Mercy Gynecologist Dr. Ann Peters Discusses Period Tracking Apps

July 24, 2019
The Institute for Gynecologic Care at Mercy - Baltimore, MD

Menstrual tracking apps have increased in popularity. Some are solely dedicated to women’s health while others are more general apps that have incorporated menstrual tracking into their features like Fitbit and Apple Watch. Ann Peters, M.D., M.S.,Minimally Invasive Gynecologic Surgeon with The Gynecology Center at Mercy Medical Center was interviewed recently by Good Housekeeping magazine about the nature and efficacy of menstrual period tracking apps. Here are her responses…

What are these apps good for?
Apps originally designed for ease of tracking one's menstrual calendar have expanded to not only help women track their period, but also help them improve timing of fertility or on the flip side natural family planning if they would like to avoid pregnancy. Most complex apps these days allow women to track their menstrual days (including flow amount and associate symptoms) as well as predict the next cycle, cervical mucous, fertility days, body temperature and may even include health articles and educational material for patients.

Can they actually tell you anything about your body and/or health?
These apps do make it much easier for patient to track abnormal menstrual cycles and allow them to take better control over their cycle and natural family planning if they would like to avoid any prescribed contraceptive methods. Fit bits and apple watches can track body temperatures that can also be imported into these apps which in turn allows women to track and predict when they may be ovulating or to maximize changes of pregnancy if they are hoping to conceive. Furthermore, patients can also import information on cervical mucous consistency which also changes throughout the month based on whether ovulation has occurred. The best method is something called symptothermal where apps take information about both and help women figure out if they have ovulated or are at risk of unintended pregnancy.

What are their limitations?
While there are no limitations to patient tracking their periods with a number of these applications, the accuracy of these applications in helping women determine whether they can use natural family planning methods using basal temperature and cervical mucous is in part based on the assumption that women have regular cycles and accurately follow their cycles for multiple month to ensure accurate readings. Hence if women cannot demonstrate that this is the case, these apps will not be able to accurately predict one's menstrual cycle, ovulation time, or window when a woman should avoid sex.

For women interested in using them, what are some tips for using them properly and getting the most out of what they offer?
The apps rely on the consumer to properly enter the appropriate data needed to make accurate predictions. If the user does not enter the correct information or the measurements are inaccurate (i.e. a women misjudges her cervical mucous consistency or her thermometer is inaccurate) women may be lead to believe that they are safe from unintended pregnancy when they are not. While perfect use of 'fertility awareness based methods (FABM) of contraception' which these apps are based on have been report to be as affective as preventing pregnancy in 99 out of 100 people in 1 year of use, the typical use shows that nearly 1 in 4 patients will get pregnant accidentally within one year due to improper use. Furthermore as mentioned above, it requires women to have regular cycle which not all women do and requires them to track their cycle and symptoms for multiple month before one can deem the method accurate as there are such large variations. Furthermore patients should be careful that the apps they purchase are actually FABM approved methods and follow appropriate methods for pregnancy prevention or fertility. A number of apps will report disclaimers that they are not intended for pregnancy prevention and hence should not be used for anything other than menstrual tracking.

If there are any good tracking apps out there, please let us know what they are!
- Sympto, LilyPro, Lady Cycle (online only, but app coming soon) (cycle, fertility, and natural family planning/FABM)
- Cycle beads (natural family planning - FABM only)

Ann Peters, M.D., MS, is an experienced gynecologist and surgeon in The Gynecology Center at Mercy Medical Center in Baltimore, MD. Dr. Peters is specially trained in the care of routine and complex gynecologic diagnoses. She focuses on the evaluation and treatment of a wide range of GYN conditions including: endometriosis, chronic pelvic pain, uterine bleeding and fibroids.


Dan Collins - Senior Director of Media Relations at Mercy Medical Center

Dan Collins, Senior Director of Media Relations

Email: dcollins@mdmercy.com Office: 410-332-9714 Cell: 410-375-7342

About Mercy

Founded in 1874, Mercy Medical Center is a university-affiliated medical facility named one of the top 100 hospitals in the U.S. by Thomson-Reuters with a national reputation for women’s health. Mercy is home to the nationally acclaimed Weinberg Center for Women’s Health and Medicine as well as the $400+ million, 20-story Mary Catherine Bunting Center. For more information visit Mercy online at www.mdmercy.com, Facebook, Twitter or call 1-800-MD-MERCY.

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