When Tonya Whitfield's cell phone buzzes with a text message, it could be a few words from a friend, a note from work -- or a reminder that it's time to grab her husband.
That's a message from the folks at babycenter.com. Give the Web site the details of your menstrual cycle and it will send you messages advising when it's, well, time.
The free service is called, appropriately, "Booty Caller." Its motto: "We tell you when, you decide where."
"It takes a lot of stress off," said Ms. Whitfield, 32, of the Philadelphia area, who found an ovulation prediction kit too much work and too unsexy. "This just texts you. I think it's kind of cool."
The Digital Age has reached another milestone: Where once it was our computer calendars that buzzed us to let us know when we had a lunch date or a meeting, now our cell phones are doing the job. These hand-held gadgets carry stacks of our favorite compact discs and calculate our daily meals and calorie intake. So why not add sex to the mix?
"The world of technology is increasingly becoming our environment. It's a sea change in society. We don't know where it will end up," said Frank Farley, a psychology professor at Temple University who says he gets text messages from a flower company any time a significant birthday or anniversary approaches. "Some people say, 'This is great. It's so helpful. We've been having so much trouble conceiving ...,' but how far does it go?"
Mr. Farley says young people today are "digital natives," born into a technological world. Older people are "digital immigrants," trying to find their way. And it looks like the divide will get even wider: An expectant father in New York developed the Kickbee, a stretchable band with embedded sensors that sends a message via the social networking site Twitter when his unborn child kicks his wife -- essentially, chatting from the womb. (See portfolio.menscher.com/itp/kickbee/).
Since babycenter.com started offering Booty Caller in November, thousands of users have signed up to get its monthly reminders, said Linda Murray, editor in chief for the San Francisco-based Web site, a global parenting network that has 7 million users worldwide and appears in eight languages. The service is very accurate for those who have regular menstrual cycles, and can be adjusted for those with irregular cycles, Ms. Murray said.
While there are many ovulation calculators online (thebump.com -- a popular affiliate of wedding Web site theknot.com -- calculates the best time to conceive), a service that reminds you via text messages is likely the first of its kind.
In many ways, Booty Caller is an extension of natural family planning: charting one's cycles to avoid or seek pregnancy.
So far, no user has informed the Web site that a Booty Caller baby is en route, but Ms. Murray is hopeful.
"There are a fair number of people in our audience who are actively trying to have a baby. It's almost a job for them. We thought this would be some fun," Murray said.
It's also a convenience in today's hectic world, Ms. Murray said, especially for those who already have children and are trying to conceive again. At the same time the Web site launched Booty Caller for its preconception audience, it also developed a way to send weekly pregnancy tips via mobile phone to expectant mothers.
"We're really trying to think what Mom wants on the go and what applications work on the phone," Ms. Murray said.
Once a user registers, Booty Caller sends fertility notices to one or both partners for six months, sending three texts per menstrual cycle. The first pops up the week before the woman's most fertile period starts and the final one is a last-chance message, "Today is your last fertile day! If you get pregnant during this cycle, your due date will be on or around [insert date here]."
The "Just do it" messages sometimes contain handy tips as well, advising users to take their vitamins, eat healthy foods, perhaps get a massage to stay relaxed, and, for goodness' sake, keep those men out of the hot tub.
"Every little bit helps," said Ms. Whitfield, who recently got the hot-tub message.
Married to husband Terrance for almost two years, Ms. Whitfield has miscarried three times. She decided to try Booty Caller last month. She was excited by the idea.
"I never knew you had five fertile days when you ovulate. It never really dawned on me," said Ms. Whitfield, a youth detention counselor.
Of course, sex isn't a robotic exercise that can be controlled by the clock or the text message. Mr. Farley thinks couples struggling to conceive should remember that the end justifies the means.
"You can still dress that up -- or undress, so to speak -- with enthusiasm even though you're both aware you're doing it on a schedule," Farley said. "Focus more on the thrill and the excitement of the possible outcome, which is to have the most wonderful thing in the whole wide world: a child. That goal becomes tremendously motivating. When you think along those lines, you can still have great sex, even on a schedule."
Some Booty Caller users say a reminder from the service can ignite a sexy back-and-forth via text messaging. Ms. Whitfield has it arranged so only she knows when the time has come.
"I don't call him," she said. "I just wait till we get home and go from there."
Post-Gazette movie editor Barbara Vancheri can be reached at firstname.lastname@example.org or 412-263-1632.