In this contribution we will shortly review the main mechanism through which
primordial magnetic fields may affect the electroweak baryogenesis. It is shown
that although strong magnetic fields might enhance the strength of the
electroweak phase transition, no benefit is found for baryogenesis once the
effect of the field on the sphaleron rate is taken into account. The possible
role of hypermagnetic helicity for the electroweak baryogenesis is shortly
discussed.Comment: 10 pages, 1 fig. Plenary talk presented at the COSMO99 Conference,
Trieste, Italy, 27 Sept - 3 Oct, 199
