• Samantha Kerester, MD
  • Sarah Fetterolf, MD
  • Colleen Denny, MD
  • Danielle Wright, MD


  • Jonathan Kobles, MD


The State of Unintended Pregnancy in the United States 

  • Nearly half of all pregnancies in the United States are unintended, and more than one-third of these pregnancies, totaling approximately one million, end in elective abortion.
  • Unintended pregnancy disproportionately affects women:
      • Between the ages of 18 to 24
      • From marginalized and historically underrepresented groups
      • From economically disadvantaged backgrounds
  • Emergency medicine providers have the opportunity to provide sexual health education and increase contraceptive access for underserved patient populations who would otherwise have limited access to comprehensive contraception counseling and resources.




Combined Hormonal (Estrogen + Progesterone) Contraception

  • Progesterone thickens the cervical mucus and suppresses Gonadotropin-Releasing Hormone (GnRH), subsequently inhibiting Luteinizing Hormone (LH) to prevent ovulation and Follicle-Stimulating Hormone (FSH) to prevent follicle development. Estrogen further inhibits FSH and provides improved menstrual bleeding patterns. 
  • Combined hormonal contraception methods are 92-98% effective in preventing pregnancy. 
  • Patients may experience additional benefits which include shorter and more regular periods, decreased period-related pain, decreased menstrual blood loss, suppression of endometriosis, prevention of functional ovarian cysts, and improved acne. 
  • There are currently three methods available for combined hormonal contraception: 
      • combined oral contraceptive pills 
      • transdermal patch 
      • vaginal ring 


Oral Contraceptive Pills

The pill is taken every day for three weeks (or for longer in an extended pill pack), and then either a placebo or low-dose pill is taken for one week to allow menstruation. If only one pill is missed, the patient should take the pill as soon as possible and take the next one at the usual time. Backup or emergency contraception is needed only if two or more pills are missed. 

Dosing guidelines:

  • Formulations:
    • Monophasic: contains the same dose of estrogen and progestin in each of the hormonally active pills out of a 28 day cycle. Examples include Junel Fe 24 and Sprintec 28.
    • Multiphasic (biphasic or triphasic): contains different doses of estrogen and progestin each of the hormonally active pills out of a 28 day cycle (the doses increase over the three weeks). Examples include Tri-Lo Sprintec and Tri Sprintec.
    • Estrogen (ethinyl estradiol) dosing is typically 10-35 mcg/pill
    • Progestin dosing is typically 0.1-3 mg/pill
  • Dosing regimens:
    • Cyclic (21/7 regimen): provide hormone pills (monophasic, biphasic, or triphasic) for 21 days out of a 28-day cycle, followed by 7 days of placebo pills. The placebo pills at the end of the cycle allow for breakthrough bleeding, to mimic a menstrual period. This method is prescribed more often to reassure the patient that they are not pregnant.
    • Continuous: patient takes a combined estrogen-progestin pill every day for a year.
    • Extended (84/7 regimen): patient takes a combined estrogen-progestin pill every day, but 7-day intervals of placebo or low-dose estrogen pills are taken approximately every three months.


Contraceptive Transdermal Patch

The patch is applied to the skin once per week for three weeks, then removed for one week to allow for menstruation. Common side effects include site reaction, detachment, nausea, and breast pain. Backup or emergency contraception is needed if the patch is removed for more than 24 hours.


Contraceptive Vaginal Ring

The ring is inserted in the vagina for three weeks, then removed for one week to allow for menstruation. Backup or emergency contraception is needed if the ring is removed for more than 3 hours.


Prescribing Considerations

Side effects associated with high estrogen levels include increased risk of venous thromboembolism, nausea, bloating, headaches, and breast pain. At lower estrogen levels, there is an increased risk of breakthrough bleeding. Progesterone has minimal, if any, side effects. 

When prescribing estrogen-containing contraception, consider the following contraindications: 

    • Smokers over age 35
    • Personal history of venous or arterial thrombosis, including myocardial infarction, cerebral vascular accident and venous thromboembolism
    • Migraine with focal neurological symptoms “aura”
    • Hypertension, even if controlled with medication
    • Diabetes with vascular complications
    • Coronary artery disease
    • Liver disease
    • Known pregnancy

Consider drug interactions with the following medications:

    • Some seizure medications
    • Some HIV HAART medications
    • St. John’s wort
    • Rifampin 

Refer to the CDC U.S. Medical Eligibility Criteria for Contraceptive Use for updated prescribing guidelines. 


Emergency medicine providers should be familiar with common misconceptions that patients may have about combined hormonal contraception. Overall, studies have demonstrated: 

  • No association between combination oral contraception or a combination skin patch and weight change.
  • No association between combined oral contraception and mood symptoms.
  •  No known effect on long-term fertility after discontinuing hormonal contraception.
  • A decreased risk of ovarian and endometrial cancer, though there may be a slight increase in the risk of breast and cervical cancer.


Progesterone-Only Contraception 

  • Progesterone-Only Contraception methods are available to patients who have any contraindication to estrogen use or those who do not wish to take estrogen.
  • There are currently four methods available for progesterone-only hormonal contraception: 
      • progestin-only pills 
      • etonogestrel implants
      • depot medroxyprogesterone acetate injections
      • levonorgestrel intrauterine devices (IUDs). 
  • Side effects are often minimal, though bleeding irregularities and amenorrhea are more common than with combined hormonal contraception. 


Progestin-Only Pills (“Mini Pills”)

These pills are commonly prescribed for postpartum women to avoid the increased risk of venous thromboembolism or patients who have other contraindications to estrogen. Backup or emergency contraception is needed if taken greater than 27 hours from the prior pill. However, more recent research shows that some progestin-only formulations may not need to be taken within the strict three-hour window.


Single Rod Etonogestrel (Brand Name: Nexplanon) Implant

Single Rod Etonogestrel is a 4 cm radiopaque implant placed in the upper arm over the  tricep and remains one of the most effective contraceptive methods on the market. Studies demonstrate that the implant maintains an adequate serum etonogestrel concentration to provide contraception for at least five years. Side effects include irregular bleeding and pain at the insertion site. Emergency medicine clinicians must undergo additional training in order to perform the insertion and removal of this device.


Depot Medroxyprogesterone Acetate (Brand Name: Depo-Provera) Injection

DMPA injection is an intramuscular or subcutaneous injection that can be given every three months for continued contraception. DMPA has also been shown to improve fibroid symptoms and suppress endometriosis. Further, it has been shown to decrease the risk of ovarian and endometrial cancer. Data regarding the risk of breast cancer remains inconclusive. Common side effects include irregular bleeding or amenorrhea, temporary changes in bone mineral density, and weight gain.


Levonorgestrel IUDs

Levonorgestrel IUDs are long-acting reversible contraception (LARC) that cause decidualization of the endometrium, leading to glandular atrophy and cervical mucus thickening; this ultimately creates a barrier to sperm penetration and is more than 99% effective at preventing pregnancy. Levonorgestrel IUDs can provide contraception for up to 8 years, depending on the brand. These devices also decrease menstrual blood loss, reduce fibroid-related pain, serve as hormone replacement therapy in menopause, and may be used for endometrial hyperplasia treatment. Side effects include irregular bleeding and amenorrhea, device expulsion, and uterine perforation. Contraindications to IUD placement include uterine anomalies, active or recurrent pelvic infections, certain genital tract cancers, and known pregnancy. 

Non-Hormonal Contraception

Copper IUD

The copper IUD releases copper ions into the uterus, interfering with sperm transport and fertilization. It is more than 99% effective at preventing pregnancy and has no long-term effects on fertility. It provides contraception for up to 12 years. Given that this method is non-hormonal, there are no systemic side effects; however, patients may experience cramping and heavy menstrual bleeding, especially within the first three months. Copper IUDs may also be associated with a clinically insignificant increase in serum copper levels. 


Lactic Acid, Citric Acid, and Potassium Bitartrate (Brand Name: Phexxi) Vaginal Gel

The vaginal gel is applied to the vagina immediately before or up to one hour before intercourse. The gel maintains an acidic vaginal pH to inhibit sperm motility. It is 86% effective at preventing pregnancy with typical use. The most common side effects include vaginal burning or itching, vulvovaginal mycotic infections,  urinary tract infections, and bacterial vaginosis. Male partners may also experience genital burning or itching.

Emergency Contraception

Emergency medicine providers should offer all reproductive-aged female patients emergency contraception after unprotected or under-protected intercourse. Currently, there are two available emergency contraception pills that both function by interfering with ovulation: levonorgestrel pills (brand name: Plan B One-Step) and ulipristal pills (brand name: Ella). There are no known contraindications for either pill. Patients may experience nausea, vomiting, and irregular bleeding. Repeated use is safe, though long-term contraceptive methods should be encouraged. 


Ulipristal (Ella)

Ulipristal disrupts ovulation even after the LH surge has begun; thus, it is more efficacious than levonorgestrel, which is ineffective after the start of the LH surge. Ulipristal requires a prescription and may be taken within 120 hours of intercourse. Ulipristal is effective for women with a BMI up to 35 kg/m2. 


Levonorgestrel pills (brand name: Plan B One-Step)

Levonorgestrel is available over-the-counter and should be taken within 72 hours of intercourse. Levonorgestrel may be ineffective for women with a BMI of 26 kg/m2 or greater.


Copper and Levonorgestrel IUD

The copper IUD or levonorgestrel 52 mg IUDs (e.g., Mirena or Liletta) can also be inserted within 120 hours of intercourse for highly effective emergency contraception. IUD placement is not typically within the emergency medicine scope of practice, though there may be future training opportunities to have this procedure performed in the emergency department to increase patient access to effective long-term contraception and emergency contraception methods.

Promoting Reproductive Health in the ED

In the post Roe v. Wade era in the United States, reproductive-aged patients face unprecedented closures of women’s healthcare clinics and increasingly restrictive access to preferred contraception methods. The emergency medicine setting serves as an opportunity to initiate contraception for high-risk reproductive-aged patients, as well as to connect these patients with outpatient gynecology services for continued reproductive healthcare. Emergency medicine providers should be familiar and comfortable with prescribing both long-term and emergency contraception in the ED, ultimately reducing the burden of unintended pregnancy and its subsequent disparities on vulnerable patient populations.



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