Table 2.
Associations between analgesic medication use at three specific time points of the menstrual cycle and fecundability in the Time to Conceive cohort, 2008–2016
| Time windows | N of cyclesa | N of conceptions | Medications | Minimally adjusted FR b (95% CI) | Fully adjusted FRc (95% CI) |
|---|---|---|---|---|---|
| Pre-ovulatory | 146 | 35 | Acetaminophen | 1.08 (0.77, 1.51) | 1.02 (0.73, 1.44) |
| 26 | 6 | Aspirin | 1.15 (0.57, 2.32) | 1.05 (0.53, 2.09) | |
| 145 | 34 | NSAID | 1.04 (0.74, 1.46) | 1.03 (0.73, 1.46) | |
| 1773 | 370 | None | 1 | 1 | |
| Peri-ovulatory | 148 | 35 | Acetaminophen | 1.05 (0.74, 1.49) | 0.97 (0.68, 1.37) |
| 30 | 7 | Aspirin | 1.18 (0.61, 2.27) | 1.20 (0.62, 2.29) | |
| 151 | 36 | NSAID | 1.08 (0.77, 1.52) | 1.15 (0.82, 1.62) | |
| 1904 | 376 | None | 1 | 1 | |
| Implantation | 180 | 49 | Acetaminophen | 1.25 (0.92, 1.69) | 1.16 (0.85, 1.59) |
| 25 | 9 | Aspirin | 1.97 (1.19, 3.27) | 2.05 (1.23, 3.41) | |
| 146 | 37 | NSAID | 1.09 (0.77, 1.54) | 1.11 (0.79, 1.57) | |
| 2032 | 377 | None | 1 | 1 | |
| Non- Menstrual Days | 405 | 96 | Acetaminophen | 1.17 (0.93, 1.48) | 1.14 (0.90, 1.44) |
| 58 | 14 | Aspirin | 1.14 (0.72, 1.82) | 1.11 (0.70, 1.75) | |
| 341 | 74 | NSAID | 0.93 (0.72, 1.21) | 0.96 (0.74, 1.25) | |
| 1813 | 348 | None | 1 | 1 |
a
Categories are not mutually exclusive and do not sum to the total number of cycles
b
Minimally adjusted model contains all medication variables, age, race and education
c
Adjusted model is the minimal model plus frequency of intercourse in the fertile window, body mass index, caffeine intake, alcohol intake, and a history of migraines or uterine fibroids.