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A warning, this next story contains some explicit content. It's about SmartPhone apps that help people track their sexual activity. We're not talking about hookup apps for sex around the corner. Rather, these apps help you get pregnant. And they're becoming very popular. From member station KQED in San Francisco, Aarti Shahani reports.
AARTI SHAHANI, BYLINE: At Natural Resources, a baby store in San Francisco's Mission District, one mom is changing a diaper and Lorain Acosta is taking her first prenatal class. The 30-year-old is pregnant.
LORAIN ACOSTA: Fifteen weeks.
SHAHANI: While Acosta wants to give birth the old fashioned way, she got pregnant with the help of a very modern tool.
ACOSTA: I tracked my fertility using OvuView. I'm an Android user, so I like this app for Android.
SHAHANI: OvuView has more than 18,000 reviews in the app store and gets mostly five out of five stars. When a woman is ovulating, her body temperature at rest goes up a degree or so. The app asks you to log that temperature before getting out of bed every morning.
ACOSTA: It's synched with my alarm, so every day when my alarm went on the app showed (unintelligible).
SHAHANI: Acosta and her husband, Andre Sornellis, say the app made them feel more in control. The very month they wanted to conceive...
ACOSTA: It helped us and we got pregnant.
ANDRES ORNELAS: Right away.
SHAHANI: It told you when to have sex?
ACOSTA: It just told me when I was more fertile.
SHAHANI: Dozens of fertility self-tracking apps have popped up on the market in the last few years. I pull out my Smartphone to show the couple one recently released called Glow. Acosta reads off the screen as her husband listens.
ACOSTA: Did you have sex, emotional discomfort, sad, angry stress? Is it for fertility or for, like, sexual preferences or - I don't know.
ORNELAS: Yeah, I'm kind of curious what it does with the answers that you give it. Those seem like questions that I've never seen related to fertility.
SHAHANI: The founder of Glow, Max Levchin, is a computer scientist, the same one who helped start Paypal. Levchin says Glow is running a science experiment.
MAX LEVCHIN: Part of our responsibility here is to actually gather enough data to run a study and say, you know what, people conceive faster if they tried it on their back or not.
SHAHANI: Glow stores all its data on the cloud. Arguably, sexual position is more sensitive data than a credit card number and this app does not strip people's names from their responses. Levchin says that's a service. If a Glow app user needs to visit a fertility doctor...
LEVCHIN: You actually want to show up with a log that that person can understand. They can look at it and say, oh, you've been tracking your data. Let me tell you what your options are.
MARCELLE CEDARS: My goal when couples are early in the process is try to make things as simple and low stress as possible.
SHAHANI: Dr. Marcelle Cedars is a fertility specialist at the University of California San Francisco.
CEDARS: And the more sort of boxes you put around their sexuality, to me, tends to increase stress.
SHAHANI: Cedars says the women who choose to use fertility apps like Glow may not represent women in general and they may not tell the truth about their sexual activity. Cedars also says fertility apps have to be crystal clear about whom they cannot help. These apps assume a woman is ovulating regularly.
CEDARS: But if you're having periods every two to three months, you may not be ovulating at all. And so it seems like there need to be some windows saying, you know, maybe you should talk to your doctor.
SHAHANI: The Glow app is free. Founder Max Levchin says he's focused on getting new users. And Glow has a companion edition for the partner of the woman trying to conceive. Using data about her mood and ovulation, Glow makes suggestions like...
LEVCHIN: This might be an excellent time to send a bouquet of flowers or a spa trip or something like that.
SHAHANI: Is this integrated with Flowers.com or Hotels.com?
LEVCHIN: Not yet, but since I am on Yelp's board, I know exactly where to look for the best florists and spas and we actually talked about it early on when we were designing this thing.
ORNELAS: That is kind of creepy.
SHAHANI: That's the gut reaction of Andres Ornelas, the father to be from the baby store. Ornelas is a fan of self-tracking but doesn't want an app that intrudes on his marriage.
ORNELAS: If an app told me, oh, now it's that time of the month to buy flowers for your wife, then I feel like I'm not giving them the flowers. I feel the app is doing it for me.
SHAHANI: But the guy who always forgets to buy flowers, he might like that feature. Fertility apps are just in their infancy. The startup, Glow, hasn't even reached its first trimester. For NPR News, I'm Aarti Shahani in San Francisco. Transcript provided by NPR, Copyright NPR.