||||
| Yes | 6/152 (3.95) | 222/2275 (9.76) | 23/182 (12.64) | 0.41 (0.18–0.93) | 0.31 (0.12–0.78) | 0.75 (0.46–1.21) |
| No | 165/3239 (5.09) | 1579/23,458 (6.73) | 383/4560 (8.40) | 0.75 (0.63–0.89) | 0.62 (0.51–0.75) | 0.83 (0.73–0.94) |
| Teen mother | ||||||
| Yes (14–19 yrs.) | 8/117 (6.84) | 181/2582 (7.01) | 21/205 (10.24) | 0.94 (0.45–1.98) | 0.56 (0.24–1.34) | 0.60 (0.36–0.99) |
| No (25–29 yrs.) | 55/1159 (4.75) | 537/7697 (6.98) | 126/1370 (9.20) | 0.71 (0.53–0.94) | 0.55 (0.39–0.76) | 0.78 (0.63–0.96) |
| Mental illness, substance use | ||||||
| Both | 5 or less /95c | 90/927 (9.71) | 10/76 (13.16) | 0.33 (0.10–1.07) | 0.22 (0.06–0.87) | 0.68 (0.32–1.43) |
| Neither | 126/2322 (5.43) | 1324/19,424 (6.82) | 348/4086 (8.52) | 0.78 (0.64–0.94) | 0.64 (0.51–0.79) | 0.82 (0.72–0.94) |
Abbreviations: MW midwife, GP general practitioner, OB obstetrician, OR odds ratio, CI confidence interval
aMental illness included any of the following diagnoses prior to, or during the current pregnancy: anxiety disorder, depression, postpartum depression, bipolar disorder, other/unknown (including schizophrenic, mood, and psychotic disorders). Aside from mild anxiety or depression, a physician would diagnose mental illness
bSubstance use included any indication in the medical record of heroin/opioids, cocaine, methadone, solvents, marijuana or other/unknown drugs used by the mother at any time during pregnancy, as well as prescription or other drug use identified as a risk by the provider
cPercentage suppressed due to small cell size
*Outcomes had statistically significant tests of interaction (p < 0.10) comparing difference of effect across strata (yes vs. no)
Models adjusted for all variables listed except stratifying variables: maternal age, parity, pre-pregnancy BMI, infant sex, smoking status, substance use, mental illness/disorder, and Local Health Area (LHA) socioeconomic rank
Odds ratios based on 2378 births with SGA and 33,866 total births with no missing information for this analysis