Table 2.
Study Characteristics of Participants Exposed and Unexposed to Nonsteroidal Anti-Inflammatory Drugs
Salicyclates included products with aspirin as an active ingredient as well as those that include aspirin and other medications as well as diflunisal, disalcid, and trilisate; acetic acids included Indomethacin, diclofenac, alclofenac, fenoclofenac, tolmetin, etodolac, sulindac; proprionic acid derivatives included Ibuprofen, naproxen, ketoprofen, fenoprofen, flubiprofen, suprofen, oxaprozin; enolic acid derivatives included piroxicams, tenoxicams, isoxicams, and meloxicams. Participants could have reported more than one NSAID and therefore could be included in more than one NSAID class. As a result total percentages across classes do not sum to 100%. Percentages represent total N for NSAID class divided by total number of NSAIDs by status.
| Variable | NSAID Use (n =1,185) | No NSAID Use (n =1,595) |
|---|---|---|
| Maternal age (mean yrs ± SD) | 29.7±4.6 | 29.6±4.8 |
| Gravidity | ||
| 1 | 472 (40%) | 532 (33%) |
| More than 1 | 713 (60%) | 1,063 (67%) |
| Parity | ||
| 0 | 601 (53%) | 706 (46%) |
| 1 or more | 526 (47%) | 840 (54%) |
| Body mass index (mean ± SD) | 25.7±6.1 | 25.4±5.9 |
| Underweight (less than 20) | 90 (8%) | 150 (10%) |
| Normal weight (20 or higher to 26) | 672 (58%) | 913 (58%) |
| Overweight (higher than 26 to 29 or lower) | 153 (13%) | 198 (13%) |
| Obese (higher than 29 and above) | 254 (22%) | 304 (19%) |
| Maternal race or ethnicity | ||
| Caucasian | 945 (80%) | 1,240 (78%) |
| African American | 124 (11%) | 184 (12%) |
| Hispanic | 63 (5%) | 82 (5%) |
| Other | 52 (4%) | 86 (5%) |
| Household income | ||
| $40,000 or lower | 436 (22%) | 599 (23%) |
| $40,001–$80,000 | 244 (40%) | 348 (40%) |
| Higher than $80,000 | 419 (38%) | 556 (37%) |
| Marital status | ||
| Married or cohabitating | 1,109 (94%) | 1,499 (94%) |
| Other | 76 (6%) | 96 (6%) |
| History of preterm birth | ||
| 0 | 1,050 (93%) | 1,423 (92%) |
| 1 or more | 77 (7%) | 123 (8%) |
| History of spontaneous abortions | ||
| 0 | 895 (79%) | 1,163 (75%) |
| 1 or more | 232 (21%) | 383 (25%) |
| History of induced abortions | ||
| 0 | 980 (87%) | 1,368 (88%) |
| 1 or more | 147 (13%) | 178 (12%) |
| Smoking status | ||
| Nonsmokers | 1,093 (97%) | 1,509 (98%) |
| Current | 31 (3%) | 34 (2%) |
| Diabetes | ||
| None | 1,102 (98%) | 1,498 (97%) |
| Any | 22 (2%) | 45 (3%) |
| Study site | ||
| North Carolina | 806 (68%) | 1,174 (74%) |
| Tennessee | 373 (31%) | 415 (26%) |
| Texas | 6 (1%) | 6 (<1%) |
NSAID, nonsteroidal anti-inflammatory drugs; SD, standard deviation;
Data are mean ± standard deviation and frequency in counts (n[%]).