Abstract: An HPC composition and method of treatment for the prevention of PTB and improved neonatal outcomes. The invention provides for a dosing regimen beginning as early as 14 weeks of fetal gestation and dosing regimens of a duration of as much as 25 weeks. The invention provides a high level of exogeneous progestin to endogenous progesterone when it is most needed. The instant invention consistently achieves active levels of HPC which achieve effectiveness. Exemplary dosing regimens comprise an oral administration of HPC in the range of 1,200 mg to 1600 mg, wherein the HPC is administered via a once a day, twice a day, or three times a day administration.