Commander Sarah West was a headline appointment when she became the first female commander of a frontline warship in the 500-year history of the Royal Navy.
She described taking on the role as the greatest achievement of her career, adding: "I'm looking forward to taking HMS Portland on operations with a professional and focused team."
Earlier this year she said her work commitments made it difficult to have a relationship.
She told the Daily Mirror: "Years at sea probably explains why I'm single. But every person in the military makes sacrifices."
More top news
China's wild Panda population grew by 268 or 16.8% between 2003 and 2013 according to a nationwide survey on the highly endangered mammal.
Approaching Atlantic frontal systems will give a wet and windy night right across the UK with some heavy bursts of rain for everyone.
Police said 375 people attended a rally in Newcastle by the anti-Islam group Pegida, while 2000 people joined a counter-demonstration.