Season 5 opens in the year 1961, and Poplar is beginning to feel the winds of social change with the improvements in housing, sanitation and healthcare. But for the midwives and nuns of Nonnatus House, it’s business as usual, as they continue to care for the sick and bring new life into the world. Throughout the season, the midwives encounter complex and challenging medical cases, ranging from an outbreak of typhoid to the increase in lung cancer, a teenage pregnancy and a mother who…