Women in procreation mode can now sign up for a new series of text message alerts from BabyCenter.com reminding them just when the most opportune times are each month to attempt to get pregnant.

The new set of mobile fertility alerts, dubbed Booty Caller, are free to BabyCenter users who fill out some basic information on their menstrual cycles. BabyCenter then will deliver a total of 18 text messages (three per menstrual cycle), which provide women with information on just where things stand fertility-wise at that particular moment. For example, a message might read “Your fertile window opens today and lasts 5 more days.” BabyCenter will use Booty Caller to drive users to its mobile site for more information.

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