Contraception

Overview

Introduction

The US has one of the highest rates of unintended pregnancy in the developed world. About half of all pregnancies in the US are unintended. Of these, approximately 40% end in abortion.[1] [2]

The abortion rate in the US decreased by 21% between 2010 and 2019. In 2019, there were 11.4 abortions per 1000 women ages 15 to 44 years.[3] Although the overall abortion rate has declined, this is not seen across all population groups, with higher rates of unintended pregnancy and abortion in disadvantaged groups.[2] [4] This disparity suggests there is limited access to contraception for some women and adolescents, and points to the importance of addressing birth control with all patients at risk for unintended pregnancy. To improve women's contraceptive options and their choices of place to access contraception, the World Health Organization recommends self-care interventions (e.g., self-injectable contraception and the over-the-counter availability of oral contraception).[5]

Initial counseling

Contraceptive counseling should be patient-centered and aim to provide accurate information about all methods that the woman is medically eligible for, to help her choose which is best for her.[6] This should include information about the efficacy, risks, and side effects, as well as advantages, disadvantages, and noncontraceptive benefits of all methods that are available to her.[7] [8]

Selecting an appropriate contraceptive method requires a complete medical history, with special focus on ruling out the most common contraindications. Several organizations provide guidance on the safety of different contraceptive methods in relation to health conditions and personal characteristics. These include the World Health Organization Medical Eligibility Criteria for contraceptive use (MEC), the Centers for Disease Control and Prevention (CDC) US Medical Eligibility Criteria (USMEC), the American College of Obstetricians and Gynecologists (ACOG), and the Faculty of Sexual and Reproductive Healthcare Medical Eligibility Criteria (UKMEC) in the UK.[8] [9] [10] Consult the relevant guidance for your area when providing contraception to women.

Initial counseling should include a general discussion about the risks and prevention of STIs.[11] A dual-protection strategy (i.e, condoms plus a second method) should be discussed with users of long-acting reversible contraceptive (LARC) methods because LARCs do not offer protection against STIs. The Contraceptive CHOICE cohort study reported a higher incidence of STIs in users of LARC methods.[12] Additionally, a study in postpartum teenage mothers found that condom use was lower among users of LARC, relative to non-LARC users.[13] These findings suggest a need for accurate and thorough counseling about STI risk and prevention alongside pregnancy prevention. However, it is important that this does not discourage providers from including LARC among methods offered, particularly given their efficacy in preventing pregnancy.

The ACOG recommends that pre-exposure prophylaxis should be discussed with all sexually active adolescent and adult patients for prevention of HIV.[14] See HIV infection (Prevention) .

Patients can be reassured that a cervical cytology test and pelvic exam are not required before starting most contraceptives.[7] [15]

Consider the patient's social context when discussing their contraceptive choices. For example:

A teenager whose parents disapprove of sexual activity may request a method that is easy to conceal
A working mother who travels often may be unable to remember a daily pill
An uninsured patient needs a method she can afford.

Adapt the approach to counseling for adolescents to ensure that information about contraceptive methods is given in a way that is developmentally appropriate and check their understanding. In addition, it is important to address any common misconceptions that adolescents may have concerning the different methods available.[16]

To maximize adherence, honor the patient's preferences, prescribing the particular method each patient chooses, unless a contraindication prevents this. However, it is also important to ensure that patients know their options, with special emphasis on awareness of the highest-efficacy methods. Patients who receive an ample initial supply of their contraceptive are more likely to adhere to treatment.[17]

The CDC's downloadable resources include a comparison of the effectiveness of different contraceptive methods, as well as other tools to use with patients.

CDC: reproductive health - contraception

Efficacy of contraception (defined as rates of unintended pregnancies per 100 women) is split into the following categories when comparing the effectiveness of different contraceptive methods:[18]

0 to 0.9: very effective

1-9: effective

10-19: moderately effective

20+: less effective.

Active military service generally reduces the adherence and effectiveness of contraception (50% to 65% of pregnancies are unintended in this population) and can therefore affect the suitability for some types of contraceptive (e.g., depot medroxyprogesterone acetate and the vaginal ring). Consequently, the ACOG recommends the use of long-acting reversible contraceptives (intrauterine devices or implant) for these women.[19]

Additionally, contraceptive measures should be discussed with women of child-bearing age who are taking potentially teratogenic medications.[20] Female patients should be enrolled in a pregnancy prevention programme, where there is one available, if they are taking sodium valproate.[21] This involves an annual assessment of the need for treatment with sodium valproate and a discussion of the risks of taking the drug during pregnancy. Patients should use a highly effective, user independent form of contraception such as a LARC.[21]

Barrier methods

Barrier methods include:

Diaphragm and cervical cap

Female condom
Male condom
Spermicide (nonoxynol-9).

While barrier methods offer only moderate efficacy for prevention of unintended pregnancy, condoms and spermicide are available without a prescription, and latex/polyurethane condoms protect against HIV and other STIs.[11] Successful use of barrier methods requires consistency and discipline during intercourse. All barrier methods may be used safely during lactation.

Barrier methods: the diaphragm and cervical cap

The estimated pregnancy rate during typical and perfect use of the diaphragm is 17.4% and 16.3%, respectively.[1] The diaphragm and cervical cap must be fitted initially and prescribed by clinicians trained in their use. They must be filled and coated with spermicide and inserted before intercourse. Subsequent episodes of intercourse within 6 hours require vaginal insertion of more spermicide with an applicator. The diaphragm and cervical cap do not prevent HIV transmission. To use a cervical cap, the woman must be able to locate her cervix accurately.

Side effects and disadvantages include:

Skin irritation
Increased risk of bladder infection (diaphragm only)
Possible increase in risk of HIV transmission. There is evidence that frequent use of spermicide (the diaphragm or cap needs to be used with spermicide) does not decrease, and may actually increase, the risk of HIV transmission.[22] [23]

Barrier methods: the female condom

The female condom is 79% to 95% effective for pregnancy prevention (typical to perfect use).[1] It consists of a lubricated polyurethane pouch that is inserted inside the vagina during sex. A new condom must be used each time a couple has intercourse. With proper use, the female condom can prevent transmission of HIV and other STIs.

Side effects and disadvantages include:

Friction/noise during intercourse
Loss of sensation
Inconvenience/interruption of sex
Slippage/breakage (has a higher risk of slippage than the male condom).

Citations

Key Articles

Curtis KM, Nguyen AT, Tepper NK, et al. U.S. selected practice recommendations for contraceptive use, 2024. MMWR Recomm Rep 2024;73(3):1-77.[Abstract][Full Text]
The Faculty of Sexual & Reproductive Healthcare (FSRH) of the Royal College of Obstetricians & Gynaecologists. UK Medical Eligibility Criteria for contraceptive use (UKMEC). Sep 2019 [internet publication].[Full Text]
World Health Organization. Medical Eligibility Criteria for contraceptive use (MEC). Fifth edition. Aug 2015 [internet publication].[Abstract][Full Text]
Nguyen AT, Curtis KM, Tepper NK, et al. U.S. medical eligibility criteria for contraceptive use, 2024. MMWR Recomm Rep 2024;73(4):1-126.[Abstract][Full Text]
Stewart FH, Harper CC, Ellertson CE, et al. Clinical breast and pelvic examination requirements for hormonal contraception: Current practice vs evidence. JAMA. 2001 May 2;285(17):2232-9.[Abstract]
American College of Obstetricians and Gynecologists. Practice bulletin no. 186 summary: long-acting reversible contraception: implants and intrauterine devices. Obstet Gynecol. 2017 Nov;130(5):1173-5.[Abstract]

Other Online Resources

CDC: reproductive health - contraception
WHO: family planning - a global handbook for providers
Reproductive Health Access Project: quick-start algorithm
CDC: when to start using specific contraceptive methods
Reproductive Health Access Project: IUD information
Office on Women's Health: emergency contraception

Referenced Articles

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Diseases