Is Plan B Birth Control?

Birth control? Plan B?
You mean the pill?
Or the implant?
Or the shot?
Wait, there’s another one?

It’s hard to keep up!

In recent years, the term birth control has become more and more of an ambiguous buzzword in women’s health. The more products and versions that come out, the more confusing it can be to keep them all straight. It’s no surprise that there are more forms of birth control than ever before in history because, well, there are simply more medications now than ever before. Whether it be in the form of an implant, a fertility tracking method, a shot in your arm, or a pill you take daily, birth control is very much accessible to women across the country. While there is something to be said for having so many options available to us, it’s easy to think of birth control as all sort of the same thing. Birth control methods have the same purpose: to potentially prevent pregnancy from happening at a certain point in your life. However, it is important to know that not all birth control products are created equally.

One distinction we want to highlight in today’s blog is the difference between a routine birth control pill and the plan B, or morning-after, pill. While these two products come in similar forms and packaging, they are different things in terms of what they do inside of your body.

Let’s start with the similarities…

Both are pills.
Both are taken in an attempt to prevent pregnancy.
Neither are 100% effective in preventing pregnancy.
Neither protect you from STDs (7). 
Both can cause similar side effects (nausea, vomiting, bloating, and irregular bleeding, just to name a few)

Now, how are they different?

Plan B/ The Morning-After Pill 

  • Emergency contraception 
    • This type of pill is not meant to be taken daily or as regular birth control (7). It is marketed as one pill you take in order to prevent pregnancy after having unprotected sex. It can have serious side effects on your natural menstrual cycle if taken over and over, as your body is exposed to more and more synthetic hormones (3) (more so than you would be exposed to naturally, or even with taking normal, routine birth control pills). 
    • Plan B does not provide long-term prevention of pregnancy. It works to potentially prevent pregnancy after only one act of unprotected sex or birth control failure (3).
  • The most common form is Plan B One-Step®. Both brand name and generic versions contain Levonorgestrel 1.5mg (1)
    • This dose of Levonorgestrel, which is more than 75% of the amount of levonorgestrel found in certain oral contraceptives (2), if taken before ovulation, has the capacity to block a surge of hormones that usually trigger ovulation (the release of an egg) to happen. It also has the capacity to make your cervical mucus thicker, making it harder for sperm to swim through, and has the capacity to make the lining of your uterus unsuitable for implantation and for a baby to grow and develop in. 
    • The exact mechanism of action (how the pill works in your body) is not fully understood (6) and is actually heavily debated, but what studies across the board agree on is that the pill works differently depending on what point in your cycle you take it (2). 
    • If taken before ovulation, levonorgestrel is said to delay ovulation (the monthly release of an egg from your ovaries) temporarily so there’s no egg to meet the sperm that may still be around to potentially fertilize the egg (4). The idea is no egg, no fertilization, and thus no pregnancy.
    • An important note: There is evidence that taking emergency contraception such as Plan B® or ella® can lead to the loss of an already fertilized embryo (meaning a sperm and egg have already combined to make a unique DNA set and human life has begun) that is not yet implanted in the uterus (8).Morning-after pills can alter the lining of the uterus and prevent implantation. Without the ability to implant, a human embryo will not survive. It is important to know if you are considering taking a morning-after pill  that the pill does carry a risk of the death of a fertilized embryo, a unique human life(2). 

  • There is also another form of the morning-after pill called ella®, or ulipristal acetate
    • This pill is chemically related to mifepristone (RU-486), the “abortion pill,” and acts to block progesterone. 
    • This pill may prevent ovulation and may reduce the chances that a human embryo would successfully survive and grow in the uterus. 
  • Both Plan B One-Step® and ella® may cause side effects of nausea, vomiting, irregular bleeding, cramping or abdominal pain, fatigue, headache, and dizziness (8) 
  • NOTE: Cramping or abdominal pain from the morning after pill can potentially mask the signs of an ectopic pregnancy, a potentially life-threatening condition in which a fertilized egg implants outside of the uterus. The morning-after-pill will not resolve or end an ectopic pregnancy. If you have severe abdominal pain 3-5 weeks after using the morning-after pill, or if you miss your next period , you should seek emergency or OB/GYN care to rule out a pregnancy (either ectopic or in the uterus) (8)

In comparison…

Birth Control Pills 
  • Routine contraception
  • Usually prescribed by your doctor (can sometimes be prescribed via telehealth) 
  • Picked up behind the counter like other prescription medication
  • Designed to be taken consistently every day 
  • There are several different types with different ratios of hormones (estrogen and progesterone being the key players)
  • Can cause a wider range of negative side effects due to the amount of variations there are 

The main takeaway from this post is that Plan B One-Step, or the morning-after pill, is not meant to be taken as a routine method of birth control. It is labeled as an emergency contraceptive tool, and it also carries the potential for a loss of a fertilized embryo before it is implanted.  

Also keep in mind, neither birth control pills nor emergency contraceptives carry 100% guarantees of preventing pregnancy, but they do pose risk of side effects. There are many other forms of birth control outside of these two, some of which are natural and do not carry the risk of certain side effects. If you are in need of options counseling or would like help identifying a local OBGYN to see, feel free to reach out to us at Paulding Pregnancy Services!

If you have further questions about this content, additional comments, or just something you’d like to share, feel free to drop it in the comment section below or reach out to We would love to connect with you and get you the trusted medical information you need to make educated decisions in regards to your health.
*The information contained in this blog is for educational and informative purposes only. No material on this site is intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice and care of your physician or other qualified healthcare provider with any questions you may have regarding a medical question or diagnosis.

  3. single mechanism of action,type of emergency contraceptive 19
  7. Plan B One-Step (levonorgestrel) Tablet (
  8. Vicki L. Dihle, PA-C. (2017). The Morning After Pill. Colorado Springs, CO; Focus On The Family.