I think it becomes more an issue when you consider that in these apps, people likely also enter things like prescription medications they take, what kind of contraception they use, if any. Additionally, if this data is being sold to advertisers, and a user of the app becomes pregnant, it is possible that data could be used to determine that the user might be pregnant before they even know. This has the potential by itself to become an issue, especially for teens and in cultures where people take having sex outside of wedlock to extremes (as in responding violently to it) by starting to show that person and potentially their other family members on the same internet connection ads related to pregnancy/baby stuff