Measurement of breast volume by ultrasound during normal menstrual cycles and with oral contraceptive use.

The volume of the human breast was measured by ultrasonographic methods with good reliability and reproducibility. Variations in breast volume of up to 36% were encountered with weekly measurements during the course of seven normal menstrual cycles. Oral contraceptives containing 35 to 50 micrograms ethynyl estradiol and amounts of norethindrone varying over a range of 0.4 to 2.5 mg/day and used for six cycles did not produce dose-related changes in breast volume as compared with untreated control subjects, but the sensitivity of the experiment was reduced by notable individual variation and relatively small sample sizes.