Breastfeeding your child already comes with millions of questions, so it’s no surprise that taking any type of medication during this bonding period can feel so stressful—especially something that’s as time-sensitive as emergency contraception (EC) or the morning-after pill. If you’re here to figure out if taking the morning-after pill while breastfeeding is safe, you’re in the right place.
Many nursing parents are concerned about how medications might affect their milk, their baby, or their milk supply. We’re here to tell you that you don’t need to choose between protecting yourself from an unplanned pregnancy and continuing to breastfeed your little one.
In this guide, we’ll explain what the research actually says about emergency contraception and nursing, what you can expect, and how to make a confident, informed decision without all that unnecessary anxiety and stress.
Can You Take the Morning After Pill While Breastfeeding?
If you’re wondering, “Can I take Plan B or Morning After Pill® while breastfeeding?”—the short answer is yes, you absolutely can—and there’s some research to give you some peace of mind.
Plan B, Morning After Pill®, and generic equivalents contain the active ingredient levonorgestrel—a synthetic form of progesterone that’s been used in contraception for several decades and is considered very safe. Researchers have closely studied how this synthetic hormone behaves in the body, including the amount that enters breast milk.
Here’s what they’ve discovered:
- Only tiny amounts of levonorgestrel pass into breast milk.
- The amount of the EC ingested by the infant is extremely low.
- There are no negative effects on infant growth, development, or overall health.
- Breastfeeding does not need to be paused or altered when taking the morning-after pill.
Simply put, taking the morning-after pill while breastfeeding does not expose your baby to harmful hormone levels. This is why clinical guidelines from organizations such as LactMed and the World Health Organization support the use of levonorgestrel as a safe contraception while breastfeeding.
It’s also important to note that levonorgestrel is often used in combination with other breastfeeding-compatible birth control methods, like the mini-pill and hormonal IUDs. So if you’ve ever been told those medications are safe to use while nursing, it makes total sense that Plan B, Morning After Pill®, and other EC options would fall into that same category.
Learn more about how emergency contraception works while breastfeeding.
Does Morning After Pill® or Plan B Affect Milk Supply?
Understandably, for many nursing parents, milk supply feels like a fragile, precious thing—especially in the early postpartum period. So it’s natural to worry about whether Morning After Pill® or other Plan B options affect your milk supply.
Based on the research available, there’s no evidence that the morning-after pill reduces milk production. Studies also show that only small amounts of levonorgestrel pass into breast milk—levels so low that they’re not expected to affect milk supply or infant health.
Levonorgestrel is a progestin-only hormone, and progestins are generally considered compatible with breastfeeding. Unlike estrogen, which can mess with milk production in some people, progestin-only methods have not been shown to impact supply significantly.
In practice, the morning-after pill is typically taken at least four weeks after delivery, when breastfeeding is already well established. By that point, milk production is far less sensitive to short-term hormonal fluctuations, further reducing the risk of supply disruption.
But, with that being said, bodies are very complex. Some nursing parents report very mild, temporary changes—like feeling slightly less full for a day or two. Fortunately, these hormonal fluctuations are short-lived and not clinically meaningful. Stress, hydration, sleep deprivation, and feeding frequency are much more likely to affect your milk supply than a single dose of EC.
If you notice any changes after taking Morning After Pill®, know that they usually resolve pretty quickly without requiring any intervention. Continue to nurse on demand to keep things on track.
How Emergency Contraception Works for Nursing Parents
It’s easy to assume that postpartum bodies respond differently to medication. However, when it comes to emergency contraception, the mechanism doesn’t change just because you’re breastfeeding.
Levonorgestrel-based pills work by delaying ovulation. If you haven’t ovulated yet, delaying it with the morning-after pill can prevent pregnancy from happening. That’s it.
But here are some of the key things that may confuse people:
- The morning-after pill does not terminate a pregnancy.
- It does not interfere with implantation (when a fertilized egg burrows into the uterine lining, marking the start of pregnancy).
- It does not change the composition of breast milk.
- It does not affect infant hormone levels.
For nursing parents, this means that the medication does its job without interfering with breastfeeding or exposing your precious baby to anything harmful. Levonorgestrel doesn’t build up in milk, and it clears from your system naturally over time.
If you’re still in the early stages of postpartum and haven’t had your first period yet, it’s also important to remember that ovulation can happen before menstruation returns. That’s why emergency contraception may still be necessary, even if your cycle hasn’t resumed yet.
Visit our Learn & Share blog for more postpartum and reproductive health guidance.
When Should You Take EC While Breastfeeding?
Timing is one of the biggest factors in how effective the morning-after pill is—regardless of whether you’re breastfeeding or not.
Levonorgestrel works best when it’s taken as soon as possible after unprotected sex. It’s most effective in the first 24 hours, but can still protect for up to 72 hours.
When it comes to breastfeeding logistics, the guidance is refreshingly simple:
- You can take Plan B, Morning After Pill®, and generic options at any time.
- You can continue breastfeeding right away.
- There is no need to wait, pump, or discard breast milk.
- In the first four weeks after delivery, emergency contraception is typically not needed, as ovulation in breastfeeding parents usually does not occur before this point.
Now, some parents choose to take emergency contraception immediately after nursing simply for peace of mind—but know that it isn’t medically necessary. The amount of levonorgestrel in your breast milk is minimal, regardless of when you take it.
If you experience nausea, vomiting, fatigue, dizziness, or headaches—all common side effects—you may want extra hydration and rest, but know that these symptoms don’t impact breastfeeding safety.
Safe Ongoing Contraception Options for Breastfeeding Parents
Please note that while emergency contraception is excellent and should be part of your reproductive toolkit for “whoopsies,” it’s not meant to be a regular form of birth control. If you find yourself frequently panicking about getting pregnant again, it might be time to explore other forms of safe contraception while breastfeeding.
The good news is that nursing parents have plenty of options to consider.
Progestin-Only Pills (Mini-Pill)
The mini-pill contains only progestin and is often recommended during breastfeeding. It won’t interfere with milk production and is safe for infants when taken consistently at the same time each day.
IUDs (Hormonal and Copper)
IUDs are among the most effective forms of contraception out there. Hormonal IUDs release a small amount of progestin, while copper IUDs contain no hormones at all. Both are considered safe during breastfeeding and can last for several years.
Condoms and Other Barrier Methods
Condoms, diaphragms, and cervical caps offer hormone-free pregnancy prevention. They can be used alone or in combination with other birth control methods for added protection.
You might notice that combination birth control pills are missing from this list. Combination birth control pills contain estrogen, which can interfere with milk production—especially in the early postpartum period when supply is still being established. Because of this potential risk, many providers recommend progestin-only or non-hormonal methods for breastfeeding parents until nursing is well established.
Why Clear Guidance Matters for New Parents
The postpartum period is emotionally intense for many parents. You’re adjusting to life with a new baby, navigating physical recovery, and making decisions that feel high-stakes—often on very little sleep.
In moments like these, clear, accurate information about emergency contraception and breastfeeding matters more than ever.
Having reliable guidance on levonorgestrel and breastfeeding can:
- Reduce unnecessary fear and guilt.
- Help you act quickly when timing is critical.
- Support informed, confident decision-making.
- Build trust in accessible reproductive healthcare from resources like Cadence OTC.
When parents don’t have to second-guess their choices, they’re better able to focus on their own well-being and their baby’s health.
FAQs: Breastfeeding and the Morning After Pill
Here are some frequently asked questions about taking the morning-after pill while breastfeeding:
Is levonorgestrel safe while breastfeeding?
Yes. Levonorgestrel is safe to take while breastfeeding your little one. Research shows only minimal transfer of the hormone into breast milk and no known harm to infant growth and development.
Do I need to pump and dump?
Nope. There is no medical reason to pump and discard breast milk after taking Morning After Pill® or other Plan B options.
Can I get pregnant while breastfeeding?
Yes. Breastfeeding is not a reliable form of birth control unless strict lactational amenorrhea criteria are met. Ovulation can occur before your period returns. Ovulation can occur before your period returns, typically beginning around four weeks after delivery.
Does Morning After Pill® or other Plan B options affect my baby?
There is no evidence that Morning After Pill®, Plan B, and generics affect infant health, development, or behavior when taken while breastfeeding.
Conclusion
Levonorgestrel-based options like Morning After Pill®, Plan B, and other EC options are widely regarded as safe and compatible with breastfeeding. Knowing what’s evidence-based (and what’s not) makes it easier to act confidently when it matters most.
Learn more about safe, effective emergency contraception with Cadence OTC.
