Anxiety and depression are risk factors for recurrent pregnancy loss: a nested case–control study

Table 1 Basic characteristics of the study population in different demographic categories

Characteristics	RPL group (n = 1132)		Control group (n = 1426)		P value^*
Characteristics	n	(%)	n	(%)	P value^*
Age (year)					0.19
≤ 25	38	3.4	59	4.1
26–29	324	28.6	422	29.6
30–34	358	31.6	481	33.7
≥ 35	412	36.4	464	32.5
Ethnicity (%)					0.20
The Han nationality	1045	92.7	1335	93.6
Other	87	7.7	91	6.4
Education					0.09
≤ primary school	59	5.2	64	4.5
Middle school	418	36.9	473	33.2
High or technical school	618	54.6	827	58.0
≥ College graduate	37	3.3	62	4.3
Occupation					0.57
Employed	901	79.6	1148	80.5
Housewife	231	20.4	278	19.5
Monthly income (RMB, Yuan)					0.13
< 2000	333	29.4	360	25.2
2000–3999	468	41.3	620	43.5
4000–5999	104	9.2	139	9.7
≥ 6000	227	20.1	307	21.5
Time limit of past pregnancy loss					0.76
≤ 12 weeks of gestation	1041	92.0	1316	92.3
> 12 weeks of gestation	91	8.0	110	7.7
Embryonic chromosome abnormalities					0.002
No	1109	98.0	1417	99.4
Yes	23	2.0	9	0.6
Previous liveborn					0.001
No	877	77.5	1250	87.7
Yes	255	22.5	176	12.3
Alcohol consumption					0.87
No	1103	97.4	1388	97.3
Yes	29	2.6	27	2.7
Active smoking					0.001
No	1087	96.0	1400	98.2
Yes	45	4.0	26	1.8
Passive smoking					0.11
No	979	86.5	1263	88.6
Yes	153	13.5	163	11.4

ISSN: 1477-7525