Table 2. Macroscopic features in placentas from uncomplicated pregnancies and those complicated by RFM.

	Normal	RFM Total	RFM Normal Outcome	RFM Poor Outcome	Normal vs. RFM Total	Normal vs. RFM Poor Outcome	Normal vs. RFM Normal Outcome
Untrimmed placental weight (g)Δ	657.9±20.1	587.6±26.9	634.2±28.4	503.1±48.4	p = 0.03*	p = 0.0009**	p = 0.42
Trimmed placental weight (g)Δ	544.9±17.3	469.2±22.7	513.2±24.0	383.8±36.4	p = 0.01**	p<0.0001***	p = 0.27
Placental weight centile
<3rd	0	4	1	3	p = 0.065	p = 0.011*	p = 0.281
4th–9th	3	4	1	3
10–49th	19	21	16	5
50–89th	11	6	5	1
90–96th	3	0	0	0
>97th	0	1	1	0
Fetal/Placental Weight Ratio+	5.69 (5.25–6.02)	6.76 (5.69–7.64)	6.73 (5.70–7.70)	6.56 (5.51–7.03)	p<0.0001***	p = 0.07	p = 0.0002***
Placental surface area (cm2)Δ	253.2±8.7	222.3±9.1	236.4±10.2	181.5±12.7	p = 0.01**	p = 0.0004***	p = 0.22
Mean diameter (cm)Δ	17.76±0.31	16.59±0.35	17.12±0.38	15.04±0.54	p = 0.01**	p = 0.0002***	p = 0.19
RoundnessΔ	0.28±0.03	0.29±0.03	0.28±0.03	0.34±0.03	p = 0.70	p = 0.96	p = 0.39
% of maternal surface abnormal pale area+	0.49 (0–1.21)	2.57 (0.39–4.10)	1.24 (0–3.86)	4.07 (2.58–15.5)	p = 0.003**	p<0.0001***	p = 0.05*
Cord insertion†
Central	18 (50%)	10 (28%)	7 (29%)	3 (25%)	p<0.0001***	p = 0.0008***	p = 0.0008***
Eccentric	14 (38%)	14 (38%)	10 (42%)	4 (33%)
Marginal	3 (6%)	12 (28%)	6 (25%)	4 (33%)
Velamentous	2 (6%)	2 (6%)	1 (4%)	1 (9%)

^Δ = Unpaired t test (Data shown are Mean ± SEM),

⁺ = Mann Whitney U Test (Data shown are Median (IQR)),

^† = Fishers' Exact Test. Poor outcome = SGA (individualised birthweight centile ≤10), preterm birth ≤37 weeks, admission to NICU.