Table 5 Summary of results from previous studies of parental ages and breast cancer development

Cohort study

Colditz et al, 1991

US

118,309 (1,976)

3055

≥39 vs. <20

0.9 (0.56–1.45)

≥39 vs. <20

0.9 (0.57–1.39)

YES

YES

-

Zhang et al, 1995

US

2,662 (149)

29–62

≥36 vs. <29

0.8 (0.5–1.4)

26–31 vs. <26

1.5 (1.0–2.4)

-

YES

-

Holmberg et al¹, 1995

US

384,769 (1,967)

-

≥45 vs. <20

0.8 (0.48–1.28)

≥45 vs. <20

1.3 (0.85–1.98)

-

YES

-

Hemminki et al, 1999

Sweden

3,800,000 (8,877)

15–53

40–49 vs. <25

1.1 (0.94–1.18)

40–49 vs. <20

1.1 (0.91–1.27)

YES

-

PA in sporadic cases

Hilakivi-Clarke et al, 2001

Finland

3,447 (177)

-

-

-

-

NS

-

-

-

Study

Country

Cases/controls

Age (yrs)

Paternal age (PA)

OR

Maternal age (MA)

OR

Remark

Mutually*

Covariates^†

Case-control study

Standfast et al, 1967

US

229/229

40–44

-

-

29.1 vs. 28.2

²p < 0.05

-

-

-

Henderson et al, 1974

US

308/308

<64

31.5 vs. 30.7

NS

27.3 vs. 26.3

P < 0.01

-

-

-

Rothman et al, 1980

International

4339/12760

-

-

-

35–39 vs. <20

1.30

-

YES

-

Baron et al, 1984

UK

971/971

≤50

-

-

21–25 vs. ≤20

1.4 (0.92–2.18)

-

YES

-

Le Marchand et al, 1988

US

153/461

<45

36–59 vs. 19–26

1.4 (0.81–2.41)

30–46 vs. 23–26

1.7 (0.99–2.78)

-

-

Pts <33 yrs

Janerich et al, 1989

US

801/2647

-

Per 10-yrs

1.2 (1.07–1.33)

Each 10-yrs

1.2 (1.09–1.41)

-

-

-

Thompson et al, 1990

US

2492/2687

20–54

-

-

35–39 vs. <20

1.5 (1.10–1.93)

-

YES

parous

Hsieh et al, 1991

International

927/2616

≥35

-

-

Each 5-yrs

1.1 (1.01–1.10)

-

YES

postmenopause

Ekbom et al, 1992

Sweden

458/1197

≥35

-

-

Each 5-yrs

1.0 (0.92–1.12)

-

-

-

Janerich et al, 1994

US

2414/9138

-

≥45 vs. <25

1.0 (0.76–1.28)

≥40 vs. <20

1.1 (0.87–1.37)

-

YES

-

Sanderson et al, 1995

US

1147/1399

21–45, 50–64

-

-

≥35 vs. <25

1.0 (0.7–1.4), 1.0 (0.7–1.5)

-

-

-

Ekbom et al, 1997

Sweden

1068/2727

-

-

-

Each 5-yrs

1.1 (0.99–1.14)

-

-

-

Newcomb et al, 1997

US

1253/1121

-

≥40 vs. ≤24

0.9 (0.68–1.24)

≥40 vs. ≤20

0.9 (0.62–1.37)

-

YES

-

Weiss et al, 1997

US

2173/1990

20–55

-

-

≥35 vs. <20

0.9 (0.7–1.3)

-

YES

-

Innes et al, 2000

US

484/2870

14–37

≥40 vs. 25–29

1.5 (1.03–2.23)

≥35 vs. 20–24

1.9 (1.18–3.18)

YES

-

-

Titus-Ernstoff et al, 2002

US

5629/5928

50–79

-

-

≥40 vs. 25–29

1.3 (0.90–1.79)

-

-

postmenopause

Mellemkjǽr et al, 2003

Denmark

881/3423

<40

-

-

≥30 vs. <25

1.1 (0.90–1.36)

-

-

-

Hodgson et al, 2004

US

280/236

18–74

35–56 vs. 23–27

1.5 (0.7–3.2)

≥23–27 vs. 19–22

3.5 (2.0–5.9)

YES

-

PA in African American