Mrs Patel is a 53 year old female who is getting increasingly distressed by episodes of urinary leakage. Her symptoms first started soon after the birth of her fourth child although in the last few weeks she has had more frequent episodes. Mrs Patel explains that these episodes aren’t triggered by anything in particular. She suddenly gets the urge to pass urine and isn’t able to get to the toilet quickly enough. She is also waking at night to pass urine.
What is the most suitable initial treatment for her?