Evening Primrose Oil Before Labor: Does It Really Work?
As your due date gets closer, chances are someone will offer advice on how to "get labor started."
Maybe it's walking.
Maybe it's eating spicy food.
Maybe it's bouncing on a birth ball.
Or perhaps someone has suggested evening primrose oil.
Some women swear it helped them go into labor. Others say it softened their cervix or shortened their labor. You'll find countless stories online describing positive experiences—but does the research support those claims?
The answer is more complicated than a simple yes or no.
While evening primrose oil has been used for many years as a natural labor preparation method, research hasn't consistently shown that it helps start labor, shorten labor, or improve birth outcomes.
Let's look at what we know.
What Is Evening Primrose Oil?
Evening primrose oil (often shortened to EPO) is a supplement made from the seeds of the evening primrose plant (Oenothera biennis).
It's naturally rich in gamma-linolenic acid (GLA), an omega-6 fatty acid that plays a role in the body's production of certain prostaglandins.
Because prostaglandins help the cervix soften and prepare for labor, researchers have wondered whether evening primrose oil might have a similar effect.
That theory has led many pregnant women to use it during the final weeks of pregnancy.
Why Do Women Take Evening Primrose Oil Before Labor?
Most women who take evening primrose oil aren't trying to induce labor.
Instead, they're hoping to encourage cervical ripening, which refers to the natural process of the cervix becoming softer, thinner, and more flexible before labor begins.
Some women also hope evening primrose oil will:
Reduce the likelihood of induction.
Help labor begin naturally.
Shorten labor.
Reduce the chance of cesarean birth.
Make cervical dilation happen more easily.
These are understandable goals.
The challenge is that good scientific evidence hasn't consistently shown these benefits.
How Is Evening Primrose Oil Taken?
If you've searched online, you've probably noticed there isn't one standard way women use evening primrose oil.
Some take it by mouth.
Others insert the capsules vaginally.
Some do both.
Dosages and timing also vary widely, with recommendations often beginning around 37 or 38 weeks of pregnancy.
This lack of consistency makes research difficult because different studies evaluate different doses, methods, and timing.
It also means there isn't an evidence-based "correct" way to use evening primrose oil before labor.
What Does the Research Say?
This is where things get interesting.
Although evening primrose oil has been used for decades, the research is surprisingly limited.
Some small studies have suggested it may improve cervical readiness before labor, while others have found no meaningful benefit.
Several reviews of the available evidence have concluded that there isn't enough high-quality research to recommend routine use of evening primrose oil for labor preparation.
In other words:
The evidence is mixed.
That doesn't necessarily mean evening primrose oil never helps.
It simply means researchers haven't been able to consistently demonstrate that it works.
Why Isn't There a Clear Answer?
One reason is that labor is incredibly complex.
Many factors influence when labor begins, including:
Your baby's readiness.
Hormonal changes.
Cervical changes.
Your body's own production of prostaglandins.
Whether this is your first birth or a subsequent birth.
Because labor naturally varies so much from one pregnancy to another, it's difficult for researchers to determine whether evening primrose oil truly made a difference.
Many women who take evening primrose oil would have gone into labor around that time anyway.
Is Evening Primrose Oil Safe?
This is another area where we don't have complete answers.
Most studies haven't identified major safety concerns when evening primrose oil is used near term, but the overall quality of evidence is limited.
Some reports have raised concerns about possible associations with prolonged rupture of membranes or certain labor complications, while other studies have not found these issues.
At this time, researchers simply don't have enough high-quality evidence to confidently say that evening primrose oil is either clearly beneficial or completely risk-free.
For that reason, many obstetricians and midwives recommend discussing it with your healthcare provider before using it rather than starting it on your own.
Should You Try Evening Primrose Oil?
There isn't one answer that fits everyone.
Some healthcare providers recommend it.
Others don't.
Many take a neutral approach because the evidence is inconclusive.
Rather than relying on stories from friends or social media, the best approach is to discuss your individual pregnancy, health history, and birth goals with your provider before deciding whether evening primrose oil is appropriate for you.
Oral vs. Vaginal Evening Primrose Oil
One question that comes up often is whether evening primrose oil should be taken by mouth or inserted vaginally.
The truth is that there isn't enough high-quality research to recommend one method over the other.
Some healthcare providers who recommend evening primrose oil suggest taking it orally, while others recommend vaginal use during the last weeks of pregnancy. Many providers don't recommend using it at all because the evidence hasn't consistently shown meaningful benefits.
If you're considering evening primrose oil, it's important to remember that "natural" doesn't automatically mean risk-free. Even natural supplements can have side effects or interact with other medications.
What this means for you: Don't assume that one method is safer or more effective simply because it's popular on social media or in pregnancy forums. Talk with your healthcare provider before using evening primrose oil in any form.
Are There Any Risks?
Most women who take evening primrose oil don't experience serious side effects, but that doesn't mean it's completely without risk.
Possible side effects may include:
Upset stomach
Nausea
Loose stools
Headache
Researchers have also explored whether evening primrose oil could increase the risk of certain labor complications, such as prolonged rupture of membranes or changes in labor progression. So far, the evidence has been inconsistent, and no clear cause-and-effect relationship has been established.
Because we don't yet have enough high-quality research to fully understand its safety or effectiveness, many healthcare providers recommend caution.
What this means for you: The biggest concern isn't that evening primrose oil has been proven dangerous—it's that we simply don't have enough strong evidence to know whether the potential benefits outweigh the unknowns.
What If I've Already Started Taking Evening Primrose Oil?
If you've already started taking evening primrose oil after reading about it online or hearing about it from a friend, don't panic.
There isn't strong evidence that occasional use near the end of pregnancy is harmful.
Instead:
Let your healthcare provider know you've been taking it.
Tell them how much you've been taking and whether you've been using it orally or vaginally.
Follow their recommendations based on your pregnancy and medical history.
Remember, many women use evening primrose oil without complications. The reason healthcare providers are cautious is because the research isn't strong enough to recommend it routinely—not because it's been proven to cause harm.
If Not Evening Primrose Oil, How Can I Prepare for Labor?
This is one of my favorite questions because it shifts the focus from supplements to preparation.
While no supplement has been proven to guarantee an easier labor, there are several evidence-based ways to prepare your body and mind for birth.
Consider focusing on:
Staying active with your healthcare provider's approval.
Eating a balanced, nourishing diet.
Staying well hydrated.
Attending childbirth education classes.
Learning comfort measures for labor.
Practicing breathing and relaxation techniques.
Discussing your birth preferences with your healthcare provider.
Working with a doula for continuous labor support.
These approaches may not "start labor," but they can help you feel more confident and prepared when labor begins.
What this means for you: Instead of searching for a single supplement to prepare your body for labor, think about preparing your whole self—physically, emotionally, and mentally.
Questions to Ask Your Provider
If you're considering evening primrose oil, these questions can help guide the conversation:
Based on my pregnancy, do you recommend evening primrose oil?
Is there any reason I should avoid it?
If I choose to use it, when would you recommend starting?
Do you recommend taking it orally or vaginally?
Are there any warning signs that mean I should stop taking it?
Are there other evidence-based ways to prepare for labor?
Frequently Asked Questions
Can evening primrose oil induce labor?
Current research has not consistently shown that evening primrose oil reliably starts labor. While some women report going into labor after using it, studies haven't demonstrated that it causes labor to begin.
Can evening primrose oil soften the cervix?
Some small studies suggest it may influence cervical ripening, while others have found no meaningful effect. More research is needed before routine use can be recommended.
When do women usually start taking evening primrose oil?
Those who choose to use it often begin around 37 or 38 weeks of pregnancy. However, there is no evidence-based guideline recommending a specific start date, and you should always discuss timing with your healthcare provider.
Is evening primrose oil safe if I'm planning a VBAC?
Because research is limited, women planning a VBAC should discuss any supplements—including evening primrose oil—with the healthcare provider managing their pregnancy. Individual recommendations may vary based on your medical history and birth plan.
Should I use evening primrose oil if my provider doesn't recommend it?
It's generally best to follow the guidance of the healthcare professional who knows your pregnancy best. If you're unsure why they recommend for or against it, ask them to explain their reasoning and discuss any questions or concerns you have.
Key Takeaways
Evening primrose oil is commonly used during the last weeks of pregnancy in hopes of preparing the cervix for labor.
Research has not consistently shown that it shortens labor, induces labor, or improves birth outcomes.
There isn't enough high-quality evidence to recommend routine use.
Oral and vaginal use have both been studied, but neither has been proven superior.
If you're considering evening primrose oil, discuss it with your healthcare provider before starting.
The Bottom Line
Evening primrose oil is one of the most talked-about natural labor preparation methods, but it's also one of the most misunderstood.
Despite its popularity, research hasn't consistently shown that it helps start labor, soften the cervix, or shorten labor. At the same time, the available evidence hasn't clearly shown that it's harmful when used near term.
Because the research remains limited and sometimes conflicting, the best approach is to have an open conversation with your healthcare provider about whether evening primrose oil makes sense for your individual pregnancy.
When it comes to preparing for birth, there isn't a magic supplement that guarantees labor will begin at the right time or unfold exactly as planned. Your body and your baby work together in an incredibly complex process that's influenced by many factors.
Rather than focusing on finding the "perfect" supplement, focus on preparing for labor through education, support, movement, nourishment, and informed decision-making. Those are the things most likely to help you approach birth with confidence.
How Intercessory Birth Can Help
Preparing for birth can feel exciting, overwhelming, and sometimes confusing—especially when you're hearing different advice from friends, family, social media, and healthcare professionals.
At Intercessory Birth, my goal is to help you sort through the noise by providing evidence-based education that's practical, balanced, and easy to understand. Whether you're planning your first birth, preparing for a VBAC, or simply trying to make informed decisions about your pregnancy, I'm here to help you feel confident and supported every step of the way.
Medical Disclaimer
This article is intended for educational purposes only and should not be considered medical advice. It is not a substitute for individualized care from your obstetrician, midwife, family physician, or another qualified healthcare professional. Always consult your healthcare provider before starting, stopping, or changing any medication, vitamin, herbal supplement, or treatment during pregnancy.
References
American College of Obstetricians and Gynecologists. Induction of Labor and patient education resources.
National Center for Complementary and Integrative Health. Herbs at a Glance.
National Institutes of Health Office of Dietary Supplements. Dietary Supplements: What You Need to Know.
MotherToBaby. General pregnancy medication and supplement resources.
Cochrane Pregnancy and Childbirth Group. Reviews on methods of cervical ripening and labor induction.
Society for Maternal-Fetal Medicine. Patient education resources.
