Table 1.
Study sample characteristics of those with experience of trauma in their lifetime and the unexposed control.
| Sample characteristics | ||||
| Characteristic | No experience of trauma | Lifetime trauma experience | Pearson's chi-squared test | Total |
| n=309 (68.21%) | n=144 (31.79%) | χ2(df, n) | n=453 | |
| n (%) | n (%) | p-value | n (%) | |
| Maternal Age (years old)* | ||||
| <20 | 0 (0.00) | 4 (2.78) | χ2=13.90 | 4 (0.88) |
| 20-29 | 72 (23.30) | 47 (32.64) | (3, n=453) | 119 (26.27) |
| 30-39 | 214 (69.26) | 83 (57.64) | p=0.003 | 297 (65.56) |
| ≥40 | 23 (7.44) | 10 (6.94) | 33 (7.28) | |
| Ethnicity | ||||
| White | 179 (57.93) | 72 (50.00) | 251 (55.41) | |
| Black African/Caribbean or black British | 88 (24.48) | 49 (34.03) | χ2=7.40 | 137 (30.24) |
| Asian/Asian British | 13 (4.21) | 6 (4.17) | (4, n=453) | 19 (4.19) |
| Mixed/Multiple ethnic groups | 8 (2.59) | 10 (6.94) | p=0.116 | 18 (3.97) |
| Arab/Other ethnicity | 21 (6.80) | 7 (4.86) | 28 (6.18) | |
| Education (highest level achieved)* | ||||
| None/School qualifications | 26 (8.41) | 20 (13.89) | χ2=8.27 | 46 (10.15) |
| College/Diploma/Higher certificate/Training | 103 (33.33) | 60 (41.67) | (2, n=453) | 163 (35.98) |
| University degree/Postgraduate | 180 (58.25) | 64 (44.44) | p=0.016 | 244 (53.86) |
| Employment* | ||||
| Employed/Homemaker/Student | 268 (87.01) | 104 (72.73) | χ2=13.79 | 372 (82.48) |
| (1, n=451) | ||||
| Unemployed/Unable to work | 40 (12.99) | 39 (27.27) | p<0.001 | 79 (17.52) |
| Household income* | ||||
| <£15,000 | 26 (10.70) | 31 (27.19) | 57 (15.97) | |
| £15,000 - £30,999 | 36 (14.81) | 22 (19.30) | χ2=22.76 | 58 (16.25) |
| £31,000 - £45,999 | 45 (18.52) | 9 (7.89) | (4, n=357) | 54 (15.13) |
| £46,000 – £60,999 | 38 (15.64) | 19 (16.68) | p<0.001 | 57 (15.97) |
| £61,000 or more | 98 (40.33) | 33 (28.95) | 131 (36.69) | |
| Relationship status* | ||||
| In a relationshipa | 284 (91.91) | 117 (81.25) | χ2=10.98 | 401 (88.52) |
| (1, n=453) | ||||
| Single | 25 (8.09) | 27 (18.75) | p=0.001 | 52 (11.48) |
| Currently living with* | ||||
| Alone | 30 (9.71) | 25 (17.73) | 55 (12.22) | |
| Spouse/Partner | 247 (79.94) | 78 (55.32) | χ2=41.47 | 325 (72.22) |
| Parent(s) | 3 (0.97) | 6 (4.26) | (6, n=450) | 9 (2.00) |
| Friends | 7 (2.27) | 2 (1.42) | p<0.001 | 9 (2.00) |
| Other family members | 13 (4.21) | 9 (6.38) | 22 (4.89) | |
| Acquaintance | 0 (0.00) | 2 (1.42) | 2 (0.44) | |
| Other | 9 (2.91) | 19 (13.48) | 28 (6.22) | |
| Any previous children | ||||
| Yes | 159 (51.46) | 72 (50.00) | χ2=0.08 | 231 (50.99) |
| (1, n=453) | ||||
| No | 150 (48.54) | 72 (50.00) | p=0.773 | 222 (49.01) |
| Previous miscarriage* | ||||
| No | 230 (74.43) | 86 (59.72) | χ2=10.08 | 316 (69.76) |
| (1, n=453) | ||||
| Yes | 79 (25.57) | 58 (40.28) | p=0.002 | 137 (30.24) |
| Gender of infant | ||||
| Female | 154 (50.00) | 71 (49.31) | χ2=0.02 | 225 (49.78) |
| (1, n=452) | ||||
| Male | 154 (50.00) | 73 (50.69) | p=0.891 | 227 (50.22) |
| Infant GA at birth (in weeks) | ||||
| Born at term (≥37) | 288 (93.51) | 137 (95.14) | χ2=0.47 | 425 (94.03) |
| (1, n=452) | ||||
| Prematurely born (<37) | 20 (6.49) | 7 (4.86) | p=0.495 | 27 (5.97) |
| Mean GA at birth ±SD (95% CI) | 39.21 ±2.03 (38.98–39.43) | 39.10 ±2.10 (38.76–39.45) | WMWp=0.276 | 39.18 ±2.05 |
| T-testp=0.606 | (38.99 – 39.37) | |||
| Pregnancy planned or unplanned* | ||||
| Planned | 224 (72.49) | 82 (56.94) | χ2=10.83 | 306 (67.55) |
| (1, n=453) | ||||
| Unplanned | 85 (27.51) | 62 (43.06) | p=0.001 | 147 (32.45) |
| EPDS* | ||||
| Low symptoms (<13) | 249 (83.56) | 85 (59.44) | χ2=30.58 | 334 (75.74) |
| (1, n=441) | ||||
| High symptoms (≥13 and including) | 49 (16.44) | 58 (40.56) | p<0.001 | 107 (24.26) |
| Mean EPDS score ±SD (95% CI) | 7.35 ±5.54 (6.72 – 7.98) | 10.85 ±6.61 (9.75–11.94) | WMWp<0.001 | 8.49 ±6.12 |
| T-testp<0.001 | (7.91 – 9.06) | |||
| PDS®* | ||||
| Mean PDS®score ±SD (95% CI) | 1.72 ±5.14 (1.14–2.32) | 8.20 ±11.41 (6.25–10.14) | WMWp<0.001 | 3.77 ±8.24 |
| T-test p<0.001 | (2.98 – 4.55) | |||
Pearson's chi-squared test was used to assess for population differences for categorical characteristics and Wilcoxon-Mann-Whitney test and t-test for continuous characteristics. The statistical tests used for continuous data have been highlighted in bold, with data presented in italics.
Note: EPDS, Edinburgh postpartum bonding questionnaire. GA, gestational age. PBQ, postpartum bonding questionnaire. PDS®, Posttraumatic Stress Disorder Scale. SD, standard deviation. df, degrees of freedom. WMW, Wilcoxon-Mann-Whitney test. 95% CI, 95% confidence interval.
* p-value <0.05 thus significant difference between lifetime trauma experience and unexposed control.
a. In a relationship = In a relationship, cohabiting or married.