Birth control pill vs. the Depo-Provera shot facts

Picture of a packet of pills and syringe with liquid.
Picture of a packet of pills and syringe with liquid.

How effective are birth control pills vs. shot?

  • Both the pill and the shot are very effective methods of birth control.
  • When combination birth control pills are taken correctly, they are up to 99% effective in preventing pregnancy.
  • Progestin-only pills are about 95% effective.
  • The birth control shot (Depo-Provera) also is about 99% effective in preventing pregnancy (average annual failure rate is about 3%).

Do birth control pills or shots cause weight gain?

Yes, women have reported weight gain while taking oral contraceptives and using the Depo-Provera shot.

Side Effects of Birth Control Pills

Combination birth control pills contain estrogen and progestin, and are about 99% effective in preventing pregnancy if you take them as directed. The mini-pill only contains estrogen, and is up to 95% effective.

Examples of side effects of birth control pills include weight gain, irregular bleeding, mood changes, nausea, and breast tenderness.

What are the differences and similarities between how birth control pills vs. the shot work?

Birth control pills and the birth control Deop-Provera shot are both hormonal methods of birth control. This means that they work by changing hormone levels in your body, preventing pregnancy from occurring. The hormones in birth control pills prevent release of an egg, or ovulation.

Birth control pills

Birth control pills are available as combination pills, containing the hormones estrogen and progestin, or as mini-pills containing progestin only.

  • Both typically come in packs of 28 pills, and you take one pill daily.
  • With combination pills, the last 7 pills in the pack do not contain hormones, and while you are taking these non-hormone pills, your menstrual period occurs.
  • The menstrual period also occurs during the last 7 days of the progestin-only pill packs.
  • Some newer types of birth control pills are taken continuously for a few months without the inactive pills, before a menstrual period occurs.
  • The pill also work to make the cervix (opening to the womb or uterus) and the uterus itself unfavorable for a pregnancy to begin.

Depo-Provera shot

  • The birth control shot is known as Depo-Provera (and the newer low-dose Depo-SubQ Provera 104).
  • The Depo-Provera shot contains the hormone progestin and prevents pregnancy for three months in a row.
  • Like the hormones in birth control pills, the progestin in the shot make the environment in the uterus unfavorable to begin a pregnancy and may stop ovulation.

SLIDESHOW

Choosing Your Birth Control Method See Slideshow

Which side effects of the pill vs. shot are different and similar?

Unique side effects for oral contraceptives

  • Nausea
  • Vomiting
  • Mood changes
  • So called “breakthrough” bleeding or spotting at times other than the menstrual period.
  • The side effects of the pill tend to get better after you have been using it a few months.

Unique side effects of the Depo-Provera injection

Similar side effects of the pill vs. Depo-Provera injection

  • Both methods can cause tenderness or soreness of the breasts.
  • Other side effects of oral contraceptives and the Depo-Provera shot include headaches and mood changes.
  • Both methods can lead to a decreased interest in sex (decreased libido) in some women.

What are the risks of the pill vs. shot?

Both the pill and the shot do not offer any protection against sexually-transmitted diseases (STDs). Missing pills or taking longer than 12 weeks to get another shot increases the chances of becoming pregnant.

Other health risks of oral contraceptives

  • Combination birth control pills have been linked to a small increase in the risk of heart attack. However, this is a very rare event in young women.
  • Birth control pills that contain estrogen increase the risk of blood clots, and some types of pills may increase the risk of stroke. Because of these risks, it is recommended that women over age 35 who smoke cigarettes, hookahs, etc. (tobacco) not use birth control pills.
  • Birth control pills appear to increase the risk of cervical cancer, but decrease the risk of ovarian and endometrial (lining of the uterus) cancer.
  • Data about their effect on breast cancer risk are not clear.
  • Women with migraine headache also appear to have an increased risk of blood clots when taking the pill, particularly women over age 35.

Other health risks of the Depo-Provera shot

QUESTION

Which of the following are methods for contraception? See Answer

What are other birth control options?

There are many different kinds and choices of birth control to prevent from becoming pregnant, for example, hormonal, for methods like birth control pills, and the birth control shot. Other birth control methods include:

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Medically Reviewed on 4/13/2020
References
What are the different types of birth control? NIH. Updated: Jan 31, 2017.
<https://www.nichd.nih.gov/health/topics/contraception/conditioninfo/Pages/types.aspx#LARC>

Learn About Birth Control. Planned Parenthood. 2020.
<https://www.plannedparenthood.org/learn/birth-control>
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