TABLE 2.
Factors associated with vaginal douching and loss to follow-up, Longitudinal Study of Vaginal Flora (n = 3,620), Birmingham, Alabama, 1999–2003
| Model A: douching at study entry* | Model B: douching at follow-up visits† | Model C: censoring‡ | ||||
| aOR§ | 95% CI§ | aOR | 95% CI | aOR | 95% CI | |
| Demographic factors | ||||||
| Age (years) | ||||||
| 15–25 | Referent | |||||
| 26–35 | 1.37 | 1.15, 1.64 | 1.24 | 1.08, 1.43 | 1.58 | 1.38, 1.82 |
| 36–46 | 1.57 | 1.21, 2.04 | 1.21 | 1.00, 1.46 | 2.12 | 1.72, 2.61 |
| Race/ethnicity | ||||||
| Non-Black | Referent | |||||
| Black | 1.76 | 1.46, 2.13 | 1.36 | 1.15, 1.62 | 1.49 | 1.29, 1.72 |
| Education completed (years) | ||||||
| ≤12 | Referent | |||||
| >12 | 0.72 | 0.61, 0.86 | 0.69 | 0.60, 0.80 | 1.10 | 0.96, 1.26 |
| Time-dependent factors | ||||||
| Vaginal douching | 30.67 | 26.12, 36.01 | 0.89 | 0.80, 1.00 | ||
| Alcohol drinking | ||||||
| Never | Referent | |||||
| Monthly or less | 1.17 | 0.98, 1.38 | 1.21 | 1.04, 1.41 | 1.23 | 1.08, 1.40 |
| Several times per month or more | 1.59 | 1.33, 1.90 | 1.19 | 1.03, 1.38 | 1.21 | 1.06, 1.38 |
| Cigarette smoking | 1.67 | 1.41, 1.97 | 1.16 | 1.00, 1.33 | 0.79 | 0.70, 0.89 |
| Use of oral contraceptives | 0.96 | 0.81, 1.16 | 1.04 | 0.89, 1.22 | 1.15 | 1.00, 1.33 |
| Tubal ligation | 1.46 | 1.16, 1.82 | 1.42 | 1.19, 1.69 | 1.45 | 1.21, 1.75 |
| Use of depo-medroxyprogesterone acetate | 1.13 | 0.91, 1.40 | 0.89 | 0.74, 1.08 | 1.40 | 1.21, 1.62 |
| Regularity of menstrual cycle | ||||||
| Regular, could predict within 1 week | Referent | |||||
| Not regular, hard to predict | 0.97 | 0.81, 1.16 | 1.05 | 0.88, 1.25 | ||
| Absent | 0.55 | 0.42, 0.71 | 1.28 | 1.04, 1.58 | ||
| Days since last menstrual period | ||||||
| 0–10 | Referent | |||||
| 11–20 | 1.00 | 0.83, 1.20 | 1.02 | 0.89, 1.18 | 0.95 | 0.83, 1.10 |
| 21–30 | 1.21 | 0.99, 1.48 | 0.97 | 0.82, 1.14 | 0.95 | 0.82, 1.11 |
| 31–40 | 1.18 | 0.83, 1.67 | 1.03 | 0.75, 1.41 | 0.77 | 0.61, 0.97 |
| ≥41 | 1.04 | 0.76, 1.42 | 0.62 | 0.48, 0.79 | 0.60 | 0.50, 0.73 |
| No. of recent¶ sexual partners | ||||||
| 0 | Referent | |||||
| 1 | 1.62 | 1.29, 2.03 | 0.87 | 0.74, 1.03 | 0.91 | 0.78, 1.07 |
| ≥2 | 1.75 | 1.31, 2.35 | 0.83 | 0.63, 1.08 | 1.01 | 0.80, 1.29 |
| Consistency of condom use | ||||||
| Never | Referent | |||||
| Sometimes | 1.18 | 0.99, 1.42 | 1.03 | 0.87, 1.23 | 1.19 | 1.02, 1.39 |
| Always | 1.04 | 0.86, 1.26 | 1.02 | 0.86, 1.21 | 1.08 | 0.93, 1.25 |
| Rectal sex | 1.14 | 0.82, 1.58 | 0.99 | 0.72, 1.37 | 1.42 | 1.04, 1.93 |
| Use of insertive sex toy | 1.18 | 0.87, 1.60 | 1.23 | 0.91, 1.65 | 1.01 | 0.75, 1.34 |
| Self-reported vaginal symptoms | ||||||
| Malodor | 0.81 | 0.68, 0.97 | 1.19 | 1.03, 1.39 | ||
| Discharge | 0.95 | 0.82, 1.10 | 0.85 | 0.75, 0.96 | ||
| Irritation | 0.76 | 0.59, 0.96 | 1.06 | 0.86, 1.31 | ||
| Itching | 1.00 | 0.78, 1.27 | 0.91 | 0.75, 1.11 | ||
| Use of over-the-counter antifungal medication or terazol | 0.83 | 0.64, 1.07 | 1.04 | 0.82, 1.32 | ||
| Metronidazole or clindamycin | 1.11 | 0.92, 1.34 | 0.96 | 0.82, 1.12 | ||
| Vaginal Gram stain score | ||||||
| 0–3 (normal flora) | Referent | |||||
| 4–6 (intermediate flora) | 1.14 | 0.97, 1.33 | 0.95 | 0.82, 1.10 | ||
| 7–10 (bacterial vaginosis flora) | 1.21 | 1.05, 1.40 | 0.90 | 0.80, 1.03 | ||
| Sexually transmitted infection | ||||||
| Gonorrhea | 0.78 | 0.57, 1.07 | ||||
| Chlamydia | 1.10 | 0.93, 1.32 | ||||
| Trichomonas | 0.96 | 0.76, 1.21 | 0.70 | 0.59, 0.84 | ||
A logistic regression model for the probability of douching at baseline given factors reported for the 6 months prior to baseline (t = 1).
A pooled logistic regression model for douching at t (t > 1) given factors at t − 1, including douching status, and genital tract infections.
A pooled discrete logistic regression hazard model for attending study visit t (t > 1) given factors reported for the 3 months prior to time t, douching status at t − 1, and genital tract infections measured at time t − 1.
aOR, adjusted odds ratio; CI, confidence interval.
Number of sex partners in the most recent study interval.