Heat transfer fluids comprising a polytrimethylene ether glycol or random polytrimethylene ether ester glycol, or mixtures thereof, and processes of using them in order to transfer heat. Further the methods and compositions improve gestational length and birth weight. Thereafter, the fracture sealing composition is squeezed into one or more natural fractures or into one or more new fractures formed in the well bore to thereby increase the pressure containment integrity of the well bore.