Defects in type V collagen due to mutations in COL5A1 and COL5A2 are the cause of the classical type (types I and II) of the heritable connective tissue disorder Ehler-Danlos syndrome that confers an increased risk for PTD if the fetus is affected, especially from pPROM [39-41]. This evidence concerns the gene COL5A2 and Ehlers-Danlos syndrome.