One in five fertility and menstrual tracking apps contain serious errors that could misinform users about their chances of getting pregnant. Toronto researchers rated each with a score out of 100 based on the accuracy, usability and breadth of the tools and information available. Lead author Rhonda Zwingerman said the quality of apps varied widely, but was low overall with an average score of 32.5 per cent. While better than traditional pen-and-paper period planning, users should be wary of relying on their smartphone when making decisions about their reproductive health. Researchers gave 31 apps a failing score of zero because they contained inaccuracies that could potentially harm users. Zwingerman says many apps made unfounded scientific claims, including false guarantees about their efficacy as contraceptive tools. At least 15 of the apps had "gender prediction" features suggesting that factors such as having intercourse on certain days could influence a baby's sex. According to the study, the
majority of apps appeared to be backed by developers and tech companies rather than health-care professionals. Zwingerman said most menstrual tracking apps use overly simplistic predictions, which could give users a false sense of ease when they need to see a doctor. Only 18 per cent of the apps contained a feature related to infertility or fertility treatment.