Fetal heart biventricular diameter/foot length index as a diagnostic marker of fetal macrosomia in the second and third trimester of pregnancy

Figures & data

Figure 1. Measurement of fetal heart biventricular diameter (AP) in relation to gestational age in a control group (n = 109) of healthy fetuses with Normal Heart Anatomy, no Extracardiac malformations, no Extracardiac anomalies. Data from the Department of Diagnoses and Prevention of Fetal Malformations, Medical University of Lodz of 2016–2020. Gestational age in weeks.

Figure 2. Measurement of fetal foot length in relation to gestational age in a control group of 109 healthy fetuses (Normal Heart Anatomy, no Extracardiac malformations, no Extracardiac anomalies) with a trend line. Data from the Department of Diagnoses and Prevention of Fetal Malformations, Medical University of Lodz of 2016–2020. Gestational age in weeks.

Figure 3. Measurement of the fetal heart AP to foot index (AP/Foot Index) in relation to gestational age in a control group of 109 healthy fetuses (Normal Heart Anatomy, no Extracardiac malformations, no Extracardiac anomalies) with a trend line. Data from the Department of Diagnoses and Prevention of Fetal Malformations, Medical University of Lodz of 2016–2020. Gestational age in weeks.

Table 1. Fetuses with a birth weight of more than or equal to 4000 g with the AP and foot measurements and the AP/Foot Index calculated and compared with fetal estimated weight based on ultrasound calculations.

Case no.	Fetal age according to LMP	Fetal age according to biometry	Estimated fetal weight based on ultrasound (g)	Fetal heart – AP (mm)	Fetal foot (mm)	AP/Foot Index	Neonatal birth weight (g)
1	33.4	34.5	2639 ± 385	36	74	0.49	4050
2	34.2	35.3	2529 ± 369	42	71	0.59*	4070
3	37.6	39.6	3588 ± 524*	44	68	0.65*	4100
4	38.5	39.5	4026 ± 588*	43,8	81,5	0.54*	4120
5	33.1	35.0	2415 ± 353	37	71	0.52	4130
6	37.6	39.2	3664 ± 535*	44	84	0.52	4130
7	31.0	34.2	2239 ± 327	38	65	0.58*	4150
8	33.6	33.0	2126 ± 310	37	74	0.50	4180
9	37.3	37.2	3079 ± 425	43	76	0.57*	4190
10	35.4	35.0	2802	39	77	0.51	4450
11	35.2	35.4	2724 ± 398	33	60	0.55*	4080
12	37.3	37.2	3079 ± 425	43	76	0.57*	4190
13	29.5	28.4	2590 ± 38	18	30	0.60*	4000
14	38.5	39.5	4026 ± 588*	43,8	81,5	0.54*	4120
15	24.1	23.6	649 ± 95	21	40	0.53*	4010
16	34.4	36.6	1210 ± 177	32,7	51,5	0.63*	4220
17	32.5	36.1	2773	37	78	0.47	4000
18	28.5	27.6	1275 ± 186	31	53	0.58*	4000
19	21.6	22.3	512 ± 75	19	42	0.45	4090
20	27.2	26.5	981 /− 143	28	51	0.55*	4220
Average value				35.52	65.23	0.55	4125
STD				8.40	15.61	0.051	104.76

*Fetuses with the AP/Foot Index > 0.52.

Table 2. Statistical analysis for fetal AP/Foot Index with values exceeding 0.52 compared to LGA fetuses detected based on ultrasound according to fetal biometry.

Factor	Fetal AP/Foot Index ≥ 0.52 (%)	LGA in ultrasound exam based on fetal biometry without AP/Foot Index (%)
Sensitivity	65.00	20.00
Specificity	97.62	94.56
Negative predictive value	97.62	94.56
Positive predictive value	65.00	20.00