TORONTO - A Canadian study suggests one in five fertility and menstrual tracking apps contain serious errors that could misinform users about their chances of getting pregnant.

Toronto researchers assessed 140 iPhone apps based on the accuracy, usability and breadth of the tools and information provided.

The lead author of the study, published in the Journal of Obstetrics and Gynaecology Canada, says the quality of apps varied widely, but was low overall.

Rhonda Zwingerman of Mount Sinai Hospital says 31 of the apps contained inaccuracies that could put users at risk of unintended pregnancy or delayed conception.

She says some apps made false guarantees about their efficacy as a contraceptive tool or unscientific claims that intercourse on certain days could influence a baby's sex.

The physician says there was a lack of information for users dealing with infertility or irregular menstrual cycles.

This report by The Canadian Press was first published Jan. 6, 2020.

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