(Bloomberg Business) — Having a baby isn't just expensivefor parents. Insurance companies spend $18,329 on the averagenatural birth in the U.S., and that cost goes up for Caesariansections, multiple births, pre-term deliveries, orcomplications.

Parents and insurers share an interest in healthy pregnanciesand lower medical costs, and early interventions can reducethe risk of complications. There's just one problem:Insurance companies don't know whenwomen conceive.

Medical claims for prenatal visits don't reach them untillate in pregnancy or even after delivery. “We might not know awoman is pregnant until three months after she’s givenbirth,” says Leah O’Donnell, a managing director at ZaffreInvestments, the venture capital arm of Blue Cross Blue Shield ofMassachusetts.

To change that, some companies are trying to reach womensooner, using smartphone apps that track fertility cycles andpregnancy milestones.

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Since February, the Massachusetts Blue Cross plan has beensending information to members who use fertility and pregnancy appsfrom a company called Ovuline. Zaffre led a $3.25 millioninvestment in Boston-based Ovuline on May 22. Blue Crossmembers who use the app can get personalized notices abouttheir health plan's benefits and information about diet,exercise, or other factors that affect maternalhealth.

Ovuline is part of a class of self-tracking apps forexpectant moms and couples trying toconceive. Users enter data on everything from thetiming of menstrual cycles to how often they feel babies kick.

Another app, called Due Date Plus, is working with health plans,including Aetna and the Wyoming state Medicaid program.

The startup behind Due Date Plus signed a deal this month tomarket the app to Medicaid agencies across the country throughXerox, which has health-information technology contractswith 38 states. And Text4baby, supported by governments andprivate insurers, sends women text messages throughout theirterms. The free service has been used by more than 850,000women since 2010.

Insurers want to use app data to increase theodds of healthy deliveries because the stakes are sohigh: "Having a baby in a NICU for a month can be amillion-dollar hospital bill," O'Donnell says.

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Health plans have tried additional waysto learn when their members get pregnant, suchas working with obstetricians and gynecologists,says Rebecca Owen, a health actuaryat the Society of Actuaries. The apps are new within thepast few years, and insurers are interested, even if it's stillunclear how effective they are.

No one has done a rigorous medical trial to determine whetherthe apps actually lead to healthier pregnancies or reduced medicalcosts. "The judgement is still out on it,” Owen says. "We justdon’t know yet how well they work."

Women opt into Ovuline's program by identifying Blue Crossof Massachusetts as their insurance company on one ofthe apps. The apps collect about 400 data points for eachuser, says Chief Executive Officer Paris Wallace.

Ovuline doesn’t share users’ data directly with insurers.Instead, the app contains information about the health plan'sbenefits, as well as customized responses based on the datawomen record on their phones.

If pregnant women report back or shoulder pain, for example,Ovuline might tell them that their health plan coverspre-natal massages. Wallace says the system can also lower the riskof costly problems. If a woman reports rising blood pressure,dark urine, and a headache, the app recognizes the pattern as asign of preeclampsia, a potentially seriouscomplication. Ovuline doesn’t make a diagnosis, but the appprompts users to alert their medical providers aboutsymptoms.

Wallace says Ovuline has sent out 100,000 such alerts. “We’rebasically able to do massive triage on millions of people at thesame time,” he says. The apps, called Ovia Fertility and OviaPregnancy, launched in 2012 and 2013, respectively. Combined,they've had about 2 million users.

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State Medicaid plans are watching Due Date Plus' deployment inWyoming carefully, says Brett Jakovac, managing directorof Xerox's government healthcare business. "We’re getting anincredible amount of interest and we’re expecting we’re going tosee a number signing up," he says.

Maternity care is a top cost forMedicaid programs. In Wyoming, Due Date Plus connects Medicaidpatients with nurses or care managers who may visit them at home.Users who report smoking can be connected to a counseloror enroll in an online smoking-cessation program.

According to Wildflower Health CEO Leah Sparks, even generallyhealthy women may benefit from the app. “There are things thatcome up in pregnancy that even the most savvy, high-tech, motivatedSilicon Valley mom may not be aware of,” she says.

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