Natural Family Planning: A Natural Birth Control Method 

There are many contraception options or “family planning” methods that couples use. The most common birth control methods that we hear about are birth control pills, condoms, and IUDs, however, there is another lesser-known method that is completely natural and has similar efficacy rates as other methods. This method is called natural family planning (or NFP). 

Natural family planning, which is sometimes also referred to as “fertility awareness”, is a way that a woman can monitor various fertility signals to determine the times of the month when she is most (or least) likely to become pregnant.  NFP can be used to both prevent and achieve pregnancy. This method is one of the safest ways to do so and is also a great method for those who have religious or other concerns with the use of contraceptives. 

*Although natural family planning is natural and safe, its effectiveness depends on how consistently the method is followed. NFP does not protect against STIs.

How NFP Works 

Natural family planning works by tracking the various phases of a woman’s cycle to give a clear map of when sex will lead to conception, and when it will not lead to conception. The tracking can be done simply by using a regular calendar or journal, however these days there are countless options available for easy tracking, such as phone apps and websites (many of which are available at no cost).

Menstrual Cycle Phases

The phases of the menstrual cycle are menstruation, the follicular phase, ovulation, and the luteal phase. In general, a woman could be fertile in any of these phases, however by diligently tracking these phases, a woman can find the times when she is most or least likely to become pregnant.


Menstruation, commonly referred to as a “period”, occurs only when a fertilized egg is not implanted in the uterus (this is why a missed period is typically one of the first signs of pregnancy). Menstruation consists of the shedding uterus lining, which causes a regular discharge of tissues and blood from the body. Bleeding can typically last 3-7 days.  

Follicular Phase

During the follicular phase, a hormone is released from the brain, which initiates the production of follicles on the surface of an ovary. These follicles are fluid-filled sacs that have the potential to mature into an egg, which will be released during ovulation. This phase also consists of the rebuilding of the uterine wall. Estrogen levels increase, which causes the lining of the uterus to thicken in preparation for pregnancy.


Ovulation is when a woman’s egg is released for fertilization. The actual time frame when an egg can be fertilized is only 12-24 hours, however sperm can live inside the uterus for 5-7 days, meaning the window in which a woman is fertile is still much longer than the ovulation phase. Ovulation occurs at around day 14 in an average cycle. 

Luteal Phase

The luteal phase occurs immediately after ovulation. It lasts from around day 15 to day 28.  This is when the egg travels down the fallopian tube and reaches the uterus. If fertilization occurs, the egg becomes implanted to the uterine wall at this time. If there is no fertilization, the phases start over again, with the shedding of the uterine lining. 

Natural Family Planning Methods

Conception can occur at varying times during each of the cycles above and there is no singular phase that promises complete “infertility”. However, by tracking her cycle using natural family planning methods, it becomes easier to understand when having sex is most likely to result in conception.

The Marquette Method

The Marquette Method of natural family planning consists of hormone testing using urine. It uses the Clearblue Fertility Monitor to track where in a cycle a woman is, and most importantly for conception, whether she has ovulated or not. This method is considered the most accurate method, with efficacy rates in the high 90s, however, the monitor and testing strips need to be purchased, which can deter some from choosing this option. 

The Creighton Model

The Creighton model relies on physical cues, such as changes to cervical fluids or mucus, in order to determine a woman’s fertility window. These observations and changes in menstrual patterns are tracked in order to tell where a woman is in her cycle and whether she has ovulated. 

The Basal Body Temperature Method

This method involves tracking your body temperature when you are fully at rest. This would be, in most cases, taking your temperature before you get out of bed in the morning. If temperature is taken at the same time, and under the same conditions each day, then slight changes will be noticed at different points during the cycle. This will allow a woman to see where she is in her cycle and determine if she is fertile. This method alone is not always the most effective due to changes in temperature that could be due to illness and other unrelated factors. 

The Symptothermal Method

This method is like a combination of the Creighton and the basal body temperature method. By tracking temperature, and observable changes, the woman can more accurately track her cycle. This leads to better outcomes, and less unexpected pregnancy. 

Is Natural Family Planning Right for Me?

Natural family planning is certainly a safe and natural way to plan or prevent pregnancy, but in order for it to work effectively, it does require tracking and consistent observation of any changes happening in your body. If done correctly, NFP is effective, but there is much room for error and an increased possibility of pregnancy if it is not followed and tracked consistently. 

If you are wondering if you’re pregnant or need to know how far along you are, please contact our team at Care Net Milwaukee.  All of our services are free and we want to support you as you make your pregnancy decision.  


Care Net has been serving Milwaukee area women since 1985 and through this blog, we hope to continue sharing with the greater community peace, hope, and information related to pregnancy.