Missed Period While Taking Junel

In our latest question and answer, the pharmacist discusses whether or not Junel can cause you to miss your period and not be pregnant.


Hi, I am taking Junel Fe 1/20 which is a daily birth control pill. I am not taking any other medications with it, and am allergic to penicillin. I take my birth control regularly and on time. However, one of the side effects is that it causes me not to bleed during my placebo week. Am I still protected during the placebo week even though I do not bleed? I do not know whether or not I should be worried or need to take Plan B.

Asked by Britt On Sep 21, 2022

Answered by
Medical Content Reviewed By HelloPharmacist Staff

Published Sep 21, 2022
Last updated Sep 21, 2022

Key points

  • A common side effect of birth control pills is amenorrhea (i.e. missed periods). This can occur more often the longer you take them.
  • Nevertheless, it is important you take a pregnancy test to rule out pregnancy if you have missed your period and are sexually active.

Amenorrhea (absence of menstruation) is a fairly common side effect of oral contraceptive medications, which includes Junel. 

In fact, bleeding irregularities or the complete absence of menses occurs in 20-40% of individuals taking Junel birth control pills (e.g. Junel Fe 1/20, Junel Fe 1/35, etc...). While studies show that bleeding irregularities, such as spotting, decreases in frequency the longer you take birth control pills, the incidence rate of amenorrhea actually increases as you continue on the birth control pills.

For example, with Lo Loestrin Fe (a lower hormone dose Junel birth control product), the incidence of amenorrhea increased from 32% in Cycle 1 to 49% by Cycle 13. That's nearly 50% of individuals taking the birth control that don't experience menses and are not pregnant. Per the prescribing information:

Women who are not pregnant and use Lo Loestrin Fe may experience amenorrhea (absence of scheduled and unscheduled bleeding/spotting). In the clinical trial with Lo Loestrin Fe, the incidence of amenorrhea increased from 32% in Cycle 1 to 49% by Cycle 13. If scheduled (withdrawal) bleeding does not occur, consider the possibility of pregnancy.

Now, it is extremely important to remember that If menstruation doesn't occur (i.e. you don't have your period_ after finishing the active pills, it is always necessary that pregnancy be ruled out.

Be sure to take a pregnancy test or visit your doctor to confirm. If you are not pregnant, know that not having menses after finishing your active pills is fairly common and there don't appear to be any negative effects associated with it. Nevertheless, you should let you doctor know about what you are experiencing so you may be properly evaluated.

Final Words

You mentioned Plan B in your question. Plan B is intended as an emergency contraptive option to be taken within a few days of unprotected sex. It does not work if you are already pregnant and isn't something that you take if you've missed your period.

If you have been taking your birth control pills as directed, they are extremely effective in preventing pregnancy. It's more likely that you are simply experiencing a common side effect. Be sure to speak with your doctor so you can be evaluated.

Thanks for reaching out to us! Please do so again anytime.


  • Lo Loestrin Prescribing Information, AccessFDA
  • Amenorrhea following use of combined oral contraceptives, PubMed

About the Pharmacist

Dr. Brian Staiger, PharmD

Dr. Brian has been practicing pharmacy for over 11 years and has wide-ranging experiences in many different areas of the profession. From retail, clinical and administrative responsibilities, he's your knowledgeable and go-to source for all your pharmacy and medication-related questions! Feel free to send him an email at Hello@HelloPharmacist.com! You can also connect with Dr. Brian Staiger on LinkedIn.

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