Variables | All JECS Participants | Participants of adjunct study Non-participants | |||||
---|---|---|---|---|---|---|---|
n | n | n | p | ||||
Mothers with live birth | 8873 | 1823 | 7050 | ||||
Age at delivery (yrs) | 8823 | 30.7 ± 5.1 | 1817 | 31.0 ± 5.3 | 7006 | 30.6 ± 5.0 | 0.0022 |
Marital status at registration (Married, %) | 8798 | 94.7 | 1807 | 94.3 | 6991 | 94.8 | 0.39 |
Maternal education (<13 yrs, %) | 8746 | 52.9 | 1790 | 54.1 | 6956 | 52.3 | 0.27 |
Paternal education (<13 yrs, %) | 8695 | 59.3 | 1778 | 62.9 | 6917 | 59.6 | 0.013 |
Household income (million Japanese Yen) (%) | |||||||
< 2 | 575 | 7.4 | 121 | 7.4 | 454 | 7.4 | 0.15 |
2 to <4 | 3111 | 39.9 | 694 | 42.6 | 2417 | 39.2 | |
4 to <6 | 2290 | 29.4 | 454 | 27.8 | 1836 | 29.8 | |
6 to <8 | 972 | 12.5 | 205 | 12.6 | 767 | 12.5 | |
≥ 8 | 842 | 10.8 | 157 | 9.6 | 685 | 11.1 | |
Living together with parents (Yes, %) | 8835 | 46.7 | 1818 | 43.3 | 7017 | 47.5 | 0.0012 |
Smoking habits (%) | |||||||
Never smoked | 4324 | 49.0 | 842 | 46.4 | 3482 | 49.6 | 0.034 |
Ex-smokers who quit before pregnancy | 2099 | 23.8 | 440 | 24.2 | 1659 | 23.6 | |
Ex-smokers who quit after pregnancy | 1752 | 19.8 | 377 | 20.8 | 1375 | 19.6 | |
Smokers during early pregnancy | 657 | 7.4 | 157 | 8.6 | 500 | 7.1 | |
Passive smoking (Yes, %) | 8850 | 66.4 | 1819 | 69.2 | 7031 | 65.7 | 0.0047 |
Alcohol consumption (Drinkers, %) | 8767 | 2.5 | 1791 | 1.7 | 6976 | 2.7 | 0.013 |
Prepregnancy BMI (kg/m2) | 8872 | 21.8 ± 3.6 | 1823 | 21.9 ± 3.9 | 7049 | 21.7 ± 3.6 | 0.019 |
Body weight gain at delivery (kg) | 8822 | 10.8 ± 4.2 | 1813 | 10.4 ± 4.2 | 7009 | 10.9 ± 4.1 | <0.0001 |
Physical activity (mets · min/week) | 8766 | 480 (0–18400) | 1792 | 480 (0–18400) | 6974 | 480 (0–16400) | 0.81 |
Obstetrical/gynecological disease (%) | |||||||
Diabetes mellitus | 8866 | 0.73 | 1822 | 0.49 | 7044 | 0.80 | 0.16 |
Gestational diabetes mellitus | 8866 | 1.5 | 1822 | 1.1 | 7044 | 1.6 | 0.11 |
Pregnancy-induce hypertension | 8866 | 1.1 | 1822 | 2.4 | 7044 | 0.82 | <0.0001 |
Hyperthyroidism | 8866 | 0.43 | 1822 | 0.27 | 7044 | 0.47 | 0.23 |
Intrauterine growth restriction | 8866 | 1.2 | 1822 | 1.4 | 7044 | 1.2 | 0.37 |
Placenta abruption | 8866 | 0.20 | 1822 | 0.0 | 7044 | 0.26 | 0.035a |
Parity (Primipara, %) | 8783 | 39.4 | 1789 | 37.8 | 6994 | 39.8 | 0.12 |
Infertility treatment (Yes, %) | 8814 | 4.6 | 1812 | 5.9 | 7002 | 4.3 | 0.0059 |
Fish intake (g/day) | 8757 | 29.1 (0.8–919) | 1788 | 1788 28.3 (1.2–612) | 6969 | 29.4 (0.8–919) | 0.11 |
Meat intake (g/day) | 8762 | 54.6 (0.4–1740) | 1789 | 55.5 (0.4–1581) | 6973 | 54.3 (1.5–1740) | 0.21 |
Supplemental use (%) | |||||||
Any kind | 8774 | 38.8 | 1793 | 34.2 | 6981 | 40.0 | <0.0001 |
EPA and/or DHA | 8773 | 2.2 | 1792 | 2.5 | 5981 | 2.1 | 0.30 |
Breakfast skipper (Skipper, %) | 8756 | 13.8 | 1788 | 14.8 | 6968 | 13.5 | 0.14 |
Housewife (Yes, %) | 8742 | 44.0 | 1787 | 50.6 | 6955 | 42.3 | <0.0001 |
Number of live births | |||||||
Singleton births (%) | 8873 | 99.2 | 1823 | 99.2 | 7050 | 99.1 | 0.69 |
Gestational age at birth (day) | 8857 | 274.1 ± 11.8 | 1819 | 273.6 ± 13.5 | 7038 | 274.3 ± 11.3 | 0.025 |
Preterm births (<37) (%) | 8857 | 5.5 | 1819 | 5.4 | 7038 | 5.5 | 0.93 |
Sex (Male, %) | 8865 | 51.0 | 1822 | 51.6 | 7043 | 50.9 | 0.35 |
Type of delivery (Transvaginal, %) | 8847 | 82.2 | 1819 | 81.9 | 7028 | 82.2 | 0.74 |
Birth weight (g, Singleton births) | |||||||
All | 8850 | 3046 ± 441 | 1818 | 3031 ± 479 | 7032 | 3050 ± 431 | 0.12 |
Male | 4481 | 3095 ± 433 | 939 | 3076 ± 485 | 3580 | 3089 ± 433 | 0.43 |
Female | 4289 | 3010 ± 427 | 876 | 2984 ± 468 | 3450 | 3008 ± 424 | 0.15 |
Low birth weight (<2500 g) (%) | 8850 | 8.2 | 1818 | 9.8 | 7032 | 7.8 | 0.005 |