My partner has had a merino coil fitted for last 5 years and normally only has very light spotting during her period. Her last 2 have been heavier requiring the use of sanitary towels. She appears to have had a bout of thrush last week due to being on a 2 week course of antibiotics with White / slightly yellow discharge and sore external genitals. She used canestan cream and took probiotic which seems to have at least cleared up the external soreness. She's not sure about the discharge as she is currently menstruating. Are there any STDs which cause heavier periods and if so which ones? Is heavier period a common symptoms of STDs, if not what could be the problem? Thanks