Table 1.
Socio-demographic, reproductive characteristics and medical history of the study participants attended the National Research Center for Mother and Child Health, Astana, Kazakhstan.
| Variable | Total (n = 178) | Controls (n = 78) | RPL Cases (n = 70) | t/χ2 | p-Value |
|---|---|---|---|---|---|
| Age in years, mean ± SD | 34.8 ± 7.1 | 35.7 ± 7.0 | 33.6 ± 7.0 | t = 1.82 | 0.07 |
| BMI in kg/m2, mean ± SD | 24.5 ± 4.1 | 24.6 ± 4.2 | 24.5 ± 4.1 | t = 0.15 | 0.91 |
| BMI categories, n (%) | χ2 = 0.01 | 0.55 | |||
| <25 kg/m2 | 90 (60.8) 3 | 47 (60.3) | 43 (61.4) | ||
| ≥25 kg/m2 | 57 (38.5) | 31 (39.7) | 26 (37.1) | ||
| Ethnicity, others n (%) | 13 (8.8) | 5 (6.4) | 8 (11.4) | χ2 = 0.62 | 0.43 |
| Education, n (%) | χ2 = 9.62 | 0.009 | |||
| Elementary | 31 (20.9) | 24 (30.8) | 7 (10.0) | ||
| Secondary | 21 (14.2) | 11 (14.1) | 10 (14.3) | ||
| University | 94 (63.5) | 43 (55.1) | 51 (72.9) | ||
| Family income, n (%) | χ2 = 1.18 | 0.51 | |||
| Low | 29 (19.6) | 18 (23.1) | 11 (15.7) | ||
| Middle | 108 (73.0) | 55 (70.5) | 53 (75.7) | ||
| High | 10 (6.8) | 5 (6.4) | 5 (7.1) | ||
| Menarche in years, mean ± SD | 13.5 ± 1.2 | 13.6 ± 1.2 | 13.4 ± 1.2 | t = 1.23 | 0.22 |
| Gynecological illnesses, n (%) | 25 (16.9) | 14 (17.9) | 11 (15.7) | χ2 = 0.01 | 0.54 |
| Number of pregnancies, mean ± SD | 3.8 ± 1.8 | 3.3 ± 1.5 | 4.5 ± 1.9 | t = −4.37 | <0.001 |
| Para, mean ± SD | 1.7 ± 1.2 | 2.4 ± 0.9 | 0.9 ± 1.1 | t= 9.14 | <0.001 |
| Medical history | |||||
| Toxoplasma gondii, n (%) | 23 (15.5) | 12 (15.4) | 11 (15.7) | χ2 = 2.37 | 0.20 |
| HCMV, n (%) | 23 (15.5) | 13 (16.7) | 10 (14.3) | χ2 = 2.77 | 0.17 |
| Chlamydia trachomatis, n (%) | 22 (14.9) | 12 (15.4) | 10 (14.3) | χ2 = 3.40 | 0.13 |
| Rubella, n (%) | 25 (16.9) | 12 (15.4) | 13 (18.6) | χ2 = 2.70 | 0.28 |
| Ureaplasma, n (%) | 25 (16.9) | 12 (15.4) | 13 (18.6) | χ2 = 11.98 | 0.003 |
| Previous oral contraceptives, n (%) | 23 (15.5) | 15 (19.2) | 8 (11.4) | χ2 = 1.02 | 0.15 |
| Smoking, n (%) | 6 (4.1) | 3 (3.8) | 3 (4.3) | χ2 = 0.00 | 1.00 |
| Alcohol, n (%) | 5 (3.4) | 4 (5.1) | 1 (1.4) | χ2 = 0.55 | 0.09 |
| History of a chronic disease, n (%) | 12 (8.1) | 5 (6.4) | 7 (10.0) | χ2 = 0.25 | 0.62 |
| Family history of a chronic disease, n (%) | 10 (6.8) | 5 (6.4) | 5 (7.1) | χ2 = 0.00 | 1.00 |
| Hypertension, n (%) | 7 (4.7) | 3 (3.8) | 4 (5.7) | χ2 = 0.02 | 0.88 |
| Thyroid disease, n (%) | 16 (10.8) | 5 (6.4) | 5 (7.1) | χ2 = 0.24 | 0.62 |
Medical history characteristics of the study participants are presented in Table 1. Apart from Ureaplasma infection which was higher in RPL cases than in control women (18.6% vs. 15.3%; p = 0.003), no statistically significant differences were found between RPL cases and control subjects.