Ethinyl estradiol and norgestimate: everything you need to know

last updated: Oct 06, 2020

8 min read

Since the dawn of time, people have been looking for ways to be in control of when they get pregnant. The ancient Egyptians suggested the use of various tinctures, tonics, and tablets to be taken by mouth or inserted into the vagina before sex in order to prevent pregnancy. The greatest philosophers of Ancient Greece suggested ingesting a range of substances that were not only ineffective but were actually quite dangerous. While condoms have been around for a long time, it wasn’t until the 1960s that modern birth control pills were first introduced (Connel, 1999).

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What are oral contraceptive pills (OCPs)?

Birth control pills (also known as oral contraceptive pills or OCPs) are pills that mimic the hormones your body would produce if you were pregnant, essentially preventing your ovaries from releasing another egg and preventing pregnancy. These medications contain either progesterone-only or a combination of estrogen and progesterone, in which case they’re called combined oral contraceptives (COCs) (Berg, 2015). 

Your menstrual cycle involves communication between your brain, your ovaries, and your uterus, which all work in harmony to allow for the release of an egg from the ovaries into the fallopian tubes. If the egg meets a sperm along the way, it might be fertilized, and if it is, it will travel down into the uterus, where it settles in and begins developing as an embryo.

If no embryo implants itself into the uterus, the body sheds the uterine lining as a menstrual period and prepares again for the next month. Throughout pregnancy, the body stops the ovaries from releasing eggs. Oral contraceptives send the same signal to the ovaries that pregnancy does, preventing the release of an egg and therefore preventing pregnancy (Berg, 2015). 

There are different types of hormonal birth control available.

  • There are progesterone-only options that work both by preventing ovulation and by changing cervical mucus to prevent pregnancy. Progesterone also has an effect on the lining of the uterus (known as the endometrium), making it less hospitable for implantation of a fertilized egg (Berg, 2015). 

  • Combination birth control contains estrogen and progesterone. While progesterone blocks ovulation, estrogen blocks something called “breakthrough bleeding,” which is when a person experiences vaginal bleeding in between periods while taking oral contraceptives (Berg, 2015). Progesterone-only options are available because some people cannot take estrogen, such as women who are nursing, as estrogen can increase the risk of blood clots just after you have a baby, and estrogen can reduce milk production. 

Hormonal contraceptives like COCs are available in numerous doses and forms (CDC, 2020): 

  • Pills that are taken at the same time each day to ensure consistent effect with no more than 24 hours between doses. 

  • The patch, which is a sticker you wear on your skin either on your abdomen, buttocks, upper arm, or upper back. You wear it for 21 days (sometimes wearing a new one every 7 days) and then remove it and leave it off for seven days. Then you put on a new one. 

  • A vaginal ring, which is inserted into the vagina, usually for 21 days at a time, and removed for seven days. 

  • An injection that you can receive in your buttocks or arm, typically administered once every three months. 

  • An IUD or intrauterine device is a small T-shaped device that is inserted into the uterus through the vagina and the cervix.

  • An implant is a thin rod that is placed under the skin (usually in the upper arm), which releases small amounts of hormones consistently over three years.

What are norgestimate and ethinyl estradiol?

Norgestimate is a type of progesterone, and ethinyl estradiol is a type of estrogen. These medications are used in combination to prevent pregnancy. There is a wide range of combinations of estrogen and progesterone on the market to prevent pregnancy, and these are called combined oral contraceptives or COCs.

The combination of norgestimate and ethinyl estradiol is available under a range of brand names, including Ortho Tri-Cyclen, Mononessa, and Previfem, among others. Since each type of estrogen/progesterone combination has slightly different effects, some people find that they need to try multiple types of birth control pills before they find one that is right for them. 

Oral contraceptives for the treatment of acne

If you’ve ever had acne, you might know what a bother it can be. Luckily, if you’re interested in taking oral contraceptives to prevent pregnancy, you might be able to “kill two birds with one stone,” so to speak. Combination oral contraceptives have been shown to improve moderate acne. While they’re not right for everyone, they are a good option for people over the age of 15 who have already had their first period and are looking for birth control in addition to acne treatment. 

In addition to its use in the prevention of pregnancy, ethinyl estradiol and norgestimate have been used off-label to treat the following conditions (UpToDate, n.d.): 

  • Abnormal uterine bleeding: This condition refers to menstrual bleeding that is abnormal in terms of how long it lasts, how much blood there is, or how frequently the bleeding occurs (Kaunitz, 2020). After your healthcare provider has done a range of tests to determine if there is a more serious underlying condition, they may prescribe combination oral contraceptives that can be used in some cases to regulate menstrual periods and alleviate abnormal uterine bleeding. 

  • Dysmenorrhea: While most people experience some discomfort during their periods, if this discomfort is recurrent, crampy, and painful and disturbs your ability to function, treatment may be in order. Because this condition, known as dysmenorrhea, can be a sign of an underlying condition, your healthcare provider may perform an evaluation. If there is no underlying condition, they may prescribe oral contraceptives, which can make the lining of the uterus thinner, making your periods lighter and alleviating the pain associated with getting your period (Smith, 2020). 

  • Hirsutism and acne: Hirsutism is another word for excessive hair growth, and it’s actually pretty common—found in around one out of every fifteen women of reproductive age. Hair growth is typically genetic, but hormones can play a role. While it’s common to have dark pubic and underarm hair, excessive dark and coarse hair growth on the lower abdomen, upper and lower back, and buttocks, especially in women who typically don’t have hair in those areas, can be a sign of an underlying hormonal condition. In some cases, the excessive hair growth on the body may be accompanied by hair loss on the scalp and even acne on the face, chest, or back. While this might seem more like a cosmetic problem and less like a medical problem, it can cause real emotional distress and even depression for some. In addition, it may be the only outward sign of a serious hormonal problem that can affect things like fertility. Your healthcare provider may run a series of tests to evaluate your hormones and, if it’s right for you, may prescribe oral contraceptive pills to balance your hormone levels (Barbieri, 2020). 

  • PCOS: Polycystic ovary syndrome is a condition in which the ovaries don’t release eggs. This can cause infertility, as well as a range of other problems, like an increased risk of developing diabetes, heart disease, and even cancer. The outward signs of this condition can include increased hair growth on the back, lower abdomen, and face, as well as acne, obesity, and irregular periods (Rosenfeld, 2020). If you are diagnosed with this condition, your healthcare provider may prescribe oral contraceptives to treat the condition. It’s important to note that the use of hormonal birth control pills in women who have obesity can increase the risk of blood clots (Barbieri, 2020).

Do I have to get my period every month?

In fact, you don’t. When birth control pills were first invented, the scientist that developed them wanted to make sure that women were really not pregnant while taking them. To do this, he integrated a “withdrawal” week during which patients stopped taking the medication, resulting in bleeding (Gross, 2019). 

And while there’s some evidence that getting your period can actually be a good thing, there’s other evidence that supports avoiding periods altogether if you’re not interested in getting pregnant. If you decide that you don’t want to get your period each month, talk to your healthcare provider about the various options available, like taking the pill continuously (Gross, 2019). 

Side effects of ethinyl estradiol and norgestimate 

US Boxed Warning Cigarette smoke and serious cardiovascular events: Cigarette smoking increases the risk of serious cardiovascular events from combination oral contraceptive (COC) use. This risk increases with age, particularly in women older than 35 years of age, and with the number of cigarettes smoked. For this reason, COCs are contraindicated in women who are older than 35 years of age and smoke.

Common side effects

Common side effects of combined oral contraceptives such as ethinyl estradiol and norgestimate include (UpToDate, n.d.):

  • Headache, severe headache, or migraine headaches

  • Nausea

  • Vomiting

  • Breakthrough bleeding

  • Nipple sensitivity/pain

  • Depression

  • Emotional lability

  • Mood changes

  • Nervousness

  • Acne 

  • Weight changes

  • Breast changes (growth, swelling, tenderness, pain, nipple discharge)

  • Bloating, breast-tenderness

While this list includes many of the more common side effects, it is not exhaustive. Speak with your healthcare provider if you experience other side effects while taking this birth control medication as another option may better suit you.

Serious side effects 

The use of estrogen-containing contraceptives can increase your risk of developing blood clots. If you experience leg pain or swelling, difficulty breathing, or chest pain while taking oral contraceptives, seek medical attention immediately, as this can be a life-threatening condition (Martinelli, 2003). 

Who should not take norgestimate and ethinyl estradiol? 

Do not take oral contraceptive medications if you have a history of blood clots (such as deep vein thrombosis or pulmonary embolisms) or if you have a condition that predisposes you to developing blood clots. In addition, you should not take these medications if you (UpToDate, n.d.): 

  • Have a history of breast cancer

  • Are nursing

  • Have a history of liver disease such as hepatitis C

  • Have a history of kidney disease

  • Have a history of liver tumors (benign or malignant)

  • Are pregnant or trying to conceive

  • Have undiagnosed abnormal uterine bleeding

  • Have a history of arterial or venous blood clots 

  • Have coronary artery disease

  • Have diabetes

  • Have clotting disorders (such as factor V Leiden)

  • Have a history of high blood pressure 

  • Have migraines, and you’re over the age of 35

  • Have ever experienced an arrhythmia

  • Are over the age of 35, and you smoke cigarettes

  • Have ever had an allergic reaction to any of the components

This list is not exhaustive. Consult with a healthcare professional before you decide to take oral contraceptives to see if they are right for you.

Medications that cannot be combined with ethinyl estradiol and norgestimate

If you are taking phenytoin medications such as fosphenytoin, they may reduce the ability of your oral contraceptive pills to prevent pregnancy. The same is true of St. John's wort and carbamazepine (brand name Tegretol). If you are taking medications such as dasabuvir for the treatment of hepatitis C, tell your healthcare provider before beginning combination birth control pills as they may increase your risk of liver damage. There are many other medications that cannot be combined with oral contraceptives. Be sure to seek medical advice before starting a new medication (MedlinePlus, n.d.). 

Dosages and cost of ethinyl estradiol and norgestimate:

The most common dosage forms of ethinyl estradiol and norgestimate are 0.035 mg of ethinyl estradiol and 0.25 mg of norgestimate that come in packs of 21 active tablets and seven inactive tablets. Generic versions of this medication are available for around $9 per month, and the average retail price is around $25 per month, depending on whether or not you have insurance and if that insurance covers birth control medications (GoodRx, n.d.). 

What are my options for birth control if I can’t take oral contraceptives?

Whether you’re not allowed to take them because of a history of blood clots, or you prefer not to take medications that contain hormones because of the potential side effects, there is a wide range of options available to help you prevent pregnancy. Your healthcare provider may recommend the use of non-hormonal birth control options such as an IUD (intrauterine device), which is a small t-shaped device that is inserted into the uterus through the cervix and creates an unfavorable environment for implantation, preventing pregnancy. 

Other options include condoms, which, when used properly, have the added benefit of preventing most sexually transmitted infections (STIs). While the rhythm method, which tries to estimate the date of ovulation and avoid sexual intercourse during ovulation, has been touted by some to be effective, sperm can survive for as long as 12 days (or more) in the female reproductive tract, meaning that it’s actually possible to get pregnant even if you do not have sex for almost two weeks prior to ovulation. Some estimates say that out of 100 women practicing this method (also known as “natural family planning”), 24 will become pregnant within a year, and therefore it is not a favorable way to avoid getting pregnant (Morrison, 1972; Klaus, 1982). 

It’s important to remember that while your healthcare provider can prescribe OCPs without performing a pelvic exam, it’s important to have regular checkups with your OB/GYN to screen for cervical cancer and check for STIs. While OCPs, when used correctly, are effective for preventing pregnancy, they do not protect against STIs such as chlamydia, syphilis, and gonorrhea, as well as conditions like HPV (human papillomavirus), which can contribute to the development of cervical cancer (UpToDate, n.d.). 


If you have any medical questions or concerns, please talk to your healthcare provider. The articles on Health Guide are underpinned by peer-reviewed research and information drawn from medical societies and governmental agencies. However, they are not a substitute for professional medical advice, diagnosis, or treatment.

How we reviewed this article

Every article on Health Guide goes through rigorous fact-checking by our team of medical reviewers. Our reviewers are trained medical professionals who ensure each article contains the most up-to-date information, and that medical details have been correctly interpreted by the writer.

Current version

October 06, 2020

Written by

Yael Cooperman, MD

Fact checked by

Mike Bohl, MD, MPH, ALM

About the medical reviewers

Yael Cooperman is a physician and works as a Senior Manager, Medical Content & Education at Ro.

Dr. Mike is a licensed physician and a former Director, Medical Content & Education at Ro.