Does Evening Primrose Oil Induce Labor?

Are you wondering if primrose oil will put you into labor? I get asked this question a lot (along with what else might put you into labor) and I’m excited to dive into the studies, show you what I learned so you can either decide to drop it, or talk with your provider about it.

Before we get going, the #1 thing you need to be monitoring is baby’s movements.

The bad news: SO many providers educate about kick counts wrong.

The good news: I can give you the RIGHT way to do them here based on you, and your baby — which is what is most important.

Remember baby’s movement is always a comparison against themselves — how are they moving compared to how they usually move? If your provider has said 10 movements in 2 hours, that is WRONG — download the cheat sheet above!

Caution: Advice Ahead

This (or any article on The Pregnancy Nurse) should be taken as medical advice, this purely educational. Please talk with your provider about your specific needs and circumstances.

So, I’m just here to show you what the studies show. I will not be linking to Primrose oil or talking about how to get any because it is SO important to talk with your provider about what your plans are.

If you read this, and decide that primrose is right for you, you should be discussing it at your next checkup. You should NOT be “hiding” this from your provider. They need the full picture of:

• How you’re feeling
• How baby is doing
• What you’re doing

From what I’m reading this isn’t something that should be used prior to 37 weeks at all in pregnancy. If you’re earlier than that just click the back button, or find another article that interests you — this article isn’t for you!

Ok, with that — let’s get into it!

What is Evening Primrose Oil (EPO)?

It is made from the seeds of the evening primrose flowers, found in North America. People traditionally used it to treat conditions including bruises, hemorrhoids, and sore throats.  It contains linolenic acid, gamma-linolenic acid, and vitamin E.

Honestly, in looking at it this is 100% not something that you should be playing around with, without talking to your provider. It looks like it can have other effects that could be really problematic if you had specific conditions including mental or clotting disorders — so PLEASE, AGAIN — talk with your provider.

You can find it with supplements, it’s usually offered as a gel cap. Some people take it for other things like acne, cramps or hot flashes.

What does EPO do?

The thought is that the linoleic acid produces a prostaglandin response in the body. That would be similar to when we use Cytotec (although the results don’t seem to be as immediate).

So, similarly to Cytotec we’re hoping that it will soften the cervix.

The studies measured this cervical softening using the bishop’s score. That’s just a numbers-based rubric that we use to easily say how “favorable” the cervix is to going into labor.

Example: If your cervix is closed, thick and high up in your pelvis it is unlikely to go into labor quickly (doesn’t mean it WON’T — we’re just talking about likelihood) — as compared to a cervix that is a bit open (1-4 cm), soft and baby has moved into your birth canal a bit. That cervix is more likely to go into labor easier. I talk about it in this post on cervical ripening.

Although, they don’t seem to have a total grasp on exactly what the primrose oil is doing.

I will say that a lot of pregnancy is being given options and deciding what works best for you — in consultation with your doctor.

I know that I always felt sort of weird talking to my doctor about things that seemed a bit more “out there” — or frankly, even things that seemed mildly embarrassing, like bloating, or pain in my legs when I worked.

When I learned to communicate better with the principles in here I realized that my provider really does want to help me, but really can’t if I don’t get him/her a full picture of what’s going on.

If you’d like to be able to communicate better with your provider, feel more free to talk to them about what’s really going on, and then get more information to more easily make choices on your own I think this class will be so helpful.

How is it taken?

In the studies they had people taking it oral (by mouth) and also vaginally. In general vaginal showed increase bishop’s score vs oral — although not across the board.

There is a study that showed that oral use wasn’t effective in decreasing pregnancy time.

Don’t worry — I’m going to have a summary of all the studies I read, so keep reading.

Dosing?

Dosing seemed to be somewhat all over the place, but I mostly saw 1,000 mg dosing.

Let me quickly remind you that all supplements can put basically whatever they want on the labeling of their supplement. Meaning, you could get way more than 1,000 mg or way less (or frankly, something entirely different). I always recommend using a vitamin that has 3rd party testing. I tend to get mine at Costco because they have stronger requirements and I’m there all the time. Just a note on that. This is ALSO true of prenatal vitamins.

The start date among the trials varied quite a bit too. Some started daily at 38 weeks, some had a one-time dose, and some for 10 days. There wasn’t really a consensus on when/how long was best.

What do the studies show?

The meta analysis (meaning it looked at several studies and pulled out some main themes between them) showed a decreased the time interval between primrose administration and childbirth.

This means that people who took the primrose oil had their babies sooner than those who didn’t take it (based on the same due dates). I couldn’t find exactly how much sooner they had them…. the charts were confusing and I didn’t see any minutes listed…. and that was the only study I could find that really concluded this.

Across the board it didn’t seem to decrease active labor time (meaning you weren’t laboring for a shorter period of time)

Some did show a decrease in cesareans.

Some also showed an increase in 5-minute APGARS (although no change with 1-minute APGARS). For me, this maybe means baby like struggled less during labor — although I ultimately have no idea. It is good news though, if babies are doing better at 5 minutes, that’s a good thing (babies that have a lower 5-minute APGAR are more likely to need to go to the NICU to transition to an air-breathing world).

The APGAR is another rubric we use to easily communicate to each other how baby transitioned into life after birth — it takes into account how vigorous they are, their color, and more.

On my first baby when I heard rumors of things like this, I mostly just wondered if the item would help me contract. It took some time, and some education, to realize that it was more about the safety of both myself and my baby with the item rather than it just sparking contractions. This is honestly why most don’t recommend midwives brew — because it can have bad effects for both and baby (and likely won’t kick you into labor).

I love that this helps you know what types of questions you should be asking about interventions like cesareans, inductions, or even medications to know if they’re what you (or for your baby) really want.

We aren’t taught important stuff like this in high school, which is why I recommend taking class during your pregnancy. Luckily, that one takes a lot longer than 4 years (more like under 3 hours) and doesn’t include any algebra. Thank goodness!

Risks of Primrose Oil in Pregnancy

Some of the studies did show some risks or drawbacks. These weren’t large numbers of people who had these problems, but enough that they felt it was worth noting.

• Increased chance of meconium staining (where baby poops inside the womb – often shows baby is in distress)
• Some showed nausea, vomiting, diarrhea, prolonged rupture of membranes and arrest of descent.
• It may increase your risk of bleeding if you’re taking clotting/platelet medications.
• I’ve also read you shouldn’t use it if you have any schizophrenia issues.

Ultimately, the risks seem less than that of castor oil — as far as I can tell.

And, of course — as supplements aren’t FDA tested in the US we’re never sure how much is actually in the capsule.

Ultimately, these risks made many studies and professional organizations not recommend primrose oil because they don’t see adequate benefits, but do see a lot of risks (especially if you were doing it at home without baby being monitored).

Want to know more ways to put yourself into labor — check out these posts:

• When Should I Start Drinking Raspberry Leaf Tea?
• Can Curb Walking Induce Labor?
• What is Stripping Membranes? (Membrane Sweep)
• When to start Eating Dates During Pregnancy?
• Can a Hot Bath Induce Labor at 39 Weeks?

Studies Summarized

I pulled out four studies I found and summarized their findings here:

1️⃣This meta analysis showed using EPO in term and post-term pregnant women was clinically effective in improving their Bishop score. This showed both oral and vaginal had this effect. It also increased 5-minute apgar scores.

2️⃣ This one showed there isn’t enough evidence that it does cause cervical ripening.

3️⃣ This study studied it in comparison to Cytotec and It showed that it DID cause cervical ripening and there were less cesareans compared to the Cytotec group (frankly super promising — I hope to see more studies about it).

4️⃣ This one from AJOG showed acupressure, primrose oil and castor oil to be the least effective in cervical ripening.

On a NON-pregnancy front — one other thing I saw studied was how primrose oil might be used to help open the cervix in the days before a gynecological procedure like an IUD insertion or maybe a uterine biopsy. I know those can be really painful, so if we could prep our bodies in advance, that would be amazing. I really think we should be looking into this more, not stifling it!

Now, if you read all these studies and decide that primrose is right for you, you discuss it with your provider and they’re against the idea you can always say “I am planning to take primrose oil — is there anything I should be watching for?” Their job is NOT whether you can take it or not, their job is to explain the risks and what to watch for. I will say most providers (including myself) are going to be against this because there are risks to starting labor on your own at home. Just FYI.

When I was pregnant with my first I really thought my doctor told me what I would/would not do — but as I learned more I realized that I was always in the driver’s seat of my delivery and I got to make the choices.

In Summary

Honestly, none of the evidence was compelling enough to make me think this was a viable way to do something at home. It seems fairly similar to Cytotec in how it can soften the cervix. It also seemed to have very few drawbacks.

I was impressed by the meta analysis that showed a decrease in the amount of time people were pregnant (although, still not sure how much time it shaved off of being pregnant) — and if I was desperate to start my labor at home I might consider it as one of the better options.

Reminder: If you really want to go into labor, talk with your provider about a hospital induction — see which ultimately really seems best for you.

I think if I were to do it, I’d plan to take it vaginally (overall it seems the most effective) which — frankly — doesn’t sound fun as a 9 month pregnant woman. Also, because that area has so much more blood flow during pregnancy I’m always mildly concerned I’ll have a bad reaction to something down there. No thanks.

However, if you’re really wanting to be done being pregnant, it isn’t a crazy think to discuss with your provider. There are clearly a lot of studies on it, and people are looking into it. But, AJOG doesn’t seem to recommend it — so you at least know that going in.

It may have some promise, but again — you want to be SURE that you’re doing it with your provider’s knowledge — and knowing what to watch for as it progresses (or goes nowhere).

And, like I said above — you shouldn’t feel like ANY question is off-limits with your provider. Learning to communicate with them early and often throughout your pregnancy is one of the most important things you can do.

And, remember that YOU are always in the driver’s seat of your birth. You make the choices, you make the calls and they’re just there to consult and assist you as you progress on this journey.

If you wish you…

• felt more comfortable talking with your provider
• wish you knew better questions to ask
• or just wish you understood pregnancy/labor better

I’d recommend jumping into this. In just a few hours we can have you asking questions & laboring like a pro!

Want to do a vibe check before diving into the whole thing with me? — check out my free labor pro tips. It’s your first step toward getting in the driver’s seat of your birth.

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I also have a YouTube video based on this same topic:

Sources:

Shahinfar S, Abedi P, Jahanfar S, Khajehpoor M, Chashmyazdan M. The effect of evening primrose oil on cervical ripening and birth outcomes: A systematic review and meta-analysis. Heliyon. 2023 Feb 8;9(2):e13414. doi: 10.1016/j.heliyon.2023.e13414. PMID: 36846678; PMCID: PMC9947258.

Kalati M, Kashanian M, Jahdi F, Naseri M, Haghani H, Sheikhansari N. Evening primrose oil and labour, is it effective? A randomised clinical trial. J Obstet Gynaecol. 2018 May;38(4):488-492. doi: 10.1080/01443615.2017.1386165. Epub 2018 Feb 9. PMID: 29426270.

Shahraki AD, Mirhoseini S, Movahedi M, Hajihashemy M, Haghollahi F. Comparative Study of the Effect of Vaginal use of Primrose Oil with Misoprostol on Cervical Preparation of Prim Gravid Women: A Double-blind Clinical Trial. Adv Biomed Res. 2023 Mar 28;12:78. doi: 10.4103/abr.abr_30_22. PMID: 37200751; PMCID: PMC10186053.

Outpatient cervical ripening and labor induction with low-dose vaginal misoprostol reduces the interval to delivery: a systematic review and network meta-analysis
Vilchez, Gustavo et al.
American Journal of Obstetrics & Gynecology, Volume 230, Issue 3, S716 – S728.e