Emergency Contraceptive Pills: Effectiveness and Usage

Regarding emergency contraception?

Hello, I recently had unprotected sexual intercourse and have some concerns.
My girlfriend is currently 20 years old and has a menstrual cycle of about 23 days.
Her last period started on April 9 and ended on April 14.
On April 15, thinking her period had just ended, we had unprotected sex.
Although there was no direct ejaculation inside, I ejaculated immediately after withdrawal.
The next day, on April 16 in the afternoon, I bought an ovulation test kit and surprisingly, the test line was quite dark (about 18 hours after intercourse).
That evening (about 24 hours after intercourse), I went to a nearby clinic, and the doctor prescribed emergency contraception called Norethin, with instructions to take one pill in the morning and one in the evening for a total of 10 pills.
However, I couldn't find any information about this medication when I got home, and the doctor did not explain it clearly.
Is this medication effective for contraception? Is it a progestin or estrogen? How should it be taken correctly? My girlfriend has taken it for two days without any side effects, but why did she test positive for ovulation right after her period ended? Is using an ovulation test kit a suitable method for contraception? Considering her situation, when would be the safest time to engage in sexual intercourse? Thank you, doctor!

JCH, 20~29 year old female. Ask Date: 2017/04/18

Dr. Huang Jianzhong reply Obstetrics and Gynecology

Your girlfriend is currently 20 years old, with a menstrual cycle of approximately 23 days.
She started her period on April 9 and finished on April 14.
On April 15, she thought her period was over and engaged in unprotected intercourse.
Although there was no direct ejaculation inside, ejaculation occurred immediately after withdrawal.
The next day, on April 16 in the afternoon, she bought an ovulation test kit, and the test line was quite dark (about 18 hours after intercourse).
In the evening (about 24 hours after intercourse), she visited a nearby clinic, and the doctor prescribed emergency contraception, named Norethin, with a total of 10 pills, instructing her to take one in the morning and one in the evening.
However, after returning home, she could not find information about this medication, and the doctor did not explain it clearly.
1.
Is this medication effective for contraception? Is it progestin or estrogen?
Answer: It is progestin and can effectively prevent pregnancy.
2.
How should this medication be taken correctly?
Answer: Take one pill in the morning and one in the evening.
3.
Why was ovulation detected right after her period ended?
Answer: This is unusual.
4.
Is using an ovulation test kit for contraception reliable?
Answer: How accurate is the ovulation test kit?
5.
If using the safe period along with condoms, when would be the safest time for intercourse given your girlfriend's situation?
Answer: As long as the condom is used properly and does not leak, any time for intercourse is safe.

Reply Date: 2017/04/18

More Info

Emergency contraceptive pills (ECPs) are a crucial option for preventing unintended pregnancies after unprotected intercourse or contraceptive failure. In your case, your girlfriend has taken a medication called Norethin, which is a form of emergency contraception. Let's break down your questions regarding its effectiveness, usage, and related concerns.

Effectiveness of Norethin
Norethin is a brand name for a medication that contains norethisterone, a synthetic progestin. While it is primarily used for various menstrual disorders, it can also be used as an emergency contraceptive. However, it is important to note that the most commonly recommended emergency contraceptive pills are those containing levonorgestrel (Plan B) or ulipristal acetate (Ella). Norethisterone is not as widely recognized for this purpose, and its effectiveness as an emergency contraceptive may not be as well-studied.

Mechanism of Action
Norethisterone works primarily by preventing ovulation. If taken before ovulation, it can inhibit or delay the release of an egg from the ovary. If ovulation has already occurred, it may alter the uterine lining, making it less suitable for implantation. However, it does not terminate an existing pregnancy.

Correct Usage
The typical regimen for emergency contraceptive pills involves taking the medication as soon as possible after unprotected intercourse. In your case, the doctor prescribed two pills to be taken 12 hours apart. It is crucial to follow this schedule closely for optimal effectiveness. If your girlfriend has taken the pills as directed and has not experienced any adverse effects, that is a positive sign.

Timing of Ovulation
Regarding your concern about ovulation, it is important to understand that menstrual cycles can vary significantly among individuals. A 23-day cycle is relatively short, and ovulation typically occurs around the midpoint of the cycle. In your girlfriend's case, if her last period ended on April 14 and she had unprotected intercourse on April 15, she could be approaching her ovulation window. The ovulation test showing a positive result indicates that she may be close to ovulating, which is why timing is crucial when considering emergency contraception.

Safety Period and Contraceptive Methods
Using the calendar method (tracking safe and unsafe days) can be tricky, especially with shorter cycles. The "safe period" is generally calculated by subtracting 14 days from the length of the cycle to estimate the ovulation day. For a 23-day cycle, ovulation might occur around day 9, making days 5 to 14 potentially risky for unprotected intercourse. Therefore, using condoms during this time is advisable.

Conclusion
In summary, while Norethin can be used as an emergency contraceptive, it may not be the most effective option available. It is essential to follow the prescribed dosage and timing closely. If your girlfriend experiences any unusual symptoms or if her period is delayed beyond a week, it would be wise to take a pregnancy test or consult a healthcare provider for further guidance. For future sexual encounters, consider using reliable contraceptive methods consistently to avoid the stress of unintended pregnancies. Always consult with a healthcare professional for personalized advice tailored to your specific situation.

Similar Q&A

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.

Emergency Contraception: Effectiveness and What to Expect After Use

My period started on November 1 and ended completely on November 12. On the night of the 12th, I had sexual intercourse and accidentally ejaculated inside. That night, I went to the pharmacy and bought Plan B, which contains only one tablet of 1.5 mg. Is it effective? Do I need t...

Dr. Zhang Kunmin reply Obstetrics and Gynecology
Hello, There are mainly two types of emergency contraceptive pills. The first category includes medications such as Postinor, Postinor-2, and Postinor-3, each containing 0.75 mg of levonorgestrel in two tablets. The recommended usage is to take one tablet within 72 hours after ...

Emergency Contraceptive Pills: Effectiveness and Side Effects Explained

Using a condom throughout the entire intercourse, I did not notice that the condom broke until withdrawal, at which point I realized there was ejaculation inside. Within half an hour, I purchased and took the emergency contraceptive pill. Is it still effective for preventing preg...

Dr. Cao Guotao reply Obstetrics and Gynecology
Hello, emergency contraceptive pills can sometimes cause abnormal bleeding. It's best to use preventive contraception beforehand. The effectiveness of emergency contraceptive pills is about 95%. Wishing you good health.

Effectiveness of Emergency Contraceptive Pills Taken After 72 Hours

The efficacy of emergency contraceptive pills (ECPs) taken within three days after unprotected intercourse is approximately 75-89%. If taken within 72 hours, the effectiveness is highest, but it decreases over time. After three days, the effectiveness drops significantly, and ECP...

Dr. Zhang Kunmin reply Obstetrics and Gynecology
Hello, the effectiveness of emergency contraceptive pills taken within three days is approximately 97%. The effectiveness decreases over time, with studies in Canada showing around 90% effectiveness when taken between 3 to 5 days. There is currently no data on effectiveness beyon...