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Pregnancy is a time of dramatic transitions. Body systems that once sustained a single human now support two. Organs, blood vessels, body chemistry, and even the solid supporting structures of a woman's body all go through changes; in the meantime, the fetus's body grows from a tiny bundle of cells to a full-sized baby.
It's no wonder that women feel the desire for remedies to help with these transitions. Since ancient times, women have tried herbs and other natural treatments to ease discomfort or assist with pregnancy, childbirth, and breastfeeding. However, pregnancy is also a circumstance when the potential risk of any treatment rises dramatically. Seemingly benign medications—even natural ones—have been found to cause birth defects or increase the risk of complications. Some traditional remedies, such as blue cohosh for labor stimulation, must be discarded for safety reasons.
Thorough study is needed before any treatment can be considered absolutely safe in pregnancy—and in many cases this research may never been done due to insurmountable ethical consideration regarding the safety of the fetus. It's important to talk with your doctor before deciding to use any treatment, whether it is natural or conventional.
Principal Proposed Natural Treatments TOP
Many natural treatments have shown promise for conditions related to pregnancy. In this section, we discuss those with the most scientific support. However, treatments for nausea and vomiting of pregnancy and preeclampsia are not discussed here; instead, they are addressed in separate articles. Breastfeeding support also has an article of its own.
Note: The safety of the following treatments has not been confirmed, except for nutrients such as vitamins and minerals, for which appropriate dosages for pregnancy have been established. For more information on potentially harmful natural treatments, see Herbs and Supplements to Avoid During Pregnancy and Breastfeeding.
Increased pressure from the expanding abdomen and other factors can lead to pooling of fluid in the legs, a condition called venous insufficiency (closely related to varicose veins).
Venous insufficiency/varicose veins occur outside pregnancy as well, and a wide variety of natural treatments have shown promise in their treatment, including buckwheat, butcher’s broom, citrus bioflavonoids, gotu kola, horse chestnut, oligomeric proanthocyanidins (OPCs), and red vine leaf. These are discussed in the Venous Insufficiency article.
Only one natural treatment, oxerutins, has been studied in a double-blind trial enrolling pregnant women with venous insufficiency.1 In this study of 69 women, researchers found oxerutins more effective than placebo.
For more information, see the full Oxerutin article.
A double-blind study enrolling 97 pregnant women found oxerutins (1,000 mg daily) significantly better than placebo at reducing the pain, bleeding, and inflammation of hemorrhoids.13 Evidence for citrus bioflavonoids is limited to one open trial.12 Other natural treatments for varicose veins are often recommended for hemorrhoids as well, although research on their use for this condition in pregnancy is lacking.
For more information, see the article on Hemorrhoids.
Anemia is common during pregnancy, usually due to deficiency in iron. However, iron supplements can be hard on the stomach, thereby aggravating morning sickness. One study found evidence that a fairly low supplemental dose of iron—20 mg daily—is very nearly as effective for treating anemia of pregnancy as 40 mg or even 80 mg daily, and is less likely to cause gastrointestinal side effects.112 (Interestingly, 20 mg daily is lower than the amount contained in standard prenatal vitamins.)
Pregnant women who are not anemic should not take more than the recommended daily allowance of iron in pregnancy, as excess iron intake may be harmful both for pregnant women and their unborn children.14-16
Interestingly, one study suggests that iron plus folate is more effective for the treatment of iron-deficiency anemia in pregnancy than iron alone, even in women who do not appear to be folate-deficient.17
Prevention of Neural Tube Defects and Other Birth Defects TOP
Folate supplements can help prevent a serious and common type of birth defect known as neural tube defects (NTDs).18-20 Folate, or folate plus multivitamin/multimineral supplements, may help prevent other birth defects as well, including cleft palate and anomalies of the heart and urinary tract.108 A systematic review of five trials involving 6,105 women reinforced the evidence that folate supplementation can prevent NTDs in both women who have had a baby with an NTD and those who did not.124 Participants took daily doses between 360 mcg to 4 mg with or without additional supplements. There was not enough information, though, to say whether folate can reduce the risk of developing other conditions, like cleft lip or cleft palate.
Other Proposed Natural Treatments TOP
Other natural remedies have been recommended for treating discomforts and complications of pregnancy or decreasing risks to the baby.
Castor bean oil was noted by the ancient Egyptians to stimulate labor, and it is still used by some conventional physicians and midwives to induce contractions—for example, if labor does not occur spontaneously after the water has broken. A recent controlled trial in 100 pregnant women compared oral castor oil to no treatment and found that 57.7% of those given castor oil began labor within 24 hours, compared to only 4.2% of those without treatment.23 Other preliminary studies also suggest that castor oil may help.24,25 Unfortunately, castor oil is a strong laxative, and diarrhea is a nearly universal effect—not a particularly pleasant experience during childbirth.
In addition, considering how common this treatment is, research on its safety and effectiveness is surprisingly scant. One case of a potentially fatal complication linked to use of castor oil has been reported, though some have questioned whether the castor oil was responsible.25,26 In addition, an observational study of South African women found that those self-treating with castor oil and/or other traditional herbs had a higher incidence of meconium (fetal feces) in the amniotic fluid, a sign of fetal distress.27
Acupuncture and Acupressure
A number of studies, including a 2011 review of 13 trials, found evidence that acupuncture is helpful in reducing labor pain.28,29,94,109,221,224 In a study involving 212 women in active labor, researchers found that, in countries where epidural anesthesia is not available, acupuncture can help to reduce pain compared to standard care early in labor.217
Not all of the evidence to support the use of acupuncture to treat labor pain has been high-quality, though.28,29,94 And there have been some studies that have contradicted this conclusion. For example, in one study, sterile water injections were found to be more effective than acupuncture for lower back pain and relaxation during labor. It is unclear whether or not the patients in the study knew which treatment they were receiving at the time.115 And, in a placebo-controlled trial, real acupuncture was no better than sham acupuncture in relieving pelvic pain prior to labor.119 A carefully conducted review of 10 randomized controlled trials involving 2,038 woman was unable to uncover consistent evidence of acupuncture's effectiveness for labor pain either alone or in combination with other treatments.122 In one study involving 60 women, postoperative acupuncture or electro-acupuncture reduced pain within the first 2 hours (but no longer) and demand for pain medication within the first 24 hours after cesarean section.121 And in a study involving 105 women giving birth to their first baby, there was no difference in the need for pain relief between the women receiving real or sham acupuncture.218
A study of 45 pregnant women found that women who received acupuncture on the mathematically calculated birth “due date” gave birth sooner than those who did not.30 However, this trial used a no-treatment control group instead of sham acupuncture, making its results unreliable. Another study suggested that the use of acupuncture may help stimulate normal term labor.107 On the other hand, a third study of 106 women with premature rupture of membranes (“water breaking” too early) found that acupuncture did not effectively speed up delivery.113 It should be noted that none of these 3 studies used sham (fake) acupuncture as a control, making their results unreliable. However, in a subsequent trial that attempted to address this problem, real acupuncture administered for 2 days prior to a planned induction of labor (artificial stimulation of labor) was no better than sham acupuncture at preventing the need for induction or shortening the time of labor.120
Two studies suggest that acupuncture and associated therapies can help "turn" a breech presentation.96,97 In 2008, researchers published a review of 6 randomized controlled trials that investigated acupuncture-like therapies (moxibustion, acupuncture, or electro-acupuncture) applied to a specific point (BL 67). They concluded that these therapies were effective at decreasing the incidence of breech presentations at the time of delivery.118 Again, however, not all of these studies employed a sham acupuncture group for comparison.
According to a small, randomized trial, acupuncture may also help to reduce pain after labor in women undergoing an episiotomy.225
Other Natural Treatments
One double-blind, placebo-controlled trial evaluated the effects of red raspberry in 192 pregnant women.32 Treatment (placebo or 2.4 g of raspberry leaf daily) began at 32 weeks of pregnancy and was continued until the onset of labor. The results failed to show any statistically meaningful differences between the groups. Red raspberry did not significantly shorten labor, reduce pain, or prevent complications.
Blue cohosh is a toxic herb and should not be used. One published case report documents profound heart failure in a baby born to a mother who used blue cohosh to induce labor.33 Severe medical consequences were also seen in a child whose mother took both black and blue cohosh.34
Researchers have also focused on the potential benefits of massage therapy.86-88,226 An analysis of 5 randomized trials, including 326 pregnant women, compared massage therapy with usual care during childbirth.226 (One study compared massage to music therapy in addition to usual care.) Those in the massage therapy groups reported feeling less labor pain and/or anxiety. These favorable results are limited by the absence of an adequate control group in any of the studies.
Evidence has been mixed regarding whether aromatherapy is helpful during childbirth. In a large controlled trial involving more than 600 participants, lavender oil failed to improve pain after childbirth.89 But, a randomized controlled trial involving 251 pregnant women did find evidence that aromatherapy may help reduce the perception of pain during labor and possibly reduce the risk of a newborn needing intensive care.219 In contrast, a review of 2 randomized trials failed to find a positive effect. In the larger of the two studies, 513 women were randomized to receive aromatherapy ( Roman chamomile, clary sage, frankincense, lavender, or mandarin essentials oils) or standard care. Different methods were used to expose the women to the oils, like applying a compress, giving a massage, or using a footbath. There were no differences between the two groups in level of pain, rate of cesarean section, or use of pain medication.220
For a discussion of homeopathic approaches to pregnancy support, see the childbirth support article in the in the Homeopathy Database.
Constipation frequently occurs during pregnancy, for reasons that are not entirely clear.
Fiber supplements, such as psyllium seed, are commonly recommended for the treatment of constipation in pregnancy because of their apparent safety. Flaxseed is another high-fiber seed, and alternative practitioners often recommend it. However, flaxseed contains estrogen-like substances that might pose hazards to the fetus; one study found an effect on reproductive organs and function in baby rats whose mothers ate large amounts of flaxseed during pregnancy.35
Other natural remedies for constipation during pregnancy include dandelion root36 and a combination of glucomannan and lactulose.37 However, there is no meaningful evidence to indicate that they are effective.
Note : Avoid use of powerful laxatives, including natural remedies such as buckthorn, cascara, rhubarb, castor bean oil, and senna, as these can induce uterine contractions.36 (See the Assisting Childbirth section above.) The traditional remedy yellow dock, though milder, might warrant similar caution.36,38
Leg Cramps TOP
Pregnant women sometimes experience painful leg cramps. A double-blind study of 73 women with this symptom found that magnesium was significantly more effective than placebo in decreasing their distress.39
Calcium has also been studied for this problem, but research so far gives little indication that it helps.40-42 A combination of vitamins B1 and B6 has also been suggested for leg cramps, but evidence that it helps remains minimal.43
Prevention of Prematurity and Miscarriage TOP
Interesting though not entirely consistent evidence suggests that use of fish oil or its constituents by pregnant women might help prevent premature births.50,51,90,99,110 Double-blind studies have evaluated the minerals calcium,52-54zinc,55-58 and magnesium59-61 for this purpose as well, but the results have been mixed. A number of trials suggest that anemia is linked to prematurity; however, evidence as to whether iron supplements can help remains inconclusive.54,62
Numerous studies have investigated the effects of vitamin supplementation on prematurity and/or miscarriage. In a review of several studies, folate was not found to be effective for preventing premature birth.63 One study failed to find vitamin C helpful for preventing premature birth.95 However, another study found that vitamin C (100 mg/day after 20 weeks of pregnancy) helped prevent early rupture of the membranes ("water breaking").100 Another study suggested that the use of vitamin E (400 IU daily) and vitamin C (500 mg/day) after premature rupture of membranes helped to hold off delivery by several days.101
Low levels of vitamin B12 may increase risk of miscarriage, and B 12 supplements may help.93 However, despite this limited evidence of benefit, a more recent review of 28 trials involving over 98,000 pregnancies failed to show that vitamin supplements of any kind (starting at 20 weeks gestation) prevent miscarriage or stillbirth.216
Prevention of Low Birth Weight TOP
Babies born below a specific weight (5-½ pounds)—called low birth weight—are at greater risk for complications.
A recent meta-analysis of 7 controlled studies looked at the effects of calcium supplementation on birth weight.64 These studies predominantly focused on preventing hypertension and/or preeclampsia in the mother, both of which can result in low-birth-weight babies. Overall, calcium appeared to decrease the percentage of babies weighing less than 5 pounds 8 ounces.64 However, other analysts looking at a somewhat different group of studies came to the opposite conclusion.65,66
Quite a few double-blind studies have examined zinc58,67-72 as well as magnesium59,60,73 for preventing low birth weight, with mixed results. Results have been similarly mixed in other controlled trials of folate61,74 and fish oil or one of its fatty acids.50,65,75Vitamin D and B vitamins have also been proposed, but so far evidence of their usefulness is weak.54,76
Several decades ago, iron was believed to be helpful in preventing low birth weight. However, a recent large-scale unblinded study of well-nourished women found that routine iron supplements in pregnancy had no effect on birth weight.77 In addition, as previously noted, iron supplementation in pregnant women who are not anemic may not be good for either mother or baby.
Other Uses of Natural Treatments TOP
A common problem in pregnancy is an increased tendency toward swollen or bleeding gums—a condition known as gingivitis. Two, small, double-blind studies suggest that folatemouthwash may help. However, folate supplements do not appear to be especially effective against gingivitis.44,45
Healthy Mental Function in Children
Folate has also been studied for its possible role in the intellectual development of children. In one trial, researchers compared children whose mothers took daily folate and iron supplements while pregnant with those who did not.215 At age 7-9, the children whose mothers did take the combination supplement scored higher on intellectual tests. It is unknown whether or not the folate, iron, or both contributed to this benefit, although the study took place in an area where iron deficiency is common (rural Nepal).
A condition called intrahepatic cholestasis may occur during pregnancy, causing jaundice and other complications. Preliminary evidence suggests that the supplement s-adenosylmethionine (SAMe) might be helpful for preventing this.48,49,103-105
One placebo-controlled study of 30 women suggests that the mineral chromium may be useful for gestational diabetes, the term for diabetes that occurs during pregnancy.46Vitamin B6 has also been proposed for this condition, but evidence in support of its effectiveness is minimal.47
Prevention of Miscarriage
A small preliminary study found that fish oil was significantly more effective than placebo at alleviating postpartum depression.117 However, other studies have failed to find either fish oil or one of its chief components, docosahexaenoic acid (DHA), helpful for preventing perinatal (including postpartum) depression.98,116 For example, a large study involving 2,399 women found that fish oil capsules—a combination of DHA 800 mg/day and eicosapentaenoic acid (EPA) 100 mg/day—did not prevent postpartum depression.123
Cognitive and Visual Function in Children
Herbs and Supplements to Avoid During Pregnancy TOP
For information on this important topic, see Herbs and Supplements to Avoid During Pregnancy and Breastfeeding.
References[ + ]
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Last reviewed July 2012 by EBSCO CAM Review Board
Last Updated: 7/25/2012