Table 2.

Categorized descriptive data for the study population regarding body mass index (BMI) and gestational age. Chi2-test was used for the comparison of frequencies.

Parameter	AS5 min < 7		AS5 min ≥ 7		P
	n	(%)	n	(%)
BMI (kg/m2)
<20	21	7.0	1746	9.6
20–24.9	135	44.9	9457	51.9
25–29.9	84	27.9	4778	26.2
30–34.9	46	15.3	1566	8.6
≥35	15	5.0	692	3.8	<0.001*
Total	301	100	18239	100
Gestational age (weeks)
<28	62	16.9	49	0.2
28–31 + 6	27	7.4	122	0.6
32–36 + 6	45	12.3	981	4.8
37–41 + 6	206	56.3	18045	89.1
≥42	26	7.1	1054	5.2	<0.001
Total	366	100	20251	100

^*Sign difference between BMI ≥ 30 and BMI < 30 (P < 0.001).