Table 3.

Overview of selected studies on carbohydrate antigen 15-3 levels during normal pregnancy.

	Author/year of publication	Study design	Laboratory technique	Number of patients	Cut-off value	Trimester 1	Trimester 2	Trimester 3	Conclusion
1	Touitou 1989 [6]	cross-sectional	IRMA, CIS-Bio International, Gif-Sur-Yvette, France	T1 n = 32; T2 n = 32; T3 n = 36	<25	11.1 ± 4.2 mean ± SD	14.2 ± 5.1	17.0 ± 5.0	None above cut-off value
2	Schlageter 1998 [7]	longitudinal	ELSA-CA 15-3 (CIS-Bio International), Gif-Sur-Yvette, France	n = 12	<30	9.3 ± 4.0 (mean ± SD) 5 to 15 (range)	14.1 ± 4.1 10 to 22.8	16.5 ± 4.1 8.8 to 24.2	None above cut-off value
3	Botsis 1999 [8]	cross-sectional	EIA, Tumor markers CA 153, Abbott AXSYM system, Abbott Park, Il, USA	T1 n = 20; T2 n = 29; T3 n = 26	<33	18.0 (median) 14 to 30 (range)	20 1.0 to 34	22 12 to 41	5%, 10% and 20% above cut-off value, in the 3 trimesters respectively
4	Cheli 1999 [9]	cross-sectional	Bayer Immuno 1 CA 15-3 assay, Tarrytown, New York, USA)	T1 n = 32; T2 n = 5; T3 n = 53	<35	16.76 (mean)	-	20.78	3.3% above cut-off value
5	Bon 2001 [10]	cross-sectional	Enzymun-Test CA 15-3 (Boehringer, Mannheim, Germany)	T1 n = 127; T2 n = 192; T3 n = 47	Not stated	14.0 (median) 5.0 to 32 (range)	15.0 6.0 to 40	26.0 9 to 56	Raised above cut-off value, percentage not stated
6	Ercan 2011 [11]	longitudinal	Modular Analytics E 170 Module (Roche diagnostics), Basel, Switserland.	n = 30	<25	17.5 (median) 7.6 to 39.3 (range)	19.7 10.4 to 39	18.3 7 to 38.6	16% above cut-off value

SD, standard deviation; T, trimester.