Facebook claims nothing in the valid warrants from law enforcement mentioned abortion and instead indicated officials were probing the case of a stillborn baby who was burned and buried.
Analysis of 25 of the most popular menstrual cycle tracker apps in the UK was carried out by ORCHA, an independent company which assesses health app safety for the NHS.
Data expert Mico Yuk says women need to take precautions to protect their privacy. Period tracking apps can trace sexual activity and whether or not women intend to become pregnant.