The solubility parameters of a range of saturated hydrocarbons were calculated from vapor pressures and heats of vaporization. Solubilities of testosterone propionate were determined in these solvents at 25 degrees and yielded solute solubility parameters which varied from solvent to solvent. The solubility parameter of testosterone propionate was determined by several other methods, and support was found for the previously published figure of cal(1/2) cm(-3/2). The geometric mean coefficient (l(12)) in saturated hydrocarbons was found to be a rectilinear function of the branching ratio (r). The mean l(12) of androstanolone and testosterone propionates was used to calculate the solubilities of other esters, giving good agreement with experimental results. IR data, presented as the sum of the shifts of the 3-keto and 17-ester carbonyl stretching frequencies in polar solvents, correlated rectilinearly with the geometric mean coefficients and the plot extrapolated to the l(12) value of n-hexane, calculated from the branching ratio plot. Attempts to predict solubilities of other esters in polar solvents using l(12) values achieved only limited success.
Pregnancy and childbirth greatly alter the levels of hormones in the body. These changes in hormones can in turn trigger changes in hair growth.  During pregnancy, your hair will remain in the growth or transitional stages, so it becomes much thicker with hair that would normally have stopped growing or fallen out. About three months following delivery, your hair will resume falling out, and all the hair that would have fallen out during your pregnancy may fall out quite suddenly. Rest assured that this is normal and temporary, and that this rate of hair loss will not continue. Take care of your hair and treat it gently while you wait for your normal hair growth to return.