Table 2.

Log binomial regression analyses examining the association between second trimester maternal serum biomarkers and severe preeclampsia.

	No Preeclampsia or Eclampsiaa	Severe preeclampsia
	n (%)	Early onsetb	Late onsetc
		n (%) RR (95% CI)	n (%) RR (95% CI
No abnormal biomarkersd (n = 93,228)	92,562 (99.3) Referent	133 (0.1)	533 (0.6)
“High” Biomarker (MoM ≥ 95th)
AFP (n = 6,833)	6,687 (97.9)	74 (1.1) 7.1 (4.3, 11.7)e	72 (1.1) 2.5 (1.5, 4.3)e
hCG (n = 6,863)	6,709 (97.8)	68 (1.0) 6.9 (4.3, 11.0)e	86 (1.3) 3.5 (2.3, 5.4)e
uE3 (n = 7,179)	7,112 (99.1)	13 (0.2) 1.3 (0.5, 3.2)	54 (0.8) 1.0 (0.5, 2.1)
INH (n = 6,719)	6,494 (96.7)	106 (1.6) 11.4 (7.5, 17.4)e	119 (1.8) 3.5 (2.2, 5.5)e
“Low” Biomarker (MoM ≤ 5th)
AFP (n = 6,789)	6,739 (99.3)	9 (0.1) 0.6 (0.2, 2.6)	41 (0.6) 0.5 (0.2, 1.6)
hCG (n = 6,321)	6,273 (99.2)	11 (0.2) 0.3 (0.0, 2.5)	37 (0.6) 0.8 (0.3, 2.0)
uE3 (n = 5,450)	5,360 (98.4)	34 (0.6) 3.8 (2.0, 7.3)e	56 (1.0) 2.8 (1.6, 4.9)e
INH (n = 7,155)	7,111 (99.4)	8 (0.1) 0.7 (0.2, 2.3)	36 (0.5) 0.6 (0.4, 1.6)

RR, Relative Risk; 95% CI, Confidence Interval; AFP, alpha-fetoprotein; MoM, Multiple of the Median; hCG, human choronic gonatotropin; uE3, unconjugated estriol; INH, inhibin-A

^aNo mild or severe preeclampsia or eclampsia.

^bBinomial analyses included black race/ethnicity and any diabetes (all dichotomized as yes versus no).

^cBinomial analyses included Hispanic and black race/ethnicity, maternal age ≤ 17 years, maternal age ≥ 35 years, weight at testing > 95^th percentile and any diabetes (all dichotomized as yes versus no).

^dAFP, hCG, uE3 and INH MoMs all between the 5^th and 95^th percentile (AFP > 0.60, < 1.74; hCG > 0.42, < 2.35; uE3 >0.61, < 1.49; INH > 0.48, < 1.95)

^ep < 0.001