TABLE 3c.

Associations between maternal anaemia and iron status at early and mid-pregnancy with heart rate in late pregnancy (multivariable logistic regression).

Gestational age	Predictor	Heart rate above median (HR > 87.5 bpm)
		Model 1 (n = 189)			Model 2 (n = 184)			Model 3*
		OR	95% CI	p	OR	95% CI	p	OR	95% CI	p
< 18 weeks	Anaemia (Hb < 10.5g/dL)	0.86	0.41, 1.81	0.681	1.02	0.47, 2.25	0.955	NA	-	-
	Anaemia (Hb < 11.0g/dL)	0.65	0.35, 1.22	0.182	0.77	0.40, 1.49	0.437	-	-	-
	ID (Fer < 15μg/L)	0.89	0.39, 2.02	0.784	0.80	0.34, 1.89	0.608	-	-	-
	IDE (sTfR > 8.3mg/L)	1.07	0.49, 2.31	0.869	1.28	0.57, 2.89	0.552	-	-	-
		Model 1 (n = 189)			Model 2 (n = 186)			-
22 weeks	Anaemia (Hb < 10.5g/dL)	1.46	0.78, 2.74	0.233	1.39	0.72, 2.68	0.327	NA	-	-
	Anaemia (Hb < 11.0g/dL)	1.31	0.73, 2.34	0.370	1.37	0.74, 2.53	0.314	-	-	-
	ID (Fer < 15μg/L)	1.03	0.50, 2.13	0.942	1.10	0.52, 2.33	0.795	-	-	-
	IDE (sTfR > 8.3mg/L)	0.85	0.44, 1.67	0.639	0.74	0.37, 1.49	0.398	-	-	-

OR, odds ratio; CI, confidence interval; Hb, haemoglobin; Fer, serum ferritin; sTfR, soluble transferrin receptor; bpm, beats per minute; ID, iron deficiency; IDE, iron deficiency erythropoiesis; HR, heart rate. Associations were assessed with multivariable logistic regression, odds ratios and 95% confidence intervals. Model 1 is adjusted for maternal age and living standards measure (socio-economic status); model 2 is adjusted additionally for gestational age, CRP and maternal BMI at baseline, HIV status throughout pregnancy, and aspirin prescription during mid-pregnancy;

^*, model 3, not performed. p < 0.05 was considered significant and p between 0.05 and 0.08 had a tendency towards significance.