Is Evening Primrose Oil Safe During Pregnancy?

Evening primrose oil is one of the most popular home remedies for getting labor going, and the honest answer on its safety is “not proven either way.” How it’s used changes the picture a great deal: the capsules taken by mouth and the same capsules placed in the vagina have produced quite different results. Almost everything we know also comes from women who were already full term, so it says nothing reassuring about earlier pregnancy.

Why People Use Evening Primrose Oil Near Their Due Date

The oil comes from the seeds of the evening primrose plant and is sold as soft gel capsules. It contains a fatty acid the body may use to make prostaglandins.1PubMed Central. The effect of evening primrose oil on cervical ripening and birth outcomes: A systematic review and meta-analysis Prostaglandins are the body’s main signal for softening and opening the cervix before labor.2PubMed Central. The effect of evening primrose oil on cervical ripening and birth outcomes: A systematic review and meta-analysis So the oil is meant to prepare the cervix rather than directly cause contractions. A ripe cervix doesn’t guarantee labor will start soon. In the last weeks before labor the cervix softens, shortens and starts to open, which is what “ripening” means.

Many midwives have used it. In a national survey of nurse-midwives who used herbal remedies to stimulate labor, 60% used evening primrose oil.3PubMed. A national survey of herbal preparation use by nurse-midwives for labor stimulation. Review of the literature and recommendations for practice It was also the herbal remedy most often taught in nurse-midwifery training programs.4PubMed. A national survey of herbal preparation use by nurse-midwives for labor stimulation. Review of the literature and recommendations for practice

That popularity reflects tradition and experience, not trial proof. Supplements aren’t checked for safety in pregnancy before they reach the shelves. And hospital labor medicines also work through prostaglandins, so a supplement acting the same way isn’t automatically gentle.

Does It Actually Soften the Cervix or Start Labor

Your provider may describe your cervix with a “Bishop score,” a number from an internal exam that rates how soft, thin, open and low it is. Higher means more ready for labor. Each feature gets points: a low total means the cervix is still firm and closed, a high total means it is well prepared. It’s a snapshot of one moment and can differ a little between examiners, so a single number is a rough guide, not a precise measurement.

Studies judge evening primrose oil by whether this score rises more than it does with a dummy pill.5PubMed. The Use of Evening Primrose Oil for Cervical Ripening in Low-Risk Women with Term Pregnancy: A Randomized Double-Blinded Controlled Trial That comparison matters because cervixes keep ripening by themselves in the last weeks. A dummy capsule group shows how much change happens anyway. It’s also why a friend’s story of labor starting after capsules can’t show the oil worked: labor may have been about to start anyway.

Taken by mouth, the oil doesn’t appear to help. Pooling four trials, capsules swallowed by mouth did not improve softening of the cervix compared with no treatment.6PubMed. The effect of evening primrose oil on labor induction and cervical ripening: A systematic review and meta-analysis In low-risk first-time mothers, taking it by mouth from 37 weeks didn’t shorten pregnancy or overall labor length.7PubMed. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women Another trial found no difference in how far along women delivered, or in how often labor needed to be started or sped up with hospital drugs.8PubMed. Evening primrose oil and labour, is it effective? A randomised clinical trial

Used vaginally, the results are more mixed. In one double-blind trial of low-risk full-term women, vaginal capsules raised the cervix readiness score to about 5.8, versus about 5.2 with a dummy capsule.9PubMed. The Use of Evening Primrose Oil for Cervical Ripening in Low-Risk Women with Term Pregnancy: A Randomized Double-Blinded Controlled Trial The gain was real but small, less than one point on the scale. A one-point rise in score doesn’t mean labor will start that day. A broader pooled review found readiness scores about 1.3 points higher, fewer caesareans and a first stage of labor shorter by about an hour and a half.10PubMed. Evening primrose oil for cervical ripening in term pregnancies: a systematic review and meta-analysis But those trials differed so much in method and quality that the reviewers called for better studies before relying on the result.11PubMed. Evening primrose oil for cervical ripening in term pregnancies: a systematic review and meta-analysis The results disagree partly because studies used different doses, routes, start dates and lengths of use, and most trials were small.

What the Research Shows About Your Baby’s Safety

Right after birth, babies get an Apgar score, a quick 0 to 10 check of breathing, heart rate, color, tone and reflexes at 1 and 5 minutes. In one triple-blind trial, babies whose mothers used oral or vaginal capsules had 5-minute scores near 10, the same as those without.12Journal of Nursing and Midwifery Sciences. Comparing the Effects of Oral and Vaginal Evening Primrose Capsules with Concurrent Labor Induction and Exclusive Labor Induction on Bishop Score and Some Labor Outcomes: A Triple-Blind Clinical Trial The share of babies passing their first stool before birth, a possible stress sign, didn’t differ between groups either.13Journal of Nursing and Midwifery Sciences. Comparing the Effects of Oral and Vaginal Evening Primrose Capsules with Concurrent Labor Induction and Exclusive Labor Induction on Bishop Score and Some Labor Outcomes: A Triple-Blind Clinical Trial Another trial found no differences in birth weight, baby’s newborn check scores, or reasons for hospital admission.14PubMed. Evening primrose oil and labour, is it effective? A randomised clinical trial Across pooled trials, birth weight wasn’t affected.15PubMed. Evening primrose oil for cervical ripening in term pregnancies: a systematic review and meta-analysis

That reassurance has limits. Every reviewed study only included women at least 37 weeks pregnant with a healthy baby.16PubMed Central. Systematic Review of Evening Primrose (Oenothera biennis) Preparations for the Facilitation of Parturition There’s no evidence about safety earlier in pregnancy. “No difference found” in a few hundred women only means problems weren’t more common in that group, not that the oil is proven safe. Rare complications need thousands of pregnancies to detect, so small trials can miss them.

Before 37 weeks is a different question. Anything that ripens the cervix could, in theory, matter more before the baby is ready, and some clinical sources list oral use as unsuitable before term for this reason. Don’t start it early to get ahead of your due date.

Possible Risks During Labor When Taken by Mouth

In low-risk first-time mothers, taking it by mouth from 37 weeks may be linked to more cases of waters broken for a long time before birth.17PubMed. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women The same group may have more often needed a hospital drip to strengthen contractions.18PubMed. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women More cases of the baby stopping moving down the birth canal and more vacuum-assisted births were seen too.19PubMed. Oral evening primrose oil: its effect on length of pregnancy and selected intrapartum outcomes in low-risk nulliparous women

In a matched comparison, these trends at a dose of 500 mg three times a day didn’t reach clear statistical proof.20THE JOURNAL OF FAMILY PRACTICE. Do any folk remedies or herbals help induce labor? Even so, a family-medicine evidence review rated it ineffective and possibly unsafe for starting labor.21THE JOURNAL OF FAMILY PRACTICE. Do any folk remedies or herbals help induce labor?

Waters broken for many hours raises the chance of infection for you and baby, and a stalled labor can lead to a drip, vacuum delivery or caesarean. Those are the very interventions many people hope a natural remedy will avoid.

The pattern was seen with oral use, not with vaginal use in the trials. Vaginal trials mostly showed neutral or slightly better labor outcomes, so the two routes shouldn’t be treated as interchangeable. If your midwife suggests it, ask which route she means and why.

Bleeding after birth is the other worry. In one trial, evening primrose oil didn’t change bleeding in the first two hours after birth.22Al-Azhar University Journal of Medical and Virus Researches and Studies. The Effect of Evening Primrose Oil in Cervical Ripening and Induction of Labor But the oil can reduce how well platelets clump to stop bleeding,23Alberta Rheumatology. Evening Primrose Oil and Mayo Clinic notes it might raise the risk of pregnancy complications.24Mayo Clinic. Evening primrose

Who Should Not Take Evening Primrose Oil

Don’t take it if you have a bleeding condition, since it may raise bleeding risk.25Mayo Clinic. Evening primrose It may also increase bruising and bleeding if combined with blood thinners or anti-platelet drugs.26Alberta Rheumatology. Evening Primrose Oil If you take low-dose aspirin in pregnancy, ask before adding it. The advice is to stop taking the oil two weeks before any surgery,27Mayo Clinic. Evening primrose and a scheduled caesarean counts as surgery for this purpose.

It may also raise seizure risk in people with epilepsy or schizophrenia.28Mayo Clinic. Evening primrose This applies especially to people treated with phenothiazine medicines such as chlorpromazine, fluphenazine or prochlorperazine.29Alberta Rheumatology. Evening Primrose Oil Prochlorperazine is sometimes used for severe pregnancy nausea, so mention it if you’ve been prescribed it.

Before trying the oil, give your provider the full picture: every medicine and supplement you take, including aspirin and fish oil; any history of seizures, heavy bleeding or easy bruising; and whether a caesarean or other procedure is planned. Ask whether your pregnancy is low-risk enough for it at all. Most providers would say no in some situations: before 37 weeks, after a previous caesarean or uterine surgery (where ripening needs closer oversight), or with placenta problems, bleeding, or a baby that isn’t head-down.

Doses and How It Is Used

Trials never agreed on one schedule, and more isn’t shown to work better. Your provider’s chosen dose is the one to follow.

For vaginal use, people usually insert a capsule high in the vagina at bedtime. Some oily discharge afterward is expected. Stop if you notice bleeding, fluid leaking or strong pain, and call your provider. Don’t use it vaginally if your waters have broken.

The oil’s makeup depends on how the plant was grown and extracted, so effects may differ between brands.35Examine. Evening Primrose Oil It spoils with air and light and should be kept in a dark, tightly sealed container.36Examine. Evening Primrose Oil Testing of food supplements in general has found widely varying levels of contaminants,37PubMed Central. EU marker polycyclic aromatic hydrocarbons in food supplements: analytical approach and occurrence so choose a brand with independent third-party testing.

Other Natural Labor Remedies and Hospital Options

Red raspberry leaf appears likely safe but didn’t shorten labor or change birth outcomes in a trial of 192 women.38THE JOURNAL OF FAMILY PRACTICE. Do any folk remedies or herbals help induce labor? Black and blue cohosh lack evidence they work and may be unsafe.39THE JOURNAL OF FAMILY PRACTICE. Do any folk remedies or herbals help induce labor? Castor oil caused nausea in every woman who took it, without changing caesarean rates or newborn scores.40THE JOURNAL OF FAMILY PRACTICE. Do any folk remedies or herbals help induce labor? It was nonetheless the remedy nurse-midwives used most, by 93% of those who used herbs.41PubMed. A national survey of herbal preparation use by nurse-midwives for labor stimulation. Review of the literature and recommendations for practice

Hospitals often ripen the cervix with misoprostol, a prostaglandin drug. The one trial comparing vaginal evening primrose oil with misoprostol was in non-pregnant women before gynecological surgery, so it doesn’t tell you how they compare for labor.42PubMed. Comparison of Misoprostol and Evening Primrose Oil on Cervical Preparation Before Gynecological Surgery Evening primrose oil is not a replacement for a medical induction your provider recommends.

During induction, your baby’s heart rate is tracked while ripening drugs work, and doses can be stopped or adjusted if contractions get too strong. Home remedies come with no monitoring at all. Ask your provider when induction would be offered if you go overdue.

Is Evening Primrose Oil Safe While Breastfeeding

Nursing mothers who took it for months had higher fatty-acid levels in their milk, with no harm seen in mother or baby.43e-lactation. Evening Primrose So moderate use during breastfeeding is considered little or no risk.44e-lactation. Evening Primrose Herbal supplements in general haven’t been tested in high-quality trials in breastfeeding women,45PubMed. Safety of Popular Herbal Supplements in Lactating Women and the bleeding and seizure cautions still apply after birth.

If you start it, wait until heavy postpartum bleeding has settled. Tell your baby’s doctor you take it, especially if the baby has a health condition, and watch for unusual fussiness or rash. Stop if either appears.