Table 4.

Geometric means of plasma prolactin by tertile level of plasma sex hormones and sex hormone-binding globulin among postmenopausal women, the Singapore Chinese Health Study

	n	Geometric meana	p value	% Difference (p value)†
Estrone, tertiles, pg/mL
< 21.66	146	7.54
21.66–< 30.6	149	7.06
≥ 30.6	145	6.42	0.016	− 14.8 (0.016)
Estradiol, tertiles, pg/mL
< 6.50	131	7.02
6.50–< 9.31	132	7.38
≥ 9.31	129	6.34	0.149	− 9.7 (0.146)
Free estradiol, tertiles, pg/mL
< 0.18	131	7.22
0.18–< 0.28	134	7.14
≥ 0.28	130	6.42	0.096	− 11.1 (0.094)
Testosterone, tertiles, pg/mL
< 15.85	146	6.60
15.85–< 24.38	151	7.52
≥ 24.38	145	6.94	0.4	5.3 (0.432)
SHBG, tertiles, nmol/mL
< 33.70	146	6.60
33.70–< 48.70	151	6.84
≥ 48.70	145	7.64	0.023	16.0 (0.023)
Androstenedione, tertiles, pg/mL
< 358.3	146	6.86
358.3–< 332.5	151	7.10
≥ 332.5	145	7.08	0.6	3.2 (0.631)

^aGeometric means are adjusted for age at blood draw and time since last meal

^†% Difference between third versus first tertile of sex hormones

Difference of mean prolactin levels among exposure categories was assessed by F statistics obtained from linear regression models