Health Info

panoramic closeup image of the front glass, offices, and entry to the Student Health Center

Birth Control Methods - POP

What is a progestin-only contraceptive pill or “POP”?

A progestin-only contraceptive or the “mini-pill” is one kind of birth control pill. Regular birth control pills contain two hormones: estrogen and progesterone. The mini-pill has only progesterone in it and is highly effective with a failure rate of 0.3 percent with perfect use and 9 percent with typical use.

How does the POP work?

The hormone causes the mucus between your cervix and uterus to
thicken which helps to block sperm from ascending into the uterus. It also causes the lining of the uterus to become thinner. Finally, the mini-pill can stop your body from releasing an egg, so fertilization cannot take place.

Starting POP:

Switching from Estrogen Containing Contraceptive Pills Skip the 7 inactive pills at the end of the pack and instead start the POP’s the day after the last active pill. Use a back-up method for the first 2 days.

First Day Start

Take the first pill on the first day of your period. Take one pill daily at the same time every day, even during your period. Use a back up method, such as condoms or spermicide for the first 2 days.

Today Start

Start the pill today. If you have had unprotected intercourse since your last period, perform a pregnancy test prior to starting the pill. If it is negative, start the pill today. Use another method of birth control such as condoms or spermicide for the first 2 days.

As soon as you finish one pack, begin the next one. Start your next pack even if you are still bleeding or have not started your period. Continue taking one pill every day.

Missing Pills

If you miss one POP take it as soon as you remember it, even if that means taking two pills in 1 day. If you are more than 3 hours late taking a POP, use a back-up method (condoms or spermicide) of birth control for the next 2 days.

Test Results and Advice Nurse

Missing Periods

Keep track of your periods while you take the POP. If you have more than 45 days with no period, then you may want to do a home pregnancy test or see your clinician for an exam and pregnancy test.




In an emergency go to Mount Nittany Medical Center or call 911 for an ambulance.

Test Results and Advice Nurse

Send secure message to advice nurse via the UHS website or call 814- 863-4463.


Appointments can be made online via the UHS website, by phone 814-863-0774, or in person. If you are unable to keep your appointment, please call or go online to cancel. Otherwise you will be charged for the visit.

This content is reviewed periodically and is subject to change as new health information becomes available. This information is intended to inform and educate and is not a replacement for medical evaluation, advice, diagnosis or treatment by a healthcare professional. Reviewed 11/11/15

Other Health Topics: Women’s Health | Sexual Health | Birth Control | Illegal Drug Use

back to top

Student Health Center | 814.865.6556 | Contact University Health Services