Clinical effectiveness

NC° Birth Control’s effectiveness and safety has been demonstrated across 10 peer-reviewed clinical studies, including one of the largest analyses of its kind. The real life effectiveness of the method remains inline with published rates.

NC° Birth Control Pearl Index

7 out of 100 became pregnant within one year

5 from incorrect use (unprotected intercourse on fertile days)

2 despite perfect use

of which 0.5 from app incorrectly identifying a non-fertile day

How NC° Birth Control works

The AI-enhanced algorithm behind the app confirms each user’s daily fertility status by analyzing temperature data, menstrual data & optional LH tests. To prevent pregnancy, users agree to abstain or use protection on fertile days.

How biometric data is collected

Data auto-syncs to the Natural Cycles app

NC° Thermometer

Measure upon waking, sync via Bluetooth

Oura Ring

Monitors temperature trends during sleep

Apple Watch

Monitors temperature trends during sleep

Patient eligibility

NC° Birth Control may be a good option for those seeking a non-hormonal, non-invasive birth control method.

NC° Birth Control is suitable for those who:

  • Are 18 years or older
  • Agree to use protection or abstain on fertile days
  • Cannot tolerate hormonal contraception
  • Currently use a period tracker or less effective method

Comparison of contraceptive effectiveness data

NC° Birth Control is more effective than calendar-based FABMs and is in the same effectiveness category as the pill.

Natural Cycles App
NC° Birth Control
93% Typical use
98% Perfect use
Typical use
Perfect use
Copper iud
IUD
>99%Typical use
>99%Perfect use
Birth Control Pill
Contraceptive pill
93%Typical use
>99%Perfect use
Natural Cycles App
Natural Cycles°
93%Typical use
98%Perfect use
illustration of a male condom
Male condom
87%Typical use
98%Perfect use
hand with crossed fingers
Pull out method
80%Typical use
96%Perfect use
Calendar Method
Calendar method
88%Typical use
95%Perfect use

Percentage of typical/perfect users who did not get pregnant with the method over one year of use. Reference: Contraceptive Technology (Table 5-2). 22nd Edition, 2023

Meet the NC° Medical Advisory Board

Access educational resources

Download printable resources developed by the Natural Cycles Medical & Science Team.

Backed by research

Our dedicated on-staff Medical & Research Team has published over 20 peer-reviewed studies, advancing our mission to empower women and further the field of female health.

Get in touch with a medical expert

Contact us about potential partnerships or research collaborations, to get more information, or to access a demo.

Dr Kerry Klaus
Dr. Kerry Krauss OB-GYN & Senior Medical Advisor for Natural Cycles

Add your details here and we'll get in contact.

Want to learn more about a hormone-free future?

Subscribe to our newsletter for access to our latest articles, exclusive promotions and more.