How Does Plan B Affect Your Body?

Even if you’re using protection, there’s always a chance that you could get pregnant. Perhaps you’re thinking about taking Plan B to avoid an unplanned pregnancy. It’s important to be aware of how Plan B could affect your body and what to do if it fails.


Today, we’re discussing Plan B — including how it works, the potential risks and side effects, and what to do if you still get pregnant after taking it. Keep reading to learn more!


How Does Plan B Work?

Plan B is a form of emergency contraception that aims to lower the risk of pregnancy by preventing or delaying ovulation[1]. It’s important to know that Plan B (and all other forms of emergency contraception) should not be used in place of regular birth control[1]. It should also be noted that Plan B tends to be less effective for women who weigh 165 pounds or more[2]


Is Plan B an Abortion Pill? Can Plan B Cause Miscarriage?

While they seem similar, Plan B and the abortion pill aren’t considered the same things. The difference is that the goal of Plan B is to delay ovulation or prevent fertilization, while the abortion pill ends a pregnancy that has already begun[1]


That being said, Plan B can prevent a fertilized egg from implanting into the uterus in rare cases[3]. The embryo never has the chance to develop into a viable pregnancy and is eventually miscarried.  


Does Plan B Have Side Effects?

It’s important to be aware of the potential side effects of Plan B so you can protect your health! Common side effects of Plan B include[1]:


  • Irregular periods
  • Dizziness
  • Headache
  • Fatigue
  • Cramps or abdominal pain 
  • Nausea or vomiting
  • Breast tenderness
  • Allergic reaction to levonorgestrel (a hormone found in Plan B)


Can Plan B Cause Irregular Periods?

As mentioned above, Plan B can cause irregular periods, which can be alarming if you’re concerned about an unplanned pregnancy. You may experience a delayed period (up to a week), heavier bleeding during your next period, or bleeding between periods[1].


If you experience bleeding or spotting for longer than a week or severe lower abdominal pain three to five weeks after taking Plan B, contact your healthcare provider immediately. These symptoms can indicate that you became pregnant, but a miscarriage or ectopic pregnancy has occurred[1].


What to Do if Plan B Fails

If you took Plan B but your period is delayed for more than three to four weeks, it may be a sign that it failed[1]. The next step is to determine whether or not you’re pregnant. Consider scheduling a free pregnancy test and free ultrasound at Esteem Women’s Center! 


If your results come back positive, don’t panic. Our compassionate client advocates are here to help you explore all of your pregnancy options so that you can make an informed and empowered decision! We will do everything we can to equip you to confidently take your next steps!


Don’t wait to get the care you deserve! To schedule your appointment, please call or text (904) 915-4357!



  1. Mayo Foundation for Medical Education and Research. (2022, June 3). Morning-after pill. Mayo Clinic. Retrieved from  
  2. Cleland, K., Raymond, E. G., Westley, E., & Trussell, J. (2014, December). Emergency contraception review: Evidence-based recommendations for clinicians. Clinical Obstetrics and Gynecology. Retrieved from  
  3. Embryocidal Potential of Modern Contraceptives. AAPLOG. (2020, January 15). Retrieved from


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