How Do I Know Whether The Morning After Pill Has Worked?

Unprotected sex or contraceptive failure can happen to anyone, and it can quickly lead to anxiety about an unplanned pregnancy. In the UK, thousands of people seek emergency contraception each year after a condom breaks, a pill is missed, or sex occurs without protection. The morning-after pill is designed for exactly these situations. When taken as soon as possible after unprotected sex, emergency contraceptive pills can be highly effective at preventing pregnancy.

However, after taking it, many people start wondering whether it has actually worked. Searching for signs the morning-after pill worked or trying to figure out how to tell if the morning-after pill worked is very common. In this guide, we explain what to expect, the morning-after pill success rate, and when to test after the morning-after pill.

Does the Morning-After Pill Always Work?

Emergency contraceptive pills are highly effective when taken as soon as possible after unprotected sex. They work mainly by delaying ovulation so that the ovaries do not release an egg that sperm could fertilise.

The morning-after pill success rate depends on several factors, including how quickly it is taken and which type you use. When taken correctly, emergency contraception can prevent pregnancy in the vast majority of cases.

In the UK, the two most commonly used emergency contraceptive pills are Levonelle and ellaOne. These medicines work slightly differently and have different time windows for use.

How Levonelle Works

Many people specifically ask about how Levonelle works and how to know Levonelle worked after taking it.

Levonelle contains levonorgestrel, a synthetic hormone similar to progesterone. It works by delaying or preventing ovulation. If ovulation does not occur, there is no egg available for sperm to fertilise.

Levonelle must be taken within 72 hours after unprotected sex. Its effectiveness is highest the sooner it is taken.

Levonelle Effectiveness

Levonelle effectiveness varies depending on how quickly it is taken.

• Up to 99 per cent effective when taken within 24 hours.
• Around 85 per cent effective when taken within 25 to 48 hours.
• Around 58 per cent effective when taken within 49 to 72 hours.

Because of this, our pharmacists usually recommend taking it as soon as possible after unprotected sex.

What Are the Signs the Morning-After Pill Worked?

Many people search for signs the morning-after pill worked, but it is important to understand that the medicine usually works quietly in the body, so there are no immediate physical signs to confirm it has worked. However, some changes can occur after taking emergency contraception.

Changes to Your Next Period

One of the most common morning-after pill results is a change in your menstrual cycle.

Your next period may:

• arrive earlier than expected.
• arrive a few days later than usual.
• be heavier or lighter than normal.

These changes are caused by the hormones in the pill affecting your cycle.

Mild Side Effects

Some people experience temporary side effects after taking the pill. These can include:

• nausea.
• headache.
• tiredness.
• stomach discomfort.
• breast tenderness.

Experiencing these effects does not necessarily mean the pill worked, but they can happen as your body responds to the hormones.

Light Spotting

Some people notice light spotting a few days after taking emergency contraception. This can happen as hormone levels shift in your body.

However, spotting is not a reliable sign that the pill has worked.

When Should You Take a Pregnancy Test After the Morning-After Pill?

Many people wonder when to test after the morning-after pill. Testing too early can lead to inaccurate results.

Pregnancy tests detect a hormone called human chorionic gonadotropin, also known as hCG. This hormone is only produced after a fertilised egg implants in the womb.

Because of this, it takes time for levels to rise high enough for a test to detect them.

When to Test After the Morning-After Pill

In most situations, the best time to test is:

• after your next period is due.
• at least three weeks after unprotected sex if your periods are irregular.

Taking a test too early may give a false negative result.

Many early detection tests claim to work before a missed period. While they may sometimes detect pregnancy earlier, results are generally more reliable once your period is late.

What Can Make the Morning After Pill Less Effective?

Although emergency contraception is very effective, certain factors can reduce its effectiveness.

Vomiting or Severe Diarrhoea

If you vomit within three hours of taking the pill, your body may not have absorbed the medicine properly.

In this situation, speak to our pharmacist, as you may need another dose.

Certain Medicines

Some medicines can reduce how well emergency contraception works. These include:

• St John’s Wort.
• certain antifungal medicines.
• some medicines used to treat HIV.
• medicines that affect the immune system.

Talk to our pharmacists to understand whether these medicines could affect emergency contraception.

Body Weight

Some research suggests that levonorgestrel-based emergency contraception may be less effective for people with a higher body weight or BMI.

If this applies to you, our pharmacists can discuss alternative options that may be more suitable.

What About Other Emergency Contraception Pills, Like the P2 Pill or i-Pill?

Some people also search online for signs the P2 pill worked or wonder how to know the P2 pill worked. Others look for information about i-pill effectiveness and when it becomes clear whether it has worked.

These medicines are common emergency contraception brands in some countries. Like Levonelle, they usually contain levonorgestrel and work in the same way by delaying ovulation.

Because they work using the same hormone, the way to assess whether they worked is also the same.

You cannot immediately confirm that they have worked. Instead, you should wait for your next period or take a pregnancy test at the appropriate time.

Need Emergency Contraception Quickly?

If you are concerned about unprotected sex or contraceptive failure, it is important to act quickly because emergency contraception works best when taken as soon as possible.

At Pharmacy Planet, our GPhC registered pharmacists review a short online consultation to confirm whether treatment is suitable for you. This helps ensure emergency contraception is supplied safely and appropriately.

Once approved, your medication can be dispatched discreetly and quickly to your home, allowing you to access treatment without visiting a clinic or pharmacy in person.

Shop emergency contraception online at Pharmacy Planet with a quick and secure consultation reviewed by our pharmacists.

Frequently Asked Questions (FAQ's)

How long does it take to know if the morning-after pill worked?

There is no immediate way to confirm the morning-after pill results. The most reliable way to tell if the morning-after pill worked is to wait for your next period or take a pregnancy test.

What are the most common signs the morning-after pill worked?

There are no guaranteed signs the morning-after pill worked. However, your next period arriving on time or only slightly delayed is usually the clearest indication that emergency contraception was successful.

How do I know Levonelle worked after taking it?

If your next period arrives as expected, this is usually the best sign of Levonelle effectiveness. If your period is more than a week late, you should take a pregnancy test.

What is the morning-after pill's success rate?

The morning-after pill success rate depends on how quickly it is taken. Levonelle can be up to 99 per cent effective within 24 hours, though effectiveness decreases the longer you wait.

When should I test after the morning-after pill?

If you are unsure about morning-after pill results, you should wait until your next period is due. If your cycle is irregular, test at least three weeks after unprotected sex.

How can I tell if emergency contraception like the i-pill or P2 pill worked?

The only reliable way to know how to tell if emergency contraception worked is to wait for your next period or test later. The same rule applies when checking i-pill effectiveness.