Table 2.

Cumulative numbers and rates per 100 of selected reasons for IUD removal at 1, 3, 5 and 7 years of use by LNG-IUD and TCu380A IUD in Chinese and non-Chinese centres.

Year Reason for discontinuation	Chinese centres						Non-Chinese centres						p-value 1
	LNG-IUD			TCu380A			LNG-IUD			TCu380A
	Events	Rate	SE	Events	Rate	SE	Events	Rate	SE	Events	Rate	SE
Year 1
Pregnancies, all	2	0.20	0.14	9	0.89	0.29	0	0.00	0.00	2	0.27	0.19	0.9921
Expulsions, all	30	0.03	0.01	34	0.03	0.01	23	0.03	0.01	29	0.04	0.01	0.6780
Bleeding problems	104	10.24	0.95	16	1.56	0.39	56	7.39	0.95	38	5.06	0.80	< 0.0001
Amenorrhea	46	4.81	0.69	1	0.10	0.10	26	3.64	0.70	0	0.00	0.00	0.9839
Reduced bleeding	24	2.48	0.50	2	0.20	0.14	14	1.91	0.51	8	1.09	0.38	0.0206
Increased bleeding	34	3.31	0.56	13	1.27	0.35	16	2.02	0.50	30	4.02	0.72	0.0003
Pain	10	1.02	0.32	11	1.08	0.32	25	3.45	0.68	19	2.63	0.60	0.5672
Nondevice-related reasons	3	0.31	0.18	1	0.10	0.10	24	3.28	0.66	21	2.96	0.64	0.3857
Year 3
Pregnancies, all	6	0.72	0.30	20	2.05	0.45	0	0.00	0.00	4	0.66	0.34	0.9876
Expulsions, all	52	0.06	0.01	55	0.05	0.01	30	0.04	0.01	40	0.06	0.01	0.2786
Bleeding problems	253	26.25	1.43	37	3.75	0.61	110	17.42	1.56	59	9.03	1.15	< 0.0001
Amenorrhea	149	16.88	1.27	1	0.10	0.10	63	10.70	1.31	0	0.00	0.00	0.9777
Reduced bleeding	61	7.15	0.89	10	1.04	0.33	28	5.03	0.96	10	1.44	0.46	0.0669
Increased bleeding	43	4.45	0.67	26	2.63	0.51	19	2.62	0.61	49	7.70	1.09	< 0.0001
Pain	20	2.33	0.52	15	1.51	0.39	39	6.19	0.99	43	7.07	1.06	0.2105
Nondevice-related reasons	11	1.39	0.42	6	0.63	0.26	86	15.49	1.57	71	12.33	1.40	0.2735
Year 5
Pregnancies, all	6	0.72	0.30	23	2.39	0.49	1	0.29	0.29	5	0.98	0.47	0.6700
Expulsions, all	58	0.07	0.01	69	0.07	0.01	34	0.06	0.01	46	0.08	0.01	0.3458
Bleeding problems	346	37.20	1.60	61	6.51	0.81	133	23.73	1.92	82	15.48	1.69	< 0.0001
Amenorrhea	217	26.07	1.54	1	0.10	0.10	76	14.48	1.62	0	0.00	0.00	0.9765
Reduced bleeding	84	10.80	1.14	19	2.09	0.48	34	7.13	1.27	14	2.73	0.78	0.0479
Increased bleeding	45	4.76	0.70	41	4.42	0.68	23	3.98	0.91	68	13.11	1.59	< 0.0001
Pain	26	3.35	0.66	20	2.08	0.46	45	8.10	1.24	55	10.63	1.44	0.0746
Nondevice-related reasons	20	2.98	0.67	15	1.72	0.44	148	32.07	2.28	126	26.29	2.10	0.2896
Year 7
Pregnancies, all	6	0.72	0.30	27	3.01	0.58	1	0.29	0.29	6	1.44	0.65	0.6232
Expulsions, all	69	0.09	0.01	80	0.09	0.01	35	0.06	0.01	49	0.09	0.01	0.1934
Bleeding problems	396	44.41	1.72	87	10.17	1.05	144	28.34	2.27	94	21.60	2.33	< 0.0001
Amenorrhea	245	31.02	1.70	5	0.70	0.31	78	15.56	1.78	0	0.00	0.00	0.9723
Reduced bleeding	98	13.74	1.35	27	3.28	0.63	41	10.56	1.78	17	4.64	1.34	0.0753
Increased bleeding	53	6.57	0.94	55	6.47	0.86	25	5.12	1.21	76	17.31	2.11	< 0.0001
Pain	28	3.78	0.73	29	3.48	0.65	48	9.98	1.64	67	15.80	2.00	0.1179
Nondevice-related reasons	27	4.58	0.89	23	2.94	0.61	195	49.07	2.81	161	38.82	2.62	0.4171

¹p-value for interaction between Chinese and non-Chinese centres by IUD type.