Table 2.

Relationship of pregnant women’s demographic and obstetrical history characteristics with the PA intensity based on the results of multiple linear regression analysis

Independent variables		Unstandardised coefficients B	Standardised coefficient beta	95% CI for B	P value*	R2
Prepregnancyor early pregnancy BMI (kg/m2)	Underweight	Reference category				0.261
	Normal	8.63	0.16	−0.63 to 23.9	0.269
	Overweight	10.82	0.2	−4.38 to 26.1	0.162
	Obese	25.6	0.36	9.35 to 41.81	0.002
Ethnicity	Fars	16.94	0.12	1.81 to 32.06	0.028
	Lur	−8.24	−0.08	−18.66 to 2.18	0.121
	Lak	2.96	0.02	−13.23 to 19.17	0.719
	Kurdish	Reference category
Level of education	Secondary	−5.24	−0.05	−16.80 to 6.31	0.372
	Diploma	−8.77	−0.15	−15.10 to −2.44	0.007
	University education	Reference category
No of children		5.95	0.15	1.52 to 10.38	0.009
Gestational age (weeks)		0.81	0.26	0.40 to 1.22	<0.001
Participation in childbirth preparation classes	Yes	−11.27	−0.13	−21.28 to −1.25	0.028
	No	Reference category
A habit of exercising before pregnancy	Yes	6.09	0.11	0.46 to 11.73	0.034
	No	Reference category
Income (millions of rials)	Undesirable <20	3.86	0.04	−6.70 to 14.42	0.473
	Fairly favourable: 20–40	−9.22	−0.17	−15.28 to −3.16	0.003
	Optimal: 40–100	Reference category

*Significance level: p<0.05, bold entries are significant results and are related to statistical tests.

BMI, body mass index; PA, physical activity.