A Catholic guide to fertility monitors

One of the most controversial — and yet most important — Catholic teachings is the prohibition of artificial birth control. It is an integral part of the rich and beautiful tapestry of Catholic sexual ethics.

Of course, this prohibition doesn’t mean having as many children as physically possible. Catholics are called to practice a “responsible parenthood” characterized by “prudence and generosity,” and are invited to use Natural Family Planning (NFP) to prevent (or achieve) pregnancy. 

Even apart from Catholic teaching, there are countless reasons to use natural methods to prevent or achieve pregnancy. And, more broadly, it's important to track menstrual cycles for all of the crucial health information this tracking reveals.

A fertility monitor is one of several tools that women can use to track their cycles and better understand their overall health.

It’s key to keep in mind that technology should support — not replace — your personal awareness. If you want to use a monitor to track your cycles as well as to prevent or achieve pregnancy, it’s crucial to work with an instructor. You can learn more about the different types of NFP here.

“Be aware that fertility monitors are not one-size-fits-all,” said Elizabeth Bauer, PA-C MMSc, in an interview with Aleteia. 

Bauer teaches couples how to use The Marquette Method. As a member of Whole Mission, a collaborative of Catholic healthcare professionals seeking to provide high-quality health education to women and families, Bauer is one of the only instructors in the U.S. who offers Marquette Method instruction in both English and Spanish. 

Bauer recommended that couples always, always work with an NFP instructor. 

“It increases the effectiveness as the rules can be nuanced, and often couples misunderstand the theories and rules behind the method,” she said. “For example, a low on the monitor does not mean a low chance of conception.”

The right monitor depends on your specific needs and circumstances. Consult with an NFP instructor who can provide guidance aligned with your values while helping you find the right tools for your unique needs.

Here is a guide to a few of the most popular fertility monitors.

Basal body temperature (BBT) monitors track the subtle rise in temperature that occurs after ovulation. 

The Tempdrop, Oura Ring, and Ava Bracelet offer wearable options that measure while you sleep, eliminating the need for manual charting first thing in the morning. These devices sync with apps that analyze your patterns over time, making interpretation simpler.

The Clearblue Fertility Monitor and Mira track hormone changes in urine samples. These devices detect luteinizing hormone (LH) surges before ovulation and sometimes estrogen changes too. 

While effective, remember that they're designed primarily for achieving pregnancy, so you will need an individualized plan if you want to use them to avoid pregnancy (an instructor will help you there).

Really all that is needed to track cervical fluid is training in what to look for, so a monitor is not actually necessary. But if you find cervical fluid changes tricky to interpret, you may find it helpful to use a monitor like the Kegg to track changes in your fertility indicators.

These tools aren’t just for avoiding or achieving pregnancy. Monitors offer valuable insights into your overall health too. 

Irregular cycles might indicate thyroid issues, PCOS, or stress. Many women report that understanding their cycles helps them manage energy levels, mood fluctuations, and even migraine patterns.

These tools can help women to use new scientific research to honor your body's God-given design while understanding and improving your reproductive and overall health.