Newborn phosphocalcic metabolism after intravenous iron administration during pregnancy

Figures & data

Table 1. Descriptive statistics of mothers and newborns per type of iron treatment.

Variables	Oral	Intravenous	p-value
Maternal age, y (median)	35 (31–37)	32 (29–35)	.144
Maternal BMI (kg/m^2)	21.8 (20.3–24.6)	23.8 (20.9–27.2)	.552
Parity			.632
Nulliparous	8 (38.1%)	11 (50.0%)
Multiparous (≥1)	13 (61.9%)	11 (50.0%)
Maternal hemoglobin (g/L)	128 (118–133)	122 (113.5–127)	.106
Maternal ferritin (ug/L)	44 (23–49)	77 (33–231)	.029
Maternal calcemia (mmol/L)	2.28 (2.2–2.3)	2.26 (2.2–2.3)	.512
Maternal phosphatemia (mmol/L)	1 (0.9–1.1)	1.04 (0.9–1.1)	.679
Maternal HP (<0,8mmol/L)	1 (4.8%)	3 (13.6%)	.607¹
Delivery route			.430
Vaginal	14 (66.7%)	18 (81.8%)
Cesarean section	7 (33.3%)	4 (18.2%)
Birth weight (g)	3550 (3205 − 3750)	3435 (3132.5–3751.2)	.981
Cord calcemia (mmol/L)	2.67 (2.5–2.8)	2.64 (2.6–2.8)	.990
Cord phosphatemia (mmol/L)	1.7 (1.6–1.8)	1.71 (1.6–2)	.697
Fetal HP (<1.3 mmol/L)	0	1 (4.5%)	.999¹

Continuous variables are described using median and quartiles (Q1–Q3), and categorical variables are expressed as n and percentages (%).

¹Fisher’s exact test.

BMI, body mass index; HP, hypophosphatemia.

Table 2. Multiple linear regression predicting cord phosphate by iron administration route.

Variable	Simple: coefficient [95%CI]	Simple: p-value	Multiple: coefficient [95%CI]	Multiple: p-value
(Intercept)			0.00 [−4.73 to 4.73]	.999
Iron administration route
Oral	(Reference)		(Reference)
Intravenous	0.02 [−0.23 to 0.28]	.857	0.01 [−0.21 to 0.23]	.919
Gestational age	−0.03 [−0.15 to 0.09]	.617	0.04 [−0.08 to 0.16]	.535
Maternal BMI	0.03 [0.01 to 0.06]	.005	0.04 [0.01 to 0.07]	.004
Neonate birth weight	−0.06 [−0.30 to 0.19]	.644	−0.18 [−0.43 to 0.06]	.131

BMI, body mass index.

Table 3. Multiple linear regression predicting cord calcium by iron administration route.

Variable	Simple: coefficient [95%CI]	Simple: p-value	Multiple: coefficient [95%CI]	Multiple: p-value
(Intercept)			2.01 [−0.61 to 4.64]	.121
Iron administration route
Oral	(reference)		(reference)
Intraveinous	0.00 [−0.11 to 0.10]	.933	−0.01 [−0.12 to 0.10]	.891
Gestational age	0.00 [−0.05 to 0.06]	.874	0.01 [−0.06 to 0.08]	.768
Maternal BMI	0.01 [0.00 to 0.02]	.054	0.01 [0.00 to 0.02]	.108
Neonate birth weight	0.04 [−0.08 to 0.17]	.473	0.02 [−0.15 to 0.18]	.824

BMI, body mass index.

Figure 1. Scatterplot between cord blood phosphatemia and maternal phosphatemia.

Data availability statement

The data that support the findings of this study are available from the corresponding author, F.S., upon reasonable request.