Table 1 Characteristics of the sample (mean ± SD or n (%))
Interpregnancy interval, months | P value | ||
|---|---|---|---|
< 12 (n = 717) | ≥ 12 (n = 4411) | ||
Sociodemographic characteristics | |||
Maternal age, years | 29.27 ± 4.1 | 31.10 ± 3.9 | < 0.001 |
Maternal education < 12 years | 332 (46.3%) | 2037 (46.2%) | 0.971 |
Income < 4000 RMB/month | 543 (75.7%) | 3029 (68.7%) | < 0.001 |
Perinatal health status and lifestyle | |||
Parity ≥ 3 | 376 (52.4%) | 1939(44.0%) | < 0.001 |
Prepregnancy overweight/obesity | 170 (23.7%) | 959(21.7%) | 0.238 |
SBP, mmHg | 110.90 ± 10.2 | 110.19 ± 10.0 | 0.081 |
DBP, mmHg | 69.58 ± 7.6 | 68.86 ± 7.5 | 0.017 |
Depression during pregnancy | 118 (16.5%) | 575 (13.0%) | 0.015 |
Gestational diabetes mellitus | 130 (18.1%) | 907 (20.6%) | 0.124 |
Anemia during pregnancy | 252 (35.1%) | 1703 (38.6%) | 0.117 |
FPG, mmol/L | 4.54 (4.27–4.84) | 4.54 (4.28–4.86) | 0.796 |
Insulin, IU/L | 8.15 (6.10–10.98) | 7.80 (5.7–10.4) | 0.051 |
Vitamin D supplement | 358(49.9%) | 2384 (54.0%) | 0.172 |
Folic acid supplement | 309(43.1%) | 1843 (41.8%) | 0.567 |
Physical activity < 3 days/week | 388(54.1%) | 2478 (56.2%) | 0.248 |
Birth outcomes | |||
Cesarean section | 239(33.3%) | 1667 (37.8%) | 0.042 |
Male | 397(55.4%) | 2337 (53.0%) | 0.500 |
Gestational week at birth, week | 39.03 ± 1.2 | 38.87 ± 1.4 | 0.005 |
Birth weight, g | 3458 ± 450 | 3431 ± 450 | 0.179 |
Postnatal factors | |||
Postpartum depression | 264 (36.8%) | 1164 (26.4%) | 0.008 |
Exclusive breastfeeding > 6 months | 574 (80.1%) | 3564 (80.8%) | 0.849 |
Feeding difficulties | 154 (21.5%) | 782 (17.7%) | 0.260 |
Poor sleeping in infants | 158 (22.0%) | 930 (21.1%) | 0.768 |
Fever in infants ≥ 38.5 °C | 384 (53.6%) | 2311 (52.4%) | 0.890 |
Parents as primary caregivers | 472 (65.8%) | 3013 (68.3%) | 0.535 |
Number of siblings ≥ 2 | 286 (39.9%) | 1653 (37.5%) | 0.762 |
ASQ-3 at 12 monthsa | |||
Scores for communication domain | 52.6 ± 10.1 | 54.3 ± 8.2 | 0.032 |
Failure to communication domain | 32 (8.8%) | 104 (4.6%) | 0.001 |
Scores for gross motor domain | 46.4 ± 13.9 | 46.1 ± 13.7 | 0.807 |
Failure to gross motor domain | 17(4.7%) | 102(4.6%) | 0.908 |
Scores for fine motor domain | 51.7 ± 11.3 | 53.1 ± 9.6 | 0.058 |
Failure to fine motor domain | 29 (8.0%) | 106 (4.7%) | 0.009 |
Scores for problem-solving domain | 50.8 ± 10.6 | 50.9 ± 10.4 | 0.922 |
Failure to problem-solving domain | 12(3.3%) | 67(3.0%) | 0.742 |
Scores for personal social domain | 47.6 ± 12.4 | 49.3 ± 11.5 | 0.010 |
Failure to personal social domain | 36 (9.9%) | 138 (6.2%) | 0.008 |