The advent of smartphones and apps in the 21st century, combined with the teachings of Paul VI in Humanae Vitae, has opened up a technological revolution in fertility awareness for achieving and postponing pregnancy in line with God’s plan for human love and relationships.

The Catholic Church played a critical role in developing fertility awareness methods -- thanks to a combination of papal leadership and courageous scientists -- throughout the 20th century. 

Now 50 years later, the Centers for Disease Control report that 30% have gone off hormonal contraception, and 1 out 5 women would use fertility-awareness methods to postpone pregnancy if they knew about them. 

Fertility-based awareness methods aim to help a couple approximate exactly as possible when a woman has ovulated in her cycle. This knowledge can help couples either to conceive a child, or postpone pregnancy. 

Today many Catholics are using apps with a variety of existing natural family planning methods, and new natural methods are emerging thanks to a combination of science and technology. 

This is a sample of some options out there with some short descriptions. Not all of them are Catholic-specific, but they can all be used in line with the Church’s teaching. 

The key is to find a certified Natural Family Planning instructor that can help a married couple discern and learn the method that works both for the woman, and for the couple.

KindaraThis app tracks a woman’s basal body temperature (BBT), cervical fluid, and has up to 50 custom fields for tracking fertility-related signs. The app also syncs with the blue-toothed based Wink BBT thermometer. The Users are able to draw upon Kindara’s educational resources and user community.

Marquette Fertility App (iOS and Android) - This app complements the Marquette method system, developed out of Marquette University, and has options for recording basal body temperature, cervical mucus, hormone strips, and information from the Clear Blue Easy fertility monitors.

DOT - Dynamic Optimal Timing - This app determines a woman’s high, medium or low chance of pregnancy each day based on her cycle lengths. The app claims to be effective tracking periods, and postponing or achieving pregnancy.  

Ovuview (Android only) - This app tracks and predicts a woman’s period, ovulation and fertility, by taking a woman’s cycle symptoms and interpreting them through 14 different sympto-thermal methods.

Fertility Friend - This is a fertility charting app that records fertility signs such as basal body temperature and cervical fluid, as well as other customizable signs. The app serves as a “dashboard” with tools, educational materials, and prediction models for future cycles.  

Ovia - Ovia is a family of apps covering fertility, pregnancy, and parenting. The Ovia fertility app has helpful information and charting inputs for couples trying to conceive, but also has a “not trying to conceive” mode for couples that fall in that category.

Femometer (iOS only) - This app aims to provide women with fertility information using machine learning algorithms, so that women with irregular cycles can use it as a health tracker. The app incorporates BBT temperatures and hormonal test strips. It also has a post-pill protocol, and auto-syncs with the Femometer Digital Basal Thermometer.

Lily - This app has two ways of evaluating information: there is an averages-based method, which is less accurate, and a sympto-thermal based method, which is highly accurate and applies various rules depending on the data from cervical mucus and daily temperatures. 

Natural Cycles - This app works on a sympto-thermal method, incorporates an algorithm to interpret a woman’s recorded daily temperature and determine a woman’s fertile window. The app was designed as a European contraceptive, but can be used for natural family planning by abstaining on “Red days” instead of following the recommendation to “use protection.”

FEMM (Fertility Education and Medical Management) - This highly customizable app is part of the FEMM system for health tracking, postponing pregnancy, and achieving pregnancy. A woman keeps track of her period, ovulation dates, basal body temperatures, physical or emotional symptoms, and other symptoms or categories as needed. FEMM teachers and doctors are available for added support.

Some NFP Facebook forums for more information: 

Unofficial Marquette NFP method support group

Fertility Care Creighton & NaPro User Support Group

NFP Support: Billings Ovulation Method

Natural Family Planning Support Group

Catholic Men's Sexuality (A male only group that regularly discusses NFP and other subjects)

Peter Jesserer Smith is a staff writer for the National Catholic Register, and a frequent contributor to Angelus News. 

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