Table II.
Baseline and time-varying pain medication use during the past 4 weeks and fecundability among female pregnancy planners.
| Exposure | Baseline analysis | Time-varying analysis | ||||||
|---|---|---|---|---|---|---|---|---|
| No. of cycles | No. of Pregs | Unadjusted FR (95% CI) | Adjusted FR (95% CI)a | No. of cycles | No. of Pregs | Unadjusted FR (95% CI) | Adjusted FR (95% CI)a | |
| Non-use | 2158 | 308 | Reference | Reference | 2400 | 334 | Reference | Reference |
| Any use | 5830 | 820 | 1.01 (0.90–1.14) | 1.04 (0.92–1.18) | 5588 | 784 | 1.00 (0.89–1.13) | 1.03 (0.92–1.17) |
| Acetaminophen | 2362 | 338 | 1.04 (0.92–1.18) | 1.04 (0.92–1.18) | 2377 | 340 | 1.04 (0.92–1.18) | 1.03 (0.91–1.17) |
| Aspirin | 577 | 78 | 1.01 (0.81–1.26) | 1.00 (0.80–1.25) | 547 | 75 | 0.99 (0.79–1.24) | 0.97 (0.78–1.21) |
| Ibuprofen | 3995 | 559 | 0.98 (0.88–1.09) | 1.00 (0.89–1.11) | 3673 | 521 | 0.97 (0.87–1.08) | 0.99 (0.88–1.10) |
| Naproxen | 840 | 86 | 0.75 (0.61–0.93) | 0.78 (0.64–0.97) | 781 | 75 | 0.68 (0.55–0.85) | 0.71 (0.57–0.89) |
| Opioids | 369 | 41 | 0.81 (0.60–1.09) | 0.81 (0.60–1.10) | 334 | 35 | 0.76 (0.55–1.05) | 0.79 (0.57–1.09) |
FR, fecundability ratio; Pregs, pregnancies. Specific medication categories are not mutually exclusive. Medication-specific results are additionally adjusted for each of the other pain medications.
aAdjusted for age, education, income, race/ethnicity, IUD or OCs as last method of contraception, BMI, smoking history, physical activity, intercourse frequency, history of spontaneous abortion, having irregular menstrual cycles, menstrual cycle length, pain severity during menses, doing something to improve chances of conceiving, diagnosis of anxiety, endometriosis, leiomyomata, migraine headaches and antibiotic use.