Health ConditionsNausea and vomiting of pregnancy is commonly called "morning sickness," but nausea, vomiting, or both may occur at any point during the day. Nausea and vomiting are common experiences in pregnancy, affecting 70–80% of all pregnant women. Despite popular use of the term "morning sickness," NVP (nausea and vomiting of pregnancy) persists throughout the day in the majority of affected women and has been found to be limited to the morning in less than 2% of women.
Nausea and vomiting of pregnancy usually starts before 9 weeks of pregnancy. For most women, it goes away by 14 weeks of pregnancy. For some women, it lasts for several weeks or months. For a few women, it lasts throughout the pregnancy. Symptoms usually peak between 10 and 16 weeks gestation and usually resolve after 20 weeks. Up to 10% of women, however, continue to be symptomatic beyond 22 weeks.
Some women feel nauseated for a short time each day and might vomit once or twice. In more severe cases, nausea lasts several hours each day and vomiting occurs more frequently. Morning sickness can begin between 4 and 8 weeks of pregnancy, and it typically goes away by 16 to 18 weeks of pregnancy.
At the severe end of the spectrum lies hyperemesis gravidarum (HG). Hyperemesis gravidarum is persistent, severe pregnancy-induced vomiting that causes significant dehydration, often with electrolyte abnormalities, ketosis, and weight loss. HG is considered the serious form of NVP, which is reported in 0.3–10.8% of pregnant women. Abdominal pain, fever, or headaches are typically not present in morning sickness.
Nausea during early pregnancy, also called morning sickness, might be a good sign. Studies have shown that pregnant people with nausea and vomiting during the first trimester have a lower risk of miscarriage than do pregnant people without these symptoms. For women suffering NVP, it may be reassuring to know that NVP is associated with less chance of spontaneous abortions and a reduced risk of congenital heart defects.
The pathophysiology of nausea and vomiting during early pregnancy is unknown, although metabolic, endocrine, gastrointestinal, and psychological factors probably all play a role.
Endocrine system: It is believed to be caused by a rapidly rising blood level of a hormone called human chorionic gonadotropin (HCG), which is released by the placenta. It is probably not the HCG itself that causes the nausea. More likely, it is the HCG stimulating the maternal ovaries to secrete estrogen, which in turn causes the nausea. An increase in progesterone relaxes the muscles in the uterus, which prevents early childbirth, but may also relax the stomach and intestines, leading to excess stomach acids and gastroesophageal reflux disease (GERD).
Gastrointestinal system: Abnormal myoelectric activity may cause a variety of gastric dysrhythmias, including tachygastrias and bradygastrias. Gastric dysrhythmias have been associated with morning sickness. The presence of dysrhythmias was associated with nausea while normal myoelectrical activity was present in the absence of nausea. Mechanisms that cause gastric dysrhythmias include elevated estrogen or progesterone levels, thyroid disorders, abnormalities in vagal and sympathetic tone, and vasopressin secretion in response to intravascular volume perturbation — many of these factors are present in early pregnancy.
Olfactory/nervous system: Hyperacuity of the olfactory system may be a contributing factor to nausea and vomiting during pregnancy. Many pregnant women report the smell of cooking food, particularly meats, as triggers to nausea.
GDF15-GFRAL axis (emerging research): The GDF15-GFRAL axis is currently considered by most researchers to be the most likely pathogenic mechanism of NVP and HG. However, since this has only recently been reported, related studies are still few in number. GDF15 is a hormone that causes taste aversion, nausea and vomiting, not just during pregnancy, but also produced by organs under stress and by tumors.
The pathogenesis of NVP has been attributed to multiple factors such as elevated levels of β-hCG, prostaglandin levels (by relaxing the gastroesophageal sphincter), gastric dysrhythmia, vitamin B6 deficiency, and hyperolfaction. Pregnant people who have severe morning sickness, called hyperemesis gravidarum, have higher HCG levels than other pregnant people do. People pregnant with twins or multiples also have higher HCG levels, and they are more likely to have morning sickness too. Estrogen, another hormone that rises during pregnancy, also is linked with more-severe morning sickness.
In a study by Soules et al., even in a subset of women with molar pregnancies in whom levels of hCG in women were 5 to 10 times higher than in controls, no correlation was found. Furthermore, studies have found high levels of hCG to be associated with fetal growth retardation and preterm delivery, whereas NVP appears to be protective for preterm delivery, making it unlikely for hCG to be the sole contributor to the pathogenesis of NVP.
A genetic predisposition has been suggested based on the concordance in monozygotic twins, variation within ethnic groups, and the fact that siblings and mothers of patients with NVP are likely to have experienced NVP themselves. There is now evidence that HG is caused by a combination of genetics and other factors. The greatest genetic risk factor for HG is variation in a gene that codes for the placenta and appetite hormone GDF15.
Psychological factors (depression, anxiety, eating disorders), once considered the only etiology of NVP, might in fact be a result of the NVP. The condition can make it difficult to continue to work or take care of oneself. It can cause anxiety and depression in some women that lingers after the pregnancy.
Certain risk factors for experiencing NVP that have been proposed include decreased maternal age, increased placental mass, genetic predisposition, previous history of HG, multipara, fetal gender, and Helicobacter pylori infection. Risk factors for hyperemesis gravidarum specifically include the first pregnancy, multiple pregnancy, obesity, prior or family history of HG, and trophoblastic disorder.
An increased incidence of infection with Helicobacter pylori (H. pylori) has been observed in women with HG and is now considered to play a role in its pathogenesis. Research found that 90.5% of women with HG were H. pylori IgG positive, compared to 46.5% of controls. A systematic review from 2007 evaluating 14 case-control trials from 1966 to 2007 found a significant association between maternal H. pylori infection and HG in 10 studies. Odds ratios in the studies varied from 0.55 to 109.33. Chronic H. pylori infection is a risk factor for HG and NVP even though it may not be the single cause of the disorder.
NVP has been postulated to protect the embryo by encouraging the mother to avoid potentially harmful or teratogenic foods and beverages. When analyzing embryonic growth, several critical periods are identified in which there is mass proliferation and cell division, resulting in the development of the heart and central nervous system, which are very sensitive. In that period, the fetus is most at risk from damage from toxins and mutagens. These developments occur through week 6–18, which is in the same time frame in which the most nausea and vomiting of pregnancy occurs.
Since thousands of years ago, ginger has been used as a food and herbal medicine in Asia and the Far East, and its medical use is well described in Chinese remedies from 400 BC. Chinese medical texts from the fourth century BCE suggest that ginger was used for treating nausea, diarrhea, stomachache, cholera, toothaches, bleeding, and rheumatism. Since the 16th century, the dried aromatic rhizome of ginger has been used by practitioners of both Indian (Ayurvedic) and traditional Chinese medicine to treat gastrointestinal upsets such as nausea and excessive flatulence.
In Traditional Chinese Medicine (TCM), the fresh and dried rhizome are distinguished by their properties. Fresh ginger possesses the ability to effectively stimulate movement within the body, alleviate the act of vomiting, induce sweating, and provide relief for external syndromes. Fresh ginger is pungent and mild in nature, and it can warm the Middle-jiao to arrest vomiting. Germany's Commission E subsequently approved ginger as a treatment for indigestion and motion sickness.
The most common and well-established use of ginger throughout history is probably its utilization in alleviating symptoms of nausea and vomiting. Mechanistically, the exact mechanism by which ginger affects nausea and vomiting is unclear, but recent studies reveal that active compounds such as gingerols, shogaols, and diterpenoids possess antiserotonergic and 5-HT3 receptor antagonistic effects, which are known to provide nausea relief.
Multiple systematic reviews and RCTs have evaluated ginger for NVP. Four RCTs meeting inclusion criteria for one systematic review all found orally administered ginger to be significantly more effective than placebo in reducing the frequency of vomiting and intensity of nausea. Adverse events were generally mild and infrequent.
A larger systematic review and meta-analysis (PMC, 2014) including twelve RCTs involving 1,278 pregnant women found that ginger significantly improved the symptoms of nausea when compared to placebo (MD 1.20, 95% CI 0.56–1.84, p = 0.0002, I² = 0%). This review suggests potential benefits of ginger in reducing nausea symptoms in pregnancy (bearing in mind the limited number of studies, variable outcome reporting and low quality of evidence). Subgroup analyses seemed to favor the lower daily dosage of less than 1,500 mg.
In a direct comparison RCT, a randomized, controlled equivalence trial involving 291 women less than 16 weeks pregnant was undertaken, with women taking 1.05 g of ginger or 75 mg of vitamin B6 daily for 3 weeks. Ginger was equivalent to vitamin B6 in reducing nausea, retching, and vomiting, averaged over time, with no evidence of different effects at the 3 time points. The use of ginger in early pregnancy will reduce symptoms to an equivalent extent as vitamin B6.
A 2016 clinical evidence review published in PubMed summarized that in the first trimester, ginger might improve nausea and vomiting by about 4 points on a 40-point scale or stop vomiting for 1 in 3 women at 6 days.
A 2025 systematic review and meta-analysis from PMC confirmed that ginger has demonstrated the potential to alleviate symptoms of hyperemesis gravidarum, consistently demonstrating efficacy in reducing NVP across a variety of studies, with minimal side effects. These trials examined various forms of ginger supplementation (capsules, powders, biscuits) and compared them to controls such as placebos, vitamin B6, and metoclopramide.
Evidence strength: Moderate. Multiple RCTs and several systematic reviews support ginger's superiority to placebo for NVP. Evidence quality is rated low to moderate due to variability in study design, dosing, outcome reporting, and small sample sizes. The optimal dose and form remain uncertain. There remains uncertainty regarding the maximum safe dosage of ginger, appropriate duration of treatment, consequences of over-dosage, and potential drug-herb interactions; all of which are important areas for future research.
Vitamin B6 has been known to possess antiemetic effects since 1942. Conventional practitioners have recommended vitamin B6 supplements for many years to treat morning sickness. Pyridoxine's use for NVP has been incorporated into standard obstetric practice in various countries as a first-line or combination agent.
Pyridoxine primarily treats vitamin B6 deficiency and helps alleviate nausea and vomiting during pregnancy. It exists in various forms, including pyridoxine, pyridoxal, and pyridoxamine, which convert into the active coenzyme pyridoxal 5-phosphate (PLP or P5P) in the body.
In two randomized, placebo-controlled trials, 30–75 mg of oral pyridoxine per day significantly decreased nausea in pregnant women who were experiencing nausea. A substudy from a placebo-controlled RCT of the doxylamine–vitamin B6 combination suggested that there is a correlation between PLP levels and PUQE score of morning sickness symptoms when pyridoxine and pyridoxal levels are undetectable, indicating they might be prodrugs of PLP, which may be the active antiemetic form.
A systematic review of clinical trials examining five separate studies of vitamin B6 found a higher mean change in the pyridoxine group (2.9, SD 2.2 vs. placebo 2.0, SD 2.7), and this difference was significant (p < 0.001) on the VAS nausea scale. However, research has found conflicting results regarding using vitamin B6 supplements in treating morning sickness.
Evidence strength: Moderate. Multiple placebo-controlled trials show a significant reduction in nausea scores with pyridoxine. Results are more consistent for nausea reduction than for vomiting. A 2010 Cochrane review noted limited evidence for mild to moderate NVP. Overall evidence is rated as low to moderate quality.
Acupressure is a technique derived from acupuncture, the original Chinese practice of puncturing the body with needles at predetermined key points to cure disease or relieve pain. Acupressure involves applying pressure to selected key points without puncturing the skin. One such point, known as the Neiguan point, located on the flexor side of the forearm just above the wrist, has been utilized in the practice of acupuncture and acupressure as an application point for the alleviation of discomfort and pain.
A prospective study designed to test efficacy of P6 acupressure found that troublesome sickness was significantly less in both the genuine and dummy pressure groups compared with the control series. When data were adversely weighted to compensate for lower incidence of fully completed returns in the active treatment groups, only the P6 group showed a significant reduction in sickness. No side effects occurred in either group.
Acupressure, particularly at the P6 point on the forearm, also presents a promising method for symptom relief, often facilitated by specialized wristbands.
A 2023 meta-analysis of 33 trials and 3,390 patients examining acupressure for NVP found that acupressure was superior to conventional medicine at the reduction of antiemetic drugs (low-quality evidence), but had the same effect as placebo at the effective rate (low-quality evidence). A broader systematic review of CAM therapies concluded that aromatherapy with lemon essential oil, ginger capsules, and pericardial 6 point acupressure were the interventions that proved to be effective.
A review of acupuncture specifically for NVP published in 2021 noted that for non-pharmacological methods, the evidence on the effectiveness of acupressure was limited and the use of acupuncture in pregnant women showed no significant benefits according to a 2010 Cochrane review. More recent evidence has been more positive but remains limited in methodological quality. A 2025 overview of systematic reviews found that there are controversies regarding the consistency of results and the quality of methodologies, and despite low risk of bias across reviews, all were deemed low or critically low in methodological quality.
Evidence strength: Preliminary to moderate. Studies suggest P6 acupressure may reduce NVP symptoms, but the overall body of evidence is rated low quality due to methodological limitations, small sample sizes, and heterogeneous study designs.
Citrus aromatics have been widely employed in folk and traditional medicine across various cultures to soothe digestive upset and nausea, though the specific use of lemon essential oil for pregnancy-related nausea lacks a documented classical textual tradition comparable to ginger.
A double-blinded, randomized controlled clinical trial (100 pregnant women divided into intervention and control groups) examined lemon inhalation aromatherapy. Lemon essential oil and placebo were given to the intervention and control groups, respectively, to inhale as soon as they felt nausea. The nausea, vomiting, and retch intensity were investigated 24 hours before and during four days of treatment using the PUQE-24 scoring tool. There was a statistically significant difference between the two groups in the mean scores of nausea and vomiting on the second and fourth days (p = 0.017 and p = 0.039, respectively).
A subsequent double-blind RCT examined combined lemon and peppermint aromatherapy and found that the combined lemon and peppermint aromatherapy could reduce mild to moderate intensity of nausea and vomiting during pregnancy.
Evidence strength: Preliminary. A small number of RCTs show a statistically significant reduction in NVP scores with lemon inhalation aromatherapy. Evidence is limited by small sample sizes and few trials. The mechanism of action remains unexplained.
Traditionally, peppermint and ginger are recommended for nausea, and can be effective for post-operative nausea. Peppermint has a long history of use in European herbal traditions for digestive complaints including nausea, indigestion, and gastric spasm, frequently prepared as teas, tinctures, or inhaled steam.
Evidence for peppermint aromatherapy specifically in pregnancy-related nausea is mixed. One small study on inhaled peppermint showed no significant effect on nausea during pregnancy compared with saline control. Another study using peppermint inhaled aromatherapy on 60 pregnant women showed that mint aromatherapy is not effective in reducing NVP, a finding that might be partly due to the small sample size. Conversely, a study using the combination of aromatherapy with essential oils of peppermint and lavender suggested that the combination reduced the severity of NVP, increased energy levels, and reduced fatigue in pregnant women.
Evidence strength: Weak and inconsistent. Published trials for peppermint aromatherapy in pregnancy-related nausea are few, small, and produce conflicting results. Evidence is insufficient to draw conclusions.
It is important to eat what you can in small, frequent meals throughout the day, aiming especially to eat something small in the morning. Going too long between meals and feeling hunger pangs can worsen nausea, so eating small meals regularly can help keep food in the belly. Eating small meals is less taxing on the digestive system than eating fewer, larger meals.
Research has specifically examined macronutrient composition. A landmark 1999 study by Jednak et al. found that protein-predominant meals reduced nausea and gastric slow-wave dysrhythmic activity more than carbohydrate or fat meals of equal calories. A 2025 systematic review in Foods confirmed this and recommends distributing protein across five smaller meals per day to optimize gastric motility. The mechanism is straightforward: protein stabilizes blood sugar more effectively than carbohydrates, preventing the reactive hypoglycemia that triggers nausea.
Simultaneously, dry, easily digestible carbohydrates have a low risk of upsetting the stomach — bagels, dry cereal, and dry toast without butter seem to help with morning sickness.
There is some evidence that mothers who are low in certain nutrients or who follow less nutrient-dense diets may be more susceptible to morning sickness. A review of 56 studies from 21 countries found a correlation between dietary patterns and morning sickness. High intake of sugars, sweeteners, stimulants (like caffeine), and certain animal products was linked to increased nausea and vomiting. It was also found that people who consumed diets rich in whole grains and legumes had a reduced likelihood of experiencing these symptoms.
Morning sickness is related to diets low in cereals and high in sugars, oil crops, alcohol, and meat, according to the Wikipedia synthesis of epidemiological literature.
Fried or fatty foods should be avoided, as they take longer to leave the stomach, meaning they are more likely to contribute to feelings of nausea. Staying hydrated is essential, but drinking large amounts at once can trigger more nausea or vomiting. Cold foods may be easier to include than warm foods, which typically have stronger smells and can trigger a nausea episode.
Maintaining adequate fluid intake is emphasized across clinical and institutional guidance for NVP. Fluid losses from vomiting increase the risk of dehydration. Hyperemesis gravidarum is persistent, severe pregnancy-induced vomiting that causes significant dehydration, often with electrolyte abnormalities, ketosis, and weight loss. Sipping fluids in small amounts between meals rather than with meals is a commonly discussed strategy in clinical literature to minimize gastric distension while maintaining hydration.
Morning sickness seems to reduce energy intake by decreasing appetite and changing food preference. Adequate nutrient intake during pregnancy is important for the health of both mother and fetus. Women with severe or prolonged NVP are at risk for nutritional deficiencies, as dietary diversity typically declines during symptomatic periods.
Studies show that H. pylori infection, most likely acquired before pregnancy, is related to hyperemesis gravidarum, the most serious form of NVP. During the last decade, it has been well established that H. pylori infection is related to worsening GI health. Gastrointestinal health prior to conception may therefore be a modifiable risk factor for NVP severity. Lifestyle habits affecting gut microbiome composition and H. pylori acquisition have been proposed as areas for further study.
Doxylamine succinate is an antihistamine that, in combination with pyridoxine (vitamin B6), constitutes the only FDA-approved medication (Diclegis/Diclectin) specifically indicated for nausea and vomiting of pregnancy. ACOG recommends the doxylamine-vitamin B6 combination with Level A evidence as first-line pharmacotherapy for NVP. A phase III randomized, double-blind, placebo-controlled trial supported FDA approval in 2013.
Ginger is among the most evidence-backed natural remedies for morning sickness (nausea and vomiting of pregnancy, NVP). A 2014 systematic review and meta-analysis of 12 RCTs involving 1,278 pregnant women concluded ginger could be considered a possibly effective alternative for NVP. Multiple individual RCTs showed significant reductions in nausea intensity compared to placebo. ACOG states that ginger has shown beneficial effects and can be considered a non-pharmacologic option for NVP.
Lemon (Citrus limon) aromatherapy has been studied in a double-blind, randomized, placebo-controlled clinical trial of 100 pregnant women, which found statistically significant reductions in nausea and vomiting scores on days 2 and 4 of treatment (P=0.017 and P=0.039) versus placebo (PMC4005434). A survey found 40% of pregnant women have used lemon scent to relieve NVP, and 26.5% reported it effective. A 2020 RCT also showed combined lemon-peppermint aromatherapy reduced mild-to-moderate NVP.
Peppermint aromatherapy has been tested in a placebo-controlled RCT for nausea and vomiting of pregnancy (NVP), showing significant reductions in severity. Effect sizes are modest and evidence certainty is low, partly due to blinding challenges inherent to aromatic interventions.
Peppermint (Mentha piperita) is listed as a treatment for morning sickness in the British Herbal Pharmacopoeia and is recognized by the American Pregnancy Association as 'likely safe' and helpful in relieving nausea/morning sickness. Clinical trials of peppermint aromatherapy in pregnant women have shown reductions in nausea and vomiting scores, though evidence is mixed. A quasi-experimental study (PMC6753788) of 66 pregnant women found mint aroma significantly reduced overall Rhodes nausea/vomiting index scores (P<0.001) versus placebo.
Vitamin B6 (pyridoxine) is a first-line pharmacologic recommendation for NVP per ACOG. Two randomized placebo-controlled trials showed 30–75 mg/day of oral pyridoxine significantly decreased nausea in pregnant women. The NIH Office of Dietary Supplements confirms its use for morning sickness. Combined with doxylamine, it is FDA-approved (Diclegis) for NVP with an associated 70% reduction in nausea and vomiting in randomized trials.
Cardamom is used in Ayurvedic and South Asian traditional medicine for nausea and vomiting, including morning sickness in pregnancy. Traditional Sudanese medicine also records cardamom use for post-anesthesia nausea and general nausea/vomiting relief. No controlled human RCTs specifically assessing cardamom for morning sickness in pregnancy have been published.
Chen Pi is a well-established TCM remedy for morning sickness, classified as treating nausea and vomiting related to pregnancy (Spleen-Stomach disharmony). It is frequently prescribed in combination formulas by TCM practitioners for pregnancy-related nausea.
Traditional Western herbalism and Eclectic medicine document peach leaf as a remedy for pregnancy-related nausea and vomiting (morning sickness). Dosage must be carefully monitored due to the leaf's diuretic action. No clinical trials exist.
Perilla stems are a documented TCM remedy for morning sickness (pregnancy-related nausea and vomiting) and 'restless fetus.' This use appears in multiple classical Chinese medical texts. No specific human RCT data for morning sickness with isolated perilla have been identified.
Raspberry leaf has a long traditional use for morning sickness and pregnancy-related nausea, documented across Native American and European midwifery traditions. Multiple herbalists and midwives have recommended raspberry leaf tea throughout pregnancy for nausea relief. The evidence base is entirely traditional; no controlled clinical trials have assessed raspberry leaf specifically for nausea of pregnancy.
Wild yam was traditionally used by herbalists to treat nausea and morning sickness in pregnancy, largely on the basis of its antispasmodic action on smooth muscle of the gastrointestinal tract. PeaceHealth and other institutional sources document this traditional use dating to the 18th–19th centuries. No clinical trials have assessed its safety or efficacy for morning sickness.
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