In the US, hospitals are moving rapidly toward a BSN-only RN staff. This is being driven by a number of factors, including evidence of improved patient safety & quality outcomes with higher percentages of BSNs. It is not a "trend", but an evidence-based and deliberate movement that is an important aspect of improving the quality and effectiveness of acute care services. If you are just starting your nursing education, and wish to work in an acute care (hospital) setting - yes, you will need a BSN. IN the US, OB services are tied to acute care, so you will need a BSN to work with that population.
Acute care is not the only environment in which nursing care is delivered.... There will still be opportunities for all levels of nursing in non-acute care settings.