Effects of Parity and Serum Prolactin Levels on the Incidence and Regression of DMBA-Induced Tumors in OFA hr/hr Rats

Table 2

Number and percentages of rats with and without mammary tumors in the three groups.

	Without; tumors	With; tumors	%	Regressed; tumors	%	Necrotic; tumors	%	Regular; tumors	%
Nulliparous	12	30	71.4	0	0	0	0	30	100
Pregnancy-lactation	35	47	57.3	17	36.2*	11	23.4*	19	40.4
Implanted	11	26	70.3	0	0	0	0	26	100

* 𝑃<0.05 compared to Nulliparous or Implanted rats.