The mechanical properties of piping materials in gaseous hydrogen environments are still a complex subject, although steel pipelines have been a major means of transporting gaseous hydrogen for decades. An assessment of the material performance in gaseous hydrogen environments is necessary for safe and reliable pipeline design and operation, not only for existing pipelines but also for new pipelines needed to accommodate future consumption demands. Since the materials for hydrogen pipelines are usually subjected to the repeated loading of pressure fluctuations, fatigue crack growth in steels in gaseous hydrogen is of paramount concern. In this paper, the current understanding of the effects of hydrogen on fatigue crack growth are reviewed. In particular, the effects of various parameters, such as steel grade, loading frequency, stress ratio, and hydrogen partial pressure are discussed in detail. Moreover, fatigue crack growth analyses in hypothetical hydrogen pipelines using a fatigue crack growth model developed by the Institution of Gas Engineers and Managers (IGEM) are presented. These analyses are used to assess the applicability of conventional pipeline steels, and their results indicate certain technical challenges for the industry.