This story is great. A guy went on reddit to ask questions about his wife's fitbit. He thought there was something wrong with the sensor. Her heartrate was showing that she spent 10 hours in the fat burning zone and she hadn't been working out that much. Turns out, her high heartrate meant she was pregnant. http://bit.ly/1KdUpAN

Do you wear a fitbit? Have you noticed changes on it since becoming pregnant?