Table 2.

Menstrual volume before and after treatment ($\overline{x}$ ± s, ml).

Groups	n	Before treatment	3 months after treatment	6 months after treatment	12 months after treatment
Observation	41	171.78 ± 40.40	80.37 ± 13.77∗	48.98 ± 16.58∗a	48.29 ± 15.29∗a
Control	44	172.50 ± 36.48	81.23 ± 17.22∗	70.93 ± 24.16∗a	70.02 ± 22.81∗a
t value		0.086	3.398	4.526	4.244
Pvalue		0.931	0.800	<0.001	<0.001

^∗ indicates significant differences (P < 0.05) compared to before treatment; a indicates significant differences (P < 0.05) compared to 3 months of treatment; b indicates significant differences (P < 0.05) compared to 6 months of treatment.