Table 2.

Multinomial comparisons for categorical data (N = 1,145)

Socioeconomic variable	Underweight category				Normal weight category			Overweight category				Obese category
	GBMI ( > 10 to < 19.8 kg/m2)				GBMI ( > 19.8 to < 26.1 kg/m2)			GBMI ( > 26.1 < 29 kg/m2)				GBMI ( > 29 to < 50 kg/m2)
	n	%	OR	95% CI	n	%	OR	n	%	OR	95% CI	n	%	OR	95% CI
Smoking			2.226	0.292,16.946			1			0.989	0.426,2.296			1.232	0.591,2.571
No	56	98.2			478	96.2		199	96.1			372	96.9
Yes	1	0.8			19	3.8		8	3.9			12	3.1
Identity document			1.167	0.528,2.581			1			0.681	0.392,1.183			0.762	0.495,1.174
No	8	14			61	12.3		18	8.7			37	9.6
Yes	49	86			436	87.7		189	91.3			347	90.4
Booked antenatal clinic			1.422	0.768,2.634			1			1.254	0.859,1.831			1.084	0.787,1.492
No	16	28.1			107	21.5		53	25.6			88	22.9
Yes	41	71.9			390	78.5		154	74.4			296	77.1
Marital status			1.612	0.928,2.800						0.826	0.594,1.149			0.909	0.695,1.190
Single	32	56.1			220	44.3		82	39.6			161	41.9
Married/cohabiting	25	43.9			227	55.7		125	60.4			223	58.1
Employed			1.391	0.637,3.038			1			0.818	0.548,1.220			0.952	0.677,1.337
No	49	85.9			405	81.5		162	78.3			310	80.7
Yes	8	14.1			92	18.5		45	21.7			74	19.3
Income (SAR)			2.145	1.184,3.885*			1			1.096	0.791,1.517			1.249	0.955,1.634
0–2000 SAR	40	70.2			260	52.3		113	54.6			222	57.8
> 2000 SAR	17	29.8			237	47.7		94	45.4			162	42.2
Housing type			1.392	0.740,2.620			1			0.765	0.545,1.075			1.115	0.833,1.491
Informal	43	75.4			342	68.8		130	65			273	71.1
Formal	14	25.6			155	31.2		70	35			111	28.9
Electricity			1.252	0.539,2.909			1			1.172	0.700,1.965			1.098	0.712,1.694
No	7	12.3			50	10.1		24	11.6			42	10.9
Yes	50	87.7			447	89.9		183	88.4			342	89.1
Previous stillbirths			1.341	0.701,2.565			1			0.885	0.621,1.260			1.125	0.833,1.581
No	44	77.1			356	71.6		143	69.1			284	73.9
Yes	13	22.9			141	28.4		64	30.9			100	26.1
Termination previous pregnancy			0.851	0.289,2.510			1			1.044	0.524,2.081			1.306	0.717,2.380
No	53	92.9			467	93.9		195	94.2			366	95.3
Yes	4	7.1			30	6.1		12	5.8			18	4.7
Previous low birth weight baby			1.189	0.454,3.113			1			1.201	0.683,2.110			1.041	0.669,1.621
No	52	91.2			446	89.7		189	91.3			346	90.1
Yes	5	8.8			51	10.3		18	8.7			38	9.9
Tuburculosis status			287641.1	?			1			0.415	0.026,6.672			0.385	0.035,4.263
Negative	57	100			496	99.7		206	99.7			382	99.4
Positive	0	0			1	0.3		1	0.3			2	0.6
HIV status			1.131	0.590,2.170			1			1.050	0.719,1.532			1.147	0.837,1.571
Negative	44	77.2			368	74.9		157	75.8			295	77.4
Positive	13	22.8			123	25.1		50	24.1			86	22.6
Age Quartiles (years)
< 22	17	29.8	1.262	0.569,2.796	147	29.6	1	64	30.9	1.136	0.725,1.780	101	26.3	0.982	0.673,1.431
22.1–26	11	19.3	1.121	0.467,2.691	107	21.5	1	41	19.8	1.000	0.609,1.640	95	24.7	1.268	0.857,1.878
26.1–30	18	31.6	1.596	0.724,3.522	123	24.7	1	56	27.1	1.188	0.747,1.889	104	27.1	1.208	0.824,1.770
> 30	11	19.3	1		120	24.1	1	46	22.2	1		84	21.9	1
Height Quartiles (meters)
< 1.54	13	22.8	1.027	0.452,2.334	134	27.0	1	47	22.7	0.636	0.409,0.990	111	28.9	1.182	0.817,1.711
1.541–1.59	11	19.3	1.200	0.508,2.836	97	19.5	1	35	16.9	0.655	0.403,1.062	82	21.4	1.206	0.809,1.799
1.591–1.63	21	36.8	1.599	0.756,3.381	139	28.0	1	55	26.6	0.718	0.468,1.101	102	26.6	1.047	0.722,1.520
> 1.631	12	21.1	1		127	25.6	1	70	33.8	1		89	23.2	1
Parity
0	22	38.6	0.645	0.174,2.390	182	36.6	1	90	43.5	1.978	0.643,6.089	149	38.8	2.620	0.938,7.318
1–2	28	49.1	0.545	0.150,1.986	274	55.1	1	102	49.3	1.489	0.486,4.559	208	54.2	2.429	0.876,6.738
3	4	7.0	0.853	0.168,4.326	25	5.0	1	11	5.3	1.760	0.477,6.491	22	5.7	2.816	0.886,8.948
> 4	3	5.3	1		16	3.2	1	4	1.9	1		5	1.3	1
Education
Primary	3	5.3	1.500	0.146,15.461	36	7.2	1	14	6.8	0.778	0.283,2.137	37	9.6	1.542	0.651,3.653
Secondary	53	93.0	2.153	0.282,16.458	443	89.1	1	184	88.9	0.831	0.366,1.883	335	87.2	1.134	0.539,2.387
Tertiary	1	1.8	1		18	3.6	1	9	4.3	1		12	3.1	1

GBMI gestational body mass index, n number, OR odds ratio, CI confidence interval, SAR South African Rands, HIV human immunodeficiency virus,

^*P < 0.05