Table 2.
Descriptive data of the mother/child pairs grouped according to the degree of placental DNA methylation
| Maternal characteristics | Degree of placental DNA methylation | ||
|---|---|---|---|
| Quintiles 1–4 | Quintile 5 | p valuea | |
| (n = 824) | (n = 206) | ||
| Maternal age, years | 29.9 ± 6.0 | 30.3 ± 5.5 | 0.407 |
| Ethnicity (Caucasian, non-Caucasian), % | 94.3/5.7 | 90.3/9.7 | 0.037 |
| Maternal height, cm | 167.0 ± 6.9 | 166.5 ± 7.3 | 0.365 |
| Body mass index before pregnancy, kg/m2 | 23.2 ± 4.5 | 22.8 ± 4.4 | 0.094 |
| Body mass index 3rd trimester, kg/m2 | 27.6 ± 4.5 | 27.4 ± 4.3 | 0.801 |
| Hypertension before/during pregnancy, % | 2.0/3.5 | 3.4/4.9 | 0.200/0.443 |
| Diabetes mellitus during pregnancy, % | 4.1 | 10.7 | 0.0002 |
| Diabetes in family, % | 38.1 | 38.2 | 0.964 |
| Mean systolic blood pressure 3rd trimester, mmHg | 116.4 ± 11.0 | 115.3 ± 11.5 | 0.202 |
| Mean diastolic blood pressure 3rd trimester, mmHg | 70.4 ± 7.5 | 70.0 ± 7.5 | 0.491 |
| Smoking before/during pregnancy, % | 35.4/13.3 | 34.6/14.7 | 0.828/0.635 |
| Placental DNA methylation, % | 2.84 ± 0.32 | 3.71 ± 0.34 | <0.0001 |
| Parity number <2/≥2, % | 76.1/23.9 | 73.8/26.2 | 0.481 |
| s/p 2 or more miscarriages, % | 6.3 | 7.3 | 0.613 |
| twin gestations, % | 1.8 | 3.4 | 0.161 |
| Gestational age at delivery, weeks | 38.7 ± 2.1 | 38.8 ± 1.8 | 0.989 |
| Preterm birth (<37 weeks), % | 10.3 | 10.3 | 0.983 |
| Birth weight, g | 3334.8 ± 628.3 | 3358.5 ± 661.4 | 0.634 |
| AGA/SGA/LGA, % | 78.8/13.0/8.2 | 73.0/12.7/14.2 | 0.028 |
| Birth lenght, cm | 50.6 ± 3.1 | 50.5 ± 3.6 | 0.951 |
| Child head circumference, cm | 34.7 ± 1.7 | 34.6 ± 1.7 | 0.436 |
| Ponderal index, kg/m3 | 25.5 ± 2.5 | 25.5 ± 2.7 | 0.943 |
| Mode of delivery (spontaneous, OVD, c-section; %) | 66.2/8.1/25.8 | 70.1/5.2/24.7 | 0.387 |
| Child sex, male/female, % | 52.3/47.7 | 49.8/50.2 | 0.522 |
| Apgar score at 5 min | 9.3 ± 1.0 | 9.2 ± 1.1 | 0.084 |
| Apgar score at 10 min | 9.6 ± 0.7 | 9.5 ± 0.8 | 0.011 |
| Maternal HbA1c, m | 43 ± 7.7 | 45 ± 8.7 | 0.257 |
Data are given as mean ± SD or percentage
aComparison between “Quintiles 1–4” and “Quintile 5”