. 2018 Feb 1;2018:9203985. doi: 10.1155/2018/9203985

Table 2.

Maternal characteristics from the Danish Fetal Medicine Database; ^∗Wilcoxon–Mann–Whitney test, ^∗∗Student's t-test, ^∗∗∗chi² test; ^∧Caucasian: European, Middle Eastern, North African, Hispanic; ^∧∧Non-Caucasian: Afro Caribbean, Asian, Oriental.

Characteristic	<week 22	≥week 22	p value
Characteristic	N = 187	N = 16	p value
Maternal age, years [95% CI]	29.7 [29.0; 30.4]	29.8 [27.4; 32.1]	0.88^∗
BMI, [95% CI]	25.6 [24.7; 26.5]	28.1 [24.9; 31.3]	0.08^∗∗
Smokers, % [95% CI]	3.8 [1.5; 7.6]	6.2 [0.2; 30.2]	0.62^∗∗∗
Ethnicity, % [95% CI]
(i) Caucasian^∧	93.2 [88.6; 96.3]	86.7 [59.5; 98.3]	0.35^∗∗∗
(ii) Non-Caucasian^∧∧	6.8 [3.7; 11.4]	13.3 [1.7; 40.5]	0.35^∗∗∗
Conception, % [95% CI]
(i) Spontaneous	90.1 [84.8; 94.0]	93.8 [69.8; 99.8]	0.63^∗∗∗
(ii) Fertility treatment	9.9 [6.0; 15.2]	6.3 [0.2; 30.2]	0.63^∗∗∗