Table 1. Maternal Characteristics Stratified by Use of Benzodiazepines or Z-Hypnotics During Pregnancy.
| Variable | Benzodiazepine or z-hypnotic exposure during pregnancy, No. (%) | |
|---|---|---|
| Yes (n = 679) | No (n = 81 359) | |
| Age, mean (SD), y | 31.2 (4.8) | 30.2 (4.5) |
| Married or cohabiting with father | 614 (90.4) | 78 483 (96.5) |
| Primiparous | 356 (52.4) | 37 285 (45.8) |
| Prepregnancy BMI, mean (SD) | 23.7 (4.2) | 24 (4.2) |
| Missing | 13 (1.9) | 1979 (2.4) |
| College or university educationa | 239 (35.2) | 27 847 (34.2) |
| Missing | <5 | 343 (0.4) |
| Smoking | 112 (16.5) | 6061 (7.4) |
| Missing | <5 | 1062 (1.3) |
| Alcohol intake during pregnancyb | ||
| None or minimal | 510 (75.1) | 72 565 (89.2) |
| Low to moderate | 28 (4.1) | 2050 (2.5) |
| Frequent | <5 | 70 (0.1) |
| Missing | 64 (9.4) | 6675 (8.2) |
| Gross yearly income, $ | ||
| ≤17 500 | 71 (10.5) | 7785 (9.6) |
| 17 501-46 800 | 510 (75.1) | 62 157 (76.4) |
| >46 800 | 76 (11.2) | 8825 (10.8) |
| Missing | 22 (3.2) | 2592 (3.2) |
| Planned pregnancy | 189 (27.8) | 66 691 (82.0) |
| Missing | <5 | 115 (0.1) |
| Folic acid supplementationc | 279 (41.1) | 32 190 (39.6) |
| Illicit drug usedd | 33 (4.9) | 468 (0.6) |
| Lifetime history of major depression | 134 (19.7) | 4672 (5.7) |
| Missing | 20 (2.9) | 1992 (2.4) |
| Sleeping problems | 293 (43.2) | 12 721 (15.6) |
| Anxiety | 185 (27.2) | 2710 (3.3) |
| Depression | 211 (31.1) | 5328 (6.5) |
| Adverse life event | ||
| No | 154 (22.7) | 32 843 (40.4) |
| ≥1, not painful | 138 (20.3) | 20 139 (24.8) |
| ≥1, painful or very painful | 387 (57.0) | 28 377 (34.9) |
| Comedications anytime during pregnancy | ||
| Nonsteroidal anti-inflammatory | 98 (14.4) | 5027 (6.2) |
| Opioids | 97 (14.3) | 1637 (2.0) |
| Paracetamol | 443 (65.2) | 36 666 (45.1) |
| Antidepressants | 110 (16.2) | 781 (1.0) |
| Antipsychotics | 43 (6.3) | 623 (0.8) |
| Antiepileptics | 12 (1.8) | 264 (0.3) |
| Depressive or anxiety symptoms during pregnancy, z score (SD) | ||
| SCL-5 at week 17 | 0.89 (1.7) | −0.01 (0.99) |
| Missing | 32 (4.7) | 2589 (3.2) |
| SCL-8 at week 30 | 0.97 (1.7) | −0.01 (0.99) |
| Missing | 60 (8.8) | 6160 (7.6) |
Abbreviations: BMI, body mass index (calculated as weight in kilograms divided by height in meters squared); SCL-5, the Hopkins Symptoms Checklist 5; SCL-8, the Hopkins Symptoms Checklist 8; z-hypnotics, benzodiazepine-like hypnotic drugs.
a
Highest level of either completed or ongoing education.
b
No or minimal alcohol intake indicates less than 1 alcoholic drink per month; low to moderate alcohol intake, 1 alcoholic drink per month to 1 alcoholic drink per week; frequent alcohol intake, more than 1 alcoholic drink per week.
c
Folic acid supplementation in the 4 weeks before pregnancy or up to week 12 of pregnancy.
d
Illicit drug use during pregnancy or the last month before pregnancy.