J Clin Gynecol Obstet

Journal of Clinical Gynecology and Obstetrics, ISSN 1927-1271 print, 1927-128X online, Open Access

Article copyright, the authors; Journal compilation copyright, J Clin Gynecol Obstet and Elmer Press Inc

Journal website http://www.jcgo.org

Original Article

Volume 3, Number 1, February 2014, pages 22-29

Improved Early Prediction of Preterm Pre-Eclampsia by Combining Second Trimester Maternal Serum Alpha-Fetoprotein and Uterine Artery Doppler

**Table 1.** Demographic Characteristics of Study Population
Characteristic	Number n (%) n = 724
Race
Caucasian	383 (52.9)
Afro-Caribbean	289 (39.9)
Asian	43 (5.9)
Oriental	7 (0.9)
Nulliparous	354 (48.8)
Smoker	166 (22.9)
Previous severe pre-eclampsia	21 (2.9)
Previous babies < 2,500g after 37 weeks	11 (1.5)
Previous premature delivery	12 (1.6)

Table 1. Demographic Characteristics of Study Population

Characteristic

Number n (%)
n = 724

Race

Caucasian

383 (52.9)

Afro-Caribbean

289 (39.9)

Asian

43 (5.9)

Oriental

7 (0.9)

Nulliparous

354 (48.8)

Smoker

166 (22.9)

Previous severe pre-eclampsia

21 (2.9)

Previous babies < 2,500g after 37 weeks

11 (1.5)

Previous premature delivery

12 (1.6)

**Table 2.** Prediction of Pre-Eclampsia and Preterm Pre-Eclampsia Using Uterine Artery Doppler and MSAFP Alone and in Combination
	Method	Sens(%) (True +ve/Total +ve)	Spec (%) (True -ve/True -ve +False +ve)	PPV (%)	OR (CI)	LR
PE: pre-eclampsia; pret PE: pre-eclampsia requiring delivery before 37 weeks gestation; Sens: sensitivity; Spec: specificity; PPV: positive predictive value; OR: odds ratio; CI: confidence intervals; LR: positive likelihood ratio. MSAFP ≥ 2.0 MoM; * Bilateral notches/mean RI ≥ 0.67; † Bilateral notches/mean RI ≥ 0.55 and unilateral notches/mean RI ≥ 0.65 and MSAFP > 1.2 MoM; ‡ Bilateral notches/mean RI ≥ 0.75 and unilateral notches/mean RI ≥ 0.65; # MSAFP ≥ 2.6 MoM; Φ Bilateral notches/mean RI ≥ 0.55 and unilateral notches/mean RI ≥ 0.65 combined with MSAFP ≥ 1.6 MoM.
PE	MSAFP*	24.4 (10/41)	94.1 (643/683)	20.0	5.185 (2.4 - 11.3)	4.1
Doppler**	60.9 (25/41)	92.9 (635/683)	38.5		8.6
Doppler and MSAFP†	48.8 (20/41)	93.9 (641/683)	32.3	14.5 (7.3 - 28.9)	8
Pret PE	MSAFP#	5.9 (1/17)	96.9 (685/707)	4.3	9.1 (0.2 - 15.3)	1.9
Doppler‡	29.4 (5/17)	97.0 (686/707)	19.2		9.8	< 0.02
Doppler and MSAFPφ	64.7 (11/17)	96.6 (683/707)	31.4	52.2 (17.1 - 152.8)	19.0

Table 2. Prediction of Pre-Eclampsia and Preterm Pre-Eclampsia Using Uterine Artery Doppler and MSAFP Alone and in Combination

Method

Sens(%) (True +ve/Total +ve)

Spec (%) (True -ve/True -ve +False +ve)

PPV (%)

OR (CI)

P value⁺

PE: pre-eclampsia; pret PE: pre-eclampsia requiring delivery before 37 weeks gestation; Sens: sensitivity; Spec: specificity; PPV: positive predictive value; OR: odds ratio; CI: confidence intervals; LR: positive likelihood ratio. *MSAFP ≥ 2.0 MoM; ** Bilateral notches/mean RI ≥ 0.67; † Bilateral notches/mean RI ≥ 0.55 and unilateral notches/mean RI ≥ 0.65 and MSAFP > 1.2 MoM; ‡ Bilateral notches/mean RI ≥ 0.75 and unilateral notches/mean RI ≥ 0.65; # MSAFP ≥ 2.6 MoM; Φ Bilateral notches/mean RI ≥ 0.55 and unilateral notches/mean RI ≥ 0.65 combined with MSAFP ≥ 1.6 MoM.

MSAFP*

24.4 (10/41)

94.1 (643/683)

20.0

5.185 (2.4 - 11.3)

4.1

Doppler**

60.9 (25/41)

92.9 (635/683)

38.5

8.6

Doppler and
MSAFP†

48.8 (20/41)

93.9 (641/683)

32.3

14.5 (7.3 - 28.9)

Pret PE

MSAFP#

5.9 (1/17)

96.9 (685/707)

4.3

9.1 (0.2 - 15.3)

1.9

Doppler‡

29.4 (5/17)

97.0 (686/707)

19.2

9.8

< 0.02

Doppler and MSAFPφ

64.7 (11/17)

96.6 (683/707)

31.4

52.2 (17.1 - 152.8)

19.0

**Table 3.** Summary of Related Studies
Study	Sample	Results
Janiaux 1996 [16]	41 women with abnormal UADs at 20 - 24 weeks and measured AFP	PPV 47%
Chung 2000 [17]	179 women with MSAFP > 2.5MOMs and abnormal UADs between 26 - 28 weeks	PPV 14.5 % MSAFP alone
Konchak 1995 [18]	103 women with unexplained increase AFP had UAD measured between 17 - 22 weeks	Elevated uterine artery RI associated with an increased RR of preeclampsia (RR 41.82, 95% CI 5.36 to 326)
Audibert 2005 [7]	2,615 women had MSAFP and UAD measured in the second trimester	Elevated MSAFP with uterine artery notching had a PPV of 21%

Table 3. Summary of Related Studies

Study

Sample

Results

Janiaux 1996 [16]

41 women with abnormal UADs at 20 - 24 weeks and measured AFP

PPV 47%

Chung 2000 [17]

179 women with MSAFP > 2.5MOMs and abnormal UADs between 26 - 28 weeks

PPV 14.5 % MSAFP alone

Konchak 1995 [18]

103 women with unexplained increase AFP had UAD measured between 17 - 22 weeks

Elevated uterine artery RI associated with an increased RR of preeclampsia (RR 41.82, 95% CI 5.36 to 326)

Audibert 2005 [7]

2,615 women had MSAFP and UAD measured in the second trimester

Elevated MSAFP with uterine artery notching had a PPV of 21%