Intention-to-treat analysis of continued use of the intrauterine device (IUD) among women randomised to immediate or delayed insertion of the copper IUD after medical abortion at 17–20 weeks’ gestation
| Immediate group (n=55) | Delayed group (n=57) | Pearson’s Chi-square test | |
| n (%) | n (%) | P value* | |
| IUD inserted as planned | 45 (81.8) | 12 (21.1) | <0.001 |
| At 6 weeks | |||
| Using original IUD†‡ | 31 (56.4) | 11 (19.3) | <0.001 |
| IUD removed or expulsed | 14 (25.5) | 1 (1.8) | |
| IUD never placed | 8 (14.5) | 45 (78.9) | |
| Lost to follow-up | 2 (3.6) | 0 (0.0) | |
| Using any IUD | 42 (76.4) | 23 (40.4) | <0.001 |
| At 3 months | |||
| Using original IUD | 27 (49.1) | 10 (17.5) | <0.001 |
| IUD removed or expulsed | 14 (25.5) | 1 (1.8) | |
| IUD never placed | 8 (14.5) | 45 (78.9) | |
| Lost to follow-up | 6 (14.5) | 1 (1.8) | |
| Using any IUD | 38 (69.1) | 21 (36.8) | <0.001 |
| At 6 months | |||
| Using original IUD | 22 (40.0) | 8 (14.0) | 0.002 |
| IUD removed or expulsed | 15 (27.3) | 2 (3.5) | |
| IUD never placed | 8 (14.5) | 45 (78.9) | |
| Lost to follow-up | 10 (18.2) | 2 (3.5) | |
| Using any IUD | 30 (54.6) | 15 (26.3) | 0.003 |
*P values refer to comparison of non-missing data.
†At interim analysis (n=64), conducted and analysed by the research team, 15/31 (48%) in the immediate and 7/33 (21%) in the delayed group were using the original IUD at 6 weeks (p=0.02).
‡Defined as use of an IUD adequately placed with no clinical indication for removal. Includes two participants for whom asymptomatic use was self-reported.
IUD, intrauterine device.