One-dose emergency contraception pills like postinor 2 prevent pregnancy about 50-100% of the time. Postinor-2 has an 85% chance of preventing pregnancy. If taken within 24 hours, there is a 95% chance of preventing pregnancy. If taken after 48-72 hours, there is a 58% chance. It is not known whether it is effective if taken more than 72 hours after unprotected intercourse.
Can Postinor 2 Fail?
Some reasons why postinor 2 pills can fail include ovulation timing, BMI and drug interactions. Most of the time postinor 2 works, when it’s taken within the recommended window following unprotected sex.
You started ovulating before you took the Postinor 2
Emergency birth control is all about timing. It’s recommended that you take the pill as soon as you can—if you wait too long, you might miss the window during which the pill can be effective. If you take it right after sex, it can prevent you from ovulating if you haven’t started already. If you have sex on at the time you ovulate or after you ovulate, your emergency contraception pill won’t be effective. If you have unprotected sex again after you take the pill in the same cycle, it could also fail.
If you have added too much Weight
Healthcare providers use the Body Mass Index (BMI) scale to group people into generic categories based on height and weight. Current studies show that emergency contraceptive pills are less effective for people who have a BMI of 30 or higher. People who have a BMI of 30 or higher who take emergency contraception have pregnancy rates that are 2 to 4 times higher than those with a BMI of 25 or less.
Antiprogesterone emergency contraceptive pills offer better prevention of pregnancy than postinor 2 for those with a BMI of 30 and higher than progestin emergency contraceptive pills, and a copper IUD may be the most effective method of emergency birth control for those with a BMI of 30 or over. Though the postinor 2 pill working has lower efficacy rates for people with higher BMIs, it still prevents pregnancies in this group. It’s better to take it than not take it, in order to prevent pregnancy. ALSO READ: Nigerian Foods and Beverages to Avoid During Pregnancy
Taking postinor 2 with other drugs
Drugs or herbal products can both cause postinor 2 or postpill to be less effective. Take note, these drugs and herbs should not be taken with emergency contraception pills:
- Barbiturates
- Bosentan
- Carbamazepine
- Felbamate
- Griseofulvin (Fucin)
- Oxcarbazepine
- Phenytoin
- Rifampin
- John’s wort
- Topiramate
Be sure to double check the emergency contraceptive package information insert for more detailed information. Hormonal birth control can also cause interactions with the antiprogestin emergency contraceptive pill. We’ll talk more about delayed use, below.
Fake drugs
A major factor that contribute to contraceptive failure especially in developing countries is the proliferation of fake drugs. In a major review of the problem, the World Health Organization (WHO) said that bogus drugs are a growing threat as increased pharmaceutical trade, including Internet sales, open the door to sometimes toxic products. According to the report, one in 10 drugs sold in developing countries is fake or substandard. Fake postinor 2 pills could contain incorrect doses, wrong ingredients or no active ingredients at all. At the same time, a worrying number of authorized medicines fail to meet quality standards because of improper storage and other issues. Always ensure you get your postinor pills from a registered pharmacy outlet. ALSO SEE: Can I Take Postinor 2 Twice In A Week?