Using a fertility tracking app alone won’t get you pregnant. But it can help you feel more control over the process of trying to conceive, and can help identify important patterns in your body.
I tested over four apps daily over the course of three months, and Glow came out on top due to ease of use, accuracy, and the amount of data it allows users to track. If you are trying to get pregnant, it tells you the optimal times to have sex; and the more you use it, the smarter it gets.
Women who are trying to get pregnant and aren’t satisfied with “just waiting for it to happen” or “letting nature take its course.” It’s also a reasonable option for women who aren’t “trying-trying” but have gone off birth control and want to learn more about what’s going on with their cycles.
Fertility tracking apps are the natural sister product of period-tracking apps, which started popping up at around the same time smartphones did. Yet women have been manually tracking their fertility in order to get pregnant (or avoid pregnancy) for, well, forever.
Fertility tracking can be as complicated a process as you want to make it, and this guide isn’t meant to serve as the last word or the ultimate source. If you want to learn about the process in an incredible amount of detail, you’ll want to check out the actual ultimate source: The encyclopedic Taking Charge of Your Fertility, which was first published in the 1990s and got a major update and revision for its 20th anniversary edition published in 2015.
Still, while it helps to be familiar with non-app-methods of fertility tracking (and the best apps incorporate data obtained by using these methods), you don’t have to be an expert to speed up, or at least streamline, the process of getting pregnant. What you do need to do is figure out when you are ovulating, and these apps help with just that.
iTunes lists dozens of ovulation-tracking apps and dozens more period-tracking apps. Almost all of them are free, and they all promise to do the same thing: to help you get pregnant or avoid pregnancy.
Still, there is a great deal of variation among these free apps. And since fertility tracking takes time, and needs to be done daily to ensure the highest accuracy, you don’t want to waste precious minutes with an app that’s inaccurate, buggy, or hard to use.
Fertility tracking is not necessarily a situation in which spending more (i.e., more than zero) gets you more. In some instances, you can shell out a few extra dollars to upgrade your app’s features and offerings (and I’ve discussed when that’s worth it, below). But our top pick happens to be free.
That said, if you want to achieve the utmost accuracy with your fertility tracking, you will need to shell out on a couple accessories: A basal thermometer, ovulation test strips, and (ultimately) pregnancy tests. The basal thermometer is a one-time cost, and you’ll need to use new ovulation test strips and pregnancy tests (duh) each cycle.
You need these things because the best fertility-tracking apps, including our top choice, take your own body’s patterns into account to improve their algorithms and generate recommendations that are best for you, specifically.
If you have a 28-day cycle (with Day 1 being the first day of your period), you would on average ovulate around day 14. But most women aren’t average. Cycles vary in length, and ovulation can occur on different days in your cycle. You may ovulate early, you may ovulate late, and this even changes a bit from month to month—even if you’ve always had a super-regular period.
I tested these apps for The NightLight because I was trying to get pregnant with my second child. With my first pregnancy, in 2013, I tracked my ovulation using a website (our “Also Great” choice, below), a basal thermometer (they’re under $10, and this one gets pretty good reviews) and ovulation test strips, and all of them indicated that I ovulated around Day 15 of my 29-day cycle.
This time around, there were a lot more smartphone apps available, and I wanted to see if they’d improve on my previous experience. I also wondered if my ovulation patterns were the same as they had been before my first pregnancy. It turns out they were slightly different — and knowing this helped me conceive on my third cycle of tracking.
I started by reading reviews of tons of fertility apps in the iTunes app store. I also searched for reviews and rundowns of fertility apps on the web—though it quickly became clear that few people have tested multiple fertility apps simultaneously or systematically.
Most of the apps were sub-par or were billed as “fertility apps” but actually just focused on period tracking (remember, to be a true fertility app, the app needs to let users log temperature, cervical mucus, and ovulation test results, among other ovulation-related things).
I narrowed my set of test apps down to four, and used each one daily—beginning on the day in July 2015 that I went off the pill, and ending in October 2015, when I got positive pregnancy tests several days in a row and missed my period. (I also had one very early miscarriage during this time, and have included more info on how this relates to fertility tracking apps, below.)
After three months of testing, I feel confident that Glow is the best fertility tracking app for most people.
Glow fulfills the basic standards of a fertility app: it lets you track temperature, cervical mucus, and cervical position, but it also does a lot more. The more you use the app, the more accurate it becomes; that’s why I felt confident that it was right when it told me, in my third month trying to conceive, that I was ovulating at least two days earlier than usual.
The app is free, looks good, works intuitively, and during our testing was bug-free. It has very active user forums, though I didn’t participate in them much. And because Glow has so many users, it can actually gain broader insights into fertility and incorporate that data back into its app. (Like: How directly women ovulate to moon cycles!)
Glow has a great notification system. A big part of fertility tracking is being consistent and remembering to do it every day, so push notifications are essential. Glow didn’t send out excess notifications, but when I got a push alert reminding me that it was my most fertile day, I paid attention.
Glow does have minor drawbacks. In my second month of tracking, I had a very early miscarriage—often referred to as a chemical pregnancy—before I’d even missed my period. (Essentially, I got two faint positive pregnancy tests, followed by negative tests the next day.) Glow doesn’t handle miscarriage in the context of pregnancy tracking very well; if you have one, it archives all of the previous data you’ve entered into the app, and no longer includes that data when making future predictions. (Glow’s pregnancy app, Nurture, includes a “healing path” for women who experience miscarriage further along in pregnancy.) I found our “Also Great” pick, Fertility Friend, better at handling a chemical pregnancy.
One other quibble: In Glow’s quest to keep users coming back to the app consistently, it provides daily “insights” from a variety of academic sources suggesting “simple ways to boost your health on a daily basis.” Some of these tips seemed more like clickbait than anything else; one, for instance, recommend avoiding caffeine if you’re trying to conceive, citing a Lancet paper from the 1980s as its source. But that claim was disproved in later studies. Tips are great, but not if they’re based on out-of-date information.
Glow gets 538 ratings [for the latest version] and 5 stars in Apple’s App Store. The Android version has nearly 35,000 ratings, averaging 4.6 stars. Reviewers praise Glow’s accuracy and interface. “This app will change the way you track and the way you think about your fertile window,” one reviewer wrote. “I have tried out 3+ fertility and period tracking apps and this one is superior because this company knows big data and how to apply it to their algorithms.”
In a review of the app for Gizmodo, Alissa Walker wrote about how Glow changed her conceptions of her cycle. “Right away I started to see patterns which surprised me. It turns out that even though I have a pretty average 29-day cycle, I ovulate really late, usually on day 17 or 18. Which means if I was going by the ‘typical’ day 14 ovulation most women experience, I would have been missing my fertile window completely. In fact, this is one of the biggest insights Glow has gleaned from their users...50 percent of women are incorrectly estimating their cycle by up to four days.”
Bedsider, an online birth control support network operated by the nonprofit National Campaign to Prevent Teen and Unplanned Pregnancy, rated Glow 4.5 out of 5 stars, the highest of any fertility app it reviewed, and recommended it for “the hardcore DIY fertility scientist inside of you who really wants to nail this thing down.”
If you want to get even more serious about tracking your fertility, you’ll want to check out Fertility Friend, an extremely in-depth fertility site that includes an app and a number of advanced proprietary features. The basic tools are free, but if you want access to the unique stuff—member forums, an “intercourse timing analyzer,” a giant searchable database of other members’ charts, and a lot more—you’ll need to pay for the VIP product, which is $10 for 30 days, $25 for 90 days, and $40 for 365 days (check the company’s Twitter feed for promo codes).
Fertility Friend’s mobile apps aren’t nearly as slick, intuitive, or easy-to-use as the others I tested, but the site’s paywalled content is unique and invaluable. For example, Fertility Friend used anonymized member data to examine, say, how likely you are to get a negative pregnancy test before a positive test. There are also busy member forums for women who are, for instance, trying to conceive after more than 12 months or trying to conceive through IVF.
Fertility Friend can be overwhelming to someone who’s just begun the process of trying to conceive: Many of its users are fertility-tracking pros who’ve used the site through multiple pregnancies, and a fair portion are struggling with fertility problems, so the site’s active message boards may provoke some anxiety if you’ve just started trying to get pregnant for the first time. However, I bought a Fertility Friend membership both times that I was trying to get pregnant, and found it helpful both times, with very supportive women in the forums.
In addition to Glow and Fertility Friend, I tested two other highly rated apps: Ovia and Kindara. Neither of these is bad, but I found both less intuitive and less easy-to-use than Glow. Ovia offers a “fertility score” of 0 to 10, while Kindara indicates fertility using a bar-and-star system and also won’t wager to tell you the exact day it thinks you ovulated until you’ve been using the app for months. Neither of those is straightforward or obvious as Glow’s system, which provides a percentage for how likely you are to get pregnant each day. And Glow’s messaging couldn’t be more direct; for instance: “Peak day is here! Our algorithm shows today is your most fertile day in this cycle, so it’s extremely important to have sexual intercourse today!”
Clue has gotten a lot of press and touts itself as both a period and ovulation tracker, but it’s not specifically geared toward women who are trying to get pregnant and, as such, lacks features that the other apps have, like cervical mucus tracking. There are plenty of other well-reviewed period-tracking apps, too, but again, if you want to get pregnant, you should download an app that focuses on that goal.
Fertility apps will continue to improve. Glow, our winner, was cofounded by PayPal cofounder Max Levchin, and the company has raised millions of dollars in funding — not a guarantee of its success, of course, but a good sign that the company will continue to roll out features and products. Glow has launched three other apps (for tracking reproductive health, pregnancy, and the baby once it’s born) and has added new features for men. (It takes two to get pregnant, after all.) And while all the apps are free for now, Glow plans to add premium paid features starting in March.
Companies are also working on wearables and connected devices to accompany their fertility-tracking apps. My basic BBT thermometer cost under $10, but this spring, Kindara is rolling out “Wink,” a basal thermometer that syncs with the Kindara app and will retail for $129. (The pitch is that you save time by not entering BBT data manually into the app.) A host of other products that use sensors to track BBT are also hitting the market, but we don’t recommend shelling out a couple hundred dollars just yet; for now, that cheapo thermometer works just fine.
Glow is the best fertility-tracking app for women who are trying to get pregnant, thanks to its ease of use, advanced data tracking, and large number of users. And it helped me get pregnant with my son, who’s due in July.
- FN, The cycle following the chemical pregnancy was the one in which I got a pregnancy that stuck. Also, in the cycle in which I got pregnant, I ovulated at least 2 days earlier than usual. Your normal ovulation patterns may be different after any type of miscarriage, and if you want to try to get pregnant again right away, fertility apps can be extra-helpful in identifying a change from your usual pattern.
- FN, You probably won’t be surprised to hear that the Internet is FULL of misleading, baseless information about fertility and pregnancy. I highly recommend Emily Oster’s data-driven book Expecting Better: Why the Conventional Pregnancy Wisdom is Wrong— And What You Really Need to Know to anybody who is pregnant or trying to conceive; it includes an entire section on conception.
- Taking Charge of Your Fertility, Amazon.com
- Alissa Walker, How An App Helped Me (And 20,000 Other Women) Get Pregnant, Gizmodo, 8/28/14
- Chelsey Delaney, 4 Apps for Tracking Your Fertility, Bedsider.org, 2/9/15
- Glow-Health Demystified, Glow.com