Table 1.
Baseline Characteristics of Study Participants by Contraceptive Use at Enrollment
| Variable | NHC (n = 428) n (%) | DMPA (n = 331) n (%) | P valuea | COC (n = 376) n (%) | P valueb |
| Age | |||||
| <26 | 36 (8.4) | 90 (27.2) | P < .001 | 80 (21.3) | P < .001 |
| 26–30 | 137 (32.0) | 108 (32.6) | 156 (41.5) | ||
| 31–33 | 110 (25.7) | 73 (22.1) | 84 (22.3) | ||
| 34–38 | 145 (33.9) | 60 (18.1) | 56 (14.9) | ||
| Study site | |||||
| North (Chiang Mai) | 153 (35.8) | 114 (34.4) | P = .003 | 149 (39.6) | P < .001 |
| Northeast (Khon Kaen) | 140 (32.7) | 75 (22.7) | 45 (11.9) | ||
| South (Songkhla and Hat Yai) | 81 (18.9) | 93 (28.1) | 114 (30.3) | ||
| Central (Bangkok) | 54 (12.6) | 49 (14.8) | 68 (18.1) | ||
| Total no. of live births | |||||
| 0 | 7 (1.6) | 1 (0.3) | P < .001 | 14 (3.7) | P < .001 |
| 1 | 107 (25.0) | 212 (64.1) | 247 (65.7) | ||
| >1 | 314 (73.4) | 118 (35.7) | 115 (30.6) | ||
| Duration of COC use prior to enrollment | |||||
| Never | 92 (21.5) | 93 (28.1) | P = .028 | 0 (0) | P < .001 |
| <4 years | 260 (60.8) | 201 (60.7) | 116 (30.9) | ||
| 4–6 years | 67 (15.7) | 34 (10.3) | 189 (50.3) | ||
| >6 years | 9 (2.1) | 3 (0.9) | 71 (18.9) | ||
| Duration of DMPA use prior to enrollment | |||||
| Never | 150 (35.1) | 0 (0) | P < .001 | 105 (27.9) | P < .001 |
| <4 years | 237 (55.4) | 95 (28.7) | 196 (52.1) | ||
| 4–6 years | 38 (8.9) | 188 (56.8) | 71 (18.9) | ||
| >6 years | 3 (0.7) | 48 (14.5) | 4 (1.1) | ||
| Male condom use L6M | |||||
| No | 340 (79.4) | 287 (86.7) | P = .009 | 323 (85.9) | p = .016 |
| Yes | 88 (20.6) | 44 (13.3) | 53 (14.1) | ||
| Age of sexual debut | |||||
| >20 | 175 (40.9) | 129 (38.9) | P = .401 | 140 (37.2) | P = .286 |
| 17–19 | 198 (46.3) | 148 (44.7) | 174 (46.3) | ||
| <17 | 55 (12.9) | 54 (16.3) | 62 (16.5) | ||
| No. of lifetime partners | |||||
| 1 | 318 (74.3) | 255 (77.0) | P = .215 | 262 (69.7) | P = .116 |
| 2 | 55 (12.9) | 47 (14.2) | 70 (18.6) | ||
| 3 | 25 (5.8) | 17 (5.1) | 16 (4.3) | ||
| ≥4 | 30 (7.0) | 12 (3.6) | 28 (7.5) | ||
| No. of partners L6M | |||||
| 0 | 19 (4.4) | 6 (1.8) | P = .129 | 1 (0.3) | P < .001 |
| 1 | 407 (95.1) | 323 (97.6) | 374 (99.5) | ||
| >1 | 2 (0.5) | 2 (0.6) | 1 (0.3) | ||
| New partner L12M | |||||
| No | 406 (99.3) | 319 (98.2) | P = .174 | 372 (99.2) | P = .915 |
| Yes | 3 (0.7) | 6 (1.9) | 3 (0.8) | ||
| Smoked cigarettes L6M | |||||
| No | 418 (97.7) | 317 (95.8) | P = .139 | 366 (97.3) | P = .769 |
| Yes | 10 (2.3) | 14 (4.2) | 10 (2.7) | ||
| Cytology at enrollment | |||||
| Normal | 394 (92.1) | 296 (89.4) | P = .603 | 345 (91.8) | P = .683 |
| Inflammation | 3 (0.7) | 6 (1.8) | 6 (1.6) | ||
| ASC-US | 15 (3.5) | 15 (4.5) | 15 (3.9) | ||
| LSIL | 13 (3.0) | 11 (3.3) | 8 (2.1) | ||
| HSIL | 3 (0.7) | 3 (0.9) | 2 (0.5) | ||
| Worst cytology at follow-up | |||||
| Normal | 349 (81.5) | 239 (72.2) | P = .016 | 286 (76.1) | P = .107 |
| Inflammation | 7 (1.6) | 9 (2.7) | 12 (3.2) | ||
| ASC-US | 36 (8.4) | 47 (14.2) | 42 (11.2) | ||
| LSIL | 26 (6.1) | 20 (6.0) | 19 (5.1) | ||
| HSIL | 10 (2.3) | 16 (4.8) | 17 (4.5) | ||
| Bacterial vaginosis at enrollment | |||||
| Negative | 397 (92.8) | 322 (97.3) | P = .006 | 363 (96.5) | P = .019 |
| Positive | 31 (7.2) | 9 (2.7) | 13 (3.5) | ||
| Prior STI infectionc | |||||
| No | 368 (85.9) | 280 (84.6) | P = .591 | 317 (84.3) | P = .505 |
| Yes | 60 (14.0) | 51 (15.4) | 59 (15.7) | ||
| Cervical ectopyd | |||||
| No | 319 (74.5) | 220 (79.8) | P = .091 | 212 (65.7) | P = .006 |
| Yes | 109 (25.5) | 67 (20.2) | 129 (34.3) |
Abbreviations: ACS-US, atypical squamous cells of undetermined significance; COC, combined oral contraception; DMPA, depomedroxyprogesterone acetate; L6M, last 6 months; L12M, last 12 months; NHC, nonhormonal contraception.
a
Comparing DMPA users vs NHC users.
b
Comparing COC users vs NHC users.
c
Includes laboratory detection of chlamydia, gonorrhea, or syphilis.
d
Diagnosed at 6-month follow-up.