Difference in breast size between the first and third trimesters of pregnancy and changes in a woman’s body size, subcutaneous fat tissue, and biochemical parameters

The greatest changes in the breasts occur during pregnancy, but during this time the entire woman's body also undergoes specific modification, however, only a few articles discuss breast changes during pregnancy. We aimed to analyse the variation of breast volume in relation to body size, subcutaneous fat tissue and biochemical parameters during pregnancy. The same female (N = 83) was studied twice - in the first and third trimester of pregnancy. Breast volume was calculated according to the formula of Kramer&Drexler (1981). Breast volumes varied greatly both at the ca. 10th week (544-3500 cm³) and at ca. 35th week (689-3730 cm³) of pregnancy. Only 35-67% (depending on the trimester) of women's breast volume categories (small, medium, large) matched their body fat categories (lean, average, obese). Breast size was mainly related to skinfolds located on the trunk and upper limbs. The largest changes in body parameters occurred in the group of small-breasted and thin women. In addition, the greatest increase in high-density cholesterol during pregnancy was seen in women with medium to large breasts (which may represent a positive effect of pregnancy), but higher levels of low-density lipoprotein cholesterol in early pregnancy were associated with a higher likelihood of larger breasts.