What are two dietary recommendations for a woman who is experiencing nausea and vomiting with pregnancy or morning sickness?

Índice Show

Things you can try yourself
Anti-sickness medicine
54.1 Background
54.1.1 Nausea and vomiting in pregnancy
54.1.2 Impact of nausea and vomiting in pregnancy
54.2 Managing nausea and vomiting in pregnancy
54.2.1 Discontinuing iron
54.2.2 Oral health
54.3 Practice summary: managing nausea and vomiting
54.4 Resources

Nausea and vomiting in pregnancy, often known as morning sickness, is very common in early pregnancy.

It can affect you at any time of the day or night or you may feel sick all day long.

Morning sickness is unpleasant, and can significantly affect your day-to-day life. But it usually clears up by weeks 16 to 20 of your pregnancy and does not put your baby at any increased risk.

There is a chance of developing a severe form of pregnancy sickness called hyperemesis gravidarum. This can be serious, and there's a chance you may not get enough fluids in your body (dehydration) or not get enough nutrients from your diet (malnourishment). You may need specialist treatment, sometimes in hospital.

Sometimes urinary tract infections (UTIs) can also cause nausea and vomiting. A UTI usually affects the bladder, but can spread to the kidneys.

you're vomiting and:

have very dark-coloured urine or have not had a pee in more than 8 hours
are unable to keep food or fluids down for 24 hours
feel severely weak, dizzy or faint when standing up
have tummy (abdominal) pain
have a high temperature
vomit blood
have lost weight

Unfortunately, there's no hard and fast treatment that will work for everyone’s morning sickness. Every pregnancy will be different.

But there are some changes you can make to your diet and daily life to try to ease the symptoms.

If these do not work for you or you're having more severe symptoms, your doctor or midwife might recommend medicine.

Things you can try yourself

If your morning sickness is not too bad, your GP or midwife will initially recommend you try some lifestyle changes:

get plenty of rest (tiredness can make nausea worse)
avoid foods or smells that make you feel sick
eat something like dry toast or a plain biscuit before you get out of bed
eat small, frequent meals of plain foods that are high in carbohydrate and low in fat (such as bread, rice, crackers and pasta)
eat cold foods rather than hot ones if the smell of hot meals makes you feel sick
drink plenty of fluids, such as water (sipping them little and often may help prevent vomiting)
eat foods or drinks containing ginger – there's some evidence ginger may help reduce nausea and vomiting (check with your pharmacist before taking ginger supplements during pregnancy)
try acupressure – there's some evidence that putting pressure on your wrist, using a special band or bracelet on your forearm, may help relieve the symptoms

Find out more about vitamins and supplements in pregnancy

Anti-sickness medicine

If your nausea and vomiting is severe and does not improve after trying the above lifestyle changes, your GP may recommend a short-term course of an anti-sickness medicine, called an antiemetic, that's safe to use in pregnancy.

Often this will be a type of antihistamine, which are usually used to treat allergies but also work as medicines to stop sickness (antiemetic).

Antiemetics will usually be given as tablets for you to swallow.

But if you cannot keep these down, your doctor may suggest an injection or a type of medicine that's inserted into your bottom (suppository).

See your GP if you'd like to talk about getting anti-sickness medication.

It's thought hormonal changes in the first 12 weeks of pregnancy are probably one of the causes of morning sickness.

But you may be more at risk of it if:

you're having twins or more
you had severe sickness and vomiting in a previous pregnancy
you tend to get motion sickness (for example, car sick)
you have a history of migraine headaches
morning sickness runs in the family
you used to feel sick when taking contraceptives containing oestrogen
it's your first pregnancy
you're obese (your BMI is 30 or more)
you're experiencing stress

Visit the pregnancy sickness support site for tips for you and your partner on dealing with morning sickness.

Find maternity services near you

In this video, a midwife gives advice on how to deal with morning sickness during your pregnancy.

Page last reviewed: 13 April 2021
Next review due: 13 April 2024

Nausea and vomiting are common in pregnancy, particularly in the first trimester, with the severity varying greatly among pregnant women. A range of non-pharmacological and pharmacological interventions can be used to assist in managing nausea and vomiting in pregnancy. Women may find these interventions useful, although the evidence for their effectiveness remains inconclusive.

54.1 Background

Nausea and vomiting in pregnancy ranges from mild discomfort to significant morbidity (King & Murphy 2009). Symptoms generally start around 4–9 weeks of pregnancy (Gadsby et al 1993). Nausea and vomiting due to other conditions (eg gastrointestinal, metabolic, neurologic or genitourinary) should always be excluded, particularly in women who report nausea or vomiting for the first time after 10 weeks (Koch & Frissora 2003).

The most severe form of nausea and vomiting in pregnancy is Hyperemesis gravidarum, which is intractable vomiting in early pregnancy, leading to dehydration and ketonuria severe enough to justify hospital admission and intravenous fluid therapy (Bottomley & Bourne 2009).

The cause of nausea and vomiting in pregnancy is not known but is probably multifactorial (Ebrahimi et al 2010). The rise in human chorionic gonadotrophin during pregnancy has been implicated; however, data about its association with nausea and vomiting are conflicting (Weigel & Weigel 1989).

54.1.1 Nausea and vomiting in pregnancy

Prevalence: Nausea is the most common gastrointestinal symptom of pregnancy, occurring in 80–85% of all pregnancies during the first trimester, with vomiting an associated complaint in approximately 52% of women (Whitehead et al 1992; Gadsby et al 1993). Retching (or dry heaving, without expulsion of the stomach’s contents) has been described as a distinct symptom that is increasingly measured separately to vomiting and nausea (Matthews et al 2010).
Timing: Most women report nausea and vomiting within 8 weeks of their LMP (94%), with over one-third (34%) reporting symptoms within 4 weeks of their LMP (Whitehead et al 1992; Gadsby et al 1993). Most women (87–91%) report cessation of symptoms by 16–20 weeks of pregnancy. Although nausea and vomiting is commonly referred to as ‘morning sickness’, only 11–18% of women report having nausea and vomiting confined to the mornings (Whitehead et al 1992; Gadsby et al 1993).
Hyperemesis gravidarum: This condition is much less common, affecting 0.3–1.5% of women (Bottomley & Bourne 2009). Symptoms typically start between 5 and 10 weeks pregnancy and resolve by 20 weeks. However, up to 10% of women will continue to vomit throughout the pregnancy. The hospital admission rate for the condition falls from 8 weeks onwards (Bottomley & Bourne 2009).

54.1.2 Impact of nausea and vomiting in pregnancy

Although distressing and debilitating for some women, nausea and vomiting do not appear to have a negative impact on pregnancy outcomes. A systematic review of observational studies found a reduced risk of miscarriage associated with nausea and vomiting (OR 0.36; 95%CI 0.32 to 0.42) and conflicting data regarding reduced risk for perinatal mortality (Weigel & Weigel 1989). No studies have reported an association between nausea and vomiting in pregnancy and teratogenicity (Klebanoff & Mills 1986).

However, despite reassurance that nausea and vomiting do not have harmful effects on pregnancy outcomes, these symptoms can have a severe impact on a pregnant woman’s quality of life. Two observational studies have reported on the detrimental impact that nausea and vomiting may have on women’s day-to-day activities, relationships, use of healthcare resources and need for time off work (Smith et al 2000; Attard et al 2002).

54.2 Managing nausea and vomiting in pregnancy

The systematic review conducted to inform these Guidelines identified additional evidence that was consistent with the NICE guidelines. The highest quality study, a Cochrane review (Matthews et al 2010) examined 27 trials of interventions including acustimulation, acupuncture, ginger, vitamin B6 and several antiemetic medicines. Systematic review of studies in this area is complicated by the heterogeneity of studies and limited information on outcomes (Matthews et al 2010).

The available evidence suggests the following:

Ginger: While small RCTs have found reduced severity of nausea and vomiting with ginger products (syrup or capsules) (Murphy 1998; Vutyavanich et al 2001; Keating & Chez 2002), there is limited and inconsistent evidence of their effectiveness, although there is evidence that their use may be helpful to women (Matthews et al 2010). Dosages of up to 250 mg four times a day appear to be safe (Vutyavanich et al 2001).
Acupressure, acustimulation and acupuncture: While some evidence from systematic reviews of RCTs (Murphy 1998; Vickers 1996) supports the use of P6 acupressure and it appears to be safe in pregnancy (Smith et al 2000), the evidence on the effectiveness of P6 acupressure, auricular acupressure and acustimulation of the P6 point is inconsistent and limited and there appears to be no significant benefit of acupuncture (P6 or traditional) (Matthews et al 2010).
Pyridoxine (vitamin B6): There is limited evidence to support the use of pyridoxine (Matthews et al 2010) and concerns about possible toxicity at high doses.
Antihistamines: A meta-analysis of 12 RCTs that compared antihistamines ± pyridoxine with placebo or no treatment found a significant reduction in nausea in the treated group (OR 0.17; 95%CI 0.13 to 0.21) (Jewell & Young 2001). A systematic review of three RCTs (n=389) found that phenothiazines reduced nausea or vomiting when compared with placebo (RR 0.31; 95%CI 0.24 to 0.42) (Mazzotta & Magee 2000), although different phenothiazines were grouped and one of the trials recruited women after the first trimester. The bulk of the evidence demonstrates no association between birth defects and phenothiazine use during pregnancy (n=2,948; RR 1.03; 95%CI 0.88 to 1.22) (Mazzotta & Magee 2000; Attard et al 2002).
Other pharmacological treatments: Antiemetic medicines are more likely to have a place in treatment of severe symptoms and the intractable nausea and vomiting of Hyperemesis gravidarum than in the relief of mild or moderate nausea and vomiting (Matthews et al 2010).

It is currently not possible to identify with certainty interventions for nausea and vomiting in early pregnancy that are both safe and effective (Matthews et al 2010). As nausea and vomiting mostly resolves within 16 to 20 weeks with no harm to the pregnancy, prescribed treatment in the first trimester is usually not indicated unless the symptoms are severe and debilitating (BMA 2003).

54.2.1 Discontinuing iron

Iron supplementation may be an aggravating factor in nausea and vomiting. The systematic review conducted for these Guidelines identified a prospective cohort study (Gill et al 2009) in which 63 of 97 (p=0.001) women with severe nausea qualitatively reported an improvement in symptoms after discontinuing iron-containing antenatal multivitamins. If multivitamins are discontinued, consideration should be given to ensuring folate and iodine intake remain sufficient.

54.2.2 Oral health

Nausea and vomiting have the potential to affect oral health and women should be given advice on how to minimise these effects (see Chapter 16).

54.3 Practice summary: managing nausea and vomiting

When

At the first contact with all women and at subsequent contacts for women who report nausea and vomiting.

Who

Midwife
GP
obstetrician
Aboriginal and Torres Strait Islander health worker
multicultural health worker
dietitian
pharmacist.

What

Inform women that nausea and vomiting is not associated with medium or long-term adverse effects: Explain that nausea and vomiting is common in pregnancy, is not necessarily confined to the morning and is likely to lessen by week 16.
Provide lifestyle/diet advice : Acknowledge that nausea and vomiting affects quality of life, and suggest tips on managing nausea and vomiting, including drinking plenty of fluids, eating little and often during the day, getting plenty of rest and avoiding fatty or spicy food. Avoiding iron-containing multivitamins while nausea and vomiting are present may also help.
Discuss non-pharmacological and pharmacological treatments: If the woman asks about treatments for nausea and vomiting, suggest interventions that may help and are thought to be safe, beginning with non-pharmacological approaches. The safety and effectiveness of antiemetics should be discussed with women with more severe symptoms who choose to consider medication.