Emergency Contraception: Effectiveness and Timing Explained - Obstetrics and Gynecology

Share to:

Emergency contraceptive pill


I'm sorry, Doctor, but I would like to ask you a question! If I have been taking birth control pills for six days and have intercourse on that same day, what are the chances of pregnancy? There is still more than a week until ovulation! Also, is it true that the first pack of pills becomes effective after taking them for a full seven days? Why do some people suggest finishing the entire pack for better effectiveness? Additionally, what are the chances of pregnancy one day and two days after ovulation, considering I have been taking the pills for over two weeks? I'm sorry to trouble you! Also, during the pill-free interval, can I really be assured that I don't need to use protection? (Because isn't it true that it takes a few days for menstruation to start after stopping the pills?) Is it possible to prevent pregnancy during those days without taking the pills?

Mr. Wang, 20~29 year old female. Ask Date: 2016/01/07

Dr. Lin Wenbin reply Obstetrics and Gynecology


The contraceptive effect is better with the second pack; the first pack is less stable.
Even during the seven-day break after the second pack, contraceptive efficacy is still maintained.

Reply Date: 2016/01/07

More Info


Understanding emergency contraception and the effectiveness of regular contraceptive pills is crucial for anyone looking to manage their reproductive health. Let's break down your questions regarding the use of emergency contraception, the timing of ovulation, and the effectiveness of birth control pills.

1. Effectiveness of Birth Control Pills: When taken correctly, most combination oral contraceptives (like Yasmin or other similar pills) are over 99% effective at preventing pregnancy. This means that if you take the pill consistently and correctly for at least seven days, you should have reliable protection against pregnancy. If you have been taking your birth control pills for six days and then have unprotected intercourse, the risk of pregnancy is low, especially if you are more than a week away from ovulation.
2. Timing of Ovulation: Ovulation typically occurs about 14 days before your next expected period, but this can vary depending on your cycle length. If you are more than a week away from ovulation, the likelihood of becoming pregnant from intercourse at that time is significantly reduced.
3. Why Complete a Pack?: Some healthcare providers recommend finishing an entire pack of birth control pills before switching or stopping to ensure maximum effectiveness. This is particularly important if you are transitioning to a new method of contraception or if you are concerned about irregularities in your cycle. Completing the pack helps maintain hormone levels and ensures that ovulation is suppressed.

4. Pregnancy Risk After Ovulation: If you have unprotected intercourse on the day after ovulation or two days after, the risk of pregnancy increases. Sperm can live inside the female reproductive tract for up to five days, so if ovulation occurs shortly after intercourse, there is a chance of fertilization. If you have been on the pill for more than two weeks, your risk of pregnancy remains low, but it is not zero, especially if you miss any doses.

5. During the Pill-Free Interval: Many birth control pills are taken for 21 days followed by a 7-day break. During this break, you will typically have a withdrawal bleed, which mimics a period. It is important to note that if you have been taking your pills correctly before the break, you should still be protected from pregnancy during this time. However, if you miss pills before the break or do not take them as directed, your risk of pregnancy may increase.

6. Emergency Contraception: If you are concerned about the possibility of pregnancy after unprotected intercourse, you may consider using emergency contraception (EC). EC is most effective when taken as soon as possible after unprotected sex, ideally within 72 hours, but some types can be effective up to 5 days later. However, EC should not be used as a regular form of contraception.

In summary, if you have been taking your birth control pills consistently for the required time, the risk of pregnancy after unprotected intercourse is low, especially if you are not close to ovulation. Completing your pill pack is advisable for maintaining contraceptive effectiveness. If you have any concerns about your specific situation or if you experience any irregularities, it is always best to consult with your healthcare provider for personalized advice.

Similar Q&A

Understanding Emergency Contraception: Timing and Effectiveness Explained

If you started your period on March 9th and took your first emergency contraceptive pill at 8 PM, having unprotected intercourse tonight may still provide some level of contraceptive effect, but it is important to note that emergency contraceptive pills are most effective when ta...


Dr. Wu Xianghui reply Obstetrics and Gynecology
Having sexual intercourse during menstruation does not result in pregnancy, but it can increase the risk of vaginal infections and pelvic inflammatory disease in women.

[Read More] Understanding Emergency Contraception: Timing and Effectiveness Explained


Emergency Contraceptive Pills: Timing and Effectiveness Explained

When purchasing emergency contraceptive pills, the pharmacy staff mentioned that taking them on the second day of menstruation is also acceptable. Is the contraceptive effectiveness the same as taking them on the fifth day?


Dr. Zhang Kunmin reply Obstetrics and Gynecology
Hello, the effectiveness of emergency contraceptive pills is not related to the number of days after intercourse, but rather to the timing of ingestion after the event. When taken within 72 hours after intercourse, the effectiveness is approximately 97%. However, it is not 100%, ...

[Read More] Emergency Contraceptive Pills: Timing and Effectiveness Explained


Effectiveness of Emergency Contraceptive Pills During Fertile Window

Taking emergency contraception (the morning-after pill) within one hour after unprotected intercourse during the fertile window does not reduce its effectiveness. Emergency contraception is designed to prevent pregnancy after unprotected sex, and its efficacy is highest when take...


Dr. Cao Guotao reply Obstetrics and Gynecology
Hello, the effectiveness of emergency contraceptive pills is about 90%. It is best to use preventive measures beforehand. Wishing you good health.

[Read More] Effectiveness of Emergency Contraceptive Pills During Fertile Window


Emergency Contraception: Effectiveness After Unprotected Sex During Ovulation

Hello Doctor: I had unprotected intercourse on November 10, and my last menstrual period was from October 29 to November 2. I took Plan B (levonorgestrel) on the evening of November 12 (within 48 hours). Will having intercourse around the time of ovulation and taking emergency co...


Dr. Lü Lizheng reply Obstetrics and Gynecology
1. Taking emergency contraception can reduce the likelihood of pregnancy by 80%. 2. Taking it twice within 72 hours will not increase its contraceptive effectiveness. 3. If you have previous childbirth experience and wish to pursue long-term contraception, you can have an intraut...

[Read More] Emergency Contraception: Effectiveness After Unprotected Sex During Ovulation


Related FAQ

Emergency Contraceptive Pill

(Obstetrics and Gynecology)

Contraception

(Obstetrics and Gynecology)

Oral Contraceptive Pill

(Obstetrics and Gynecology)

Abortion Pill

(Obstetrics and Gynecology)

Ovulation Medication

(Obstetrics and Gynecology)

Medication To Delay Menstruation

(Obstetrics and Gynecology)

Induced Abortion

(Obstetrics and Gynecology)

Ecp

(Obstetrics and Gynecology)

Vaccination

(Obstetrics and Gynecology)

Pregnancy Date

(Obstetrics and Gynecology)