FAQs

If you are suffering from persistent nausea and/or vomiting which is preventing you from eating and/or drinking then you may be suffering from Hyperemesis Gravidarum (HG). With ordinary nausea and vomiting of pregnancy (NVP), the sickness does not interfere with your ability to eat and drink enough,  you should not be losing weight and you should be able to continue to care for yourself and your family although you may not be feeling too great. With HG, sufferers often need help caring for themselves, never mind look after their family. The illness can be completely debilitating for weeks or even months. Currently in the UK hyperemesis gravidarum is diagnosed at the point of requiring hospital admission, however, research suggests that many more women should come under the diagnosis of HG even though they manage to avoid actual admission to hospital, while other women are experiencing frequent admissions and never receiving the diagnosis of hyperemesis.

Diagnosis is important as you will inevitably become dehydrated and you will need to be admitted to hospital for intravenous rehydration. Starvation is another risk. When your body burns fat for energy, it produces chemicals called ketones which can be detected in your urine. You can monitor your levels of starvation using ketosticks, available from pharmacies. You wee on the stick and it gives you a ketone score. If levels are high, you should tell your doctor or midwife. If you are worried about dehydration and ketone levels and you can't see your doctor or midwife, you can go to A&E.

Another sign of dehydration which may be a criteria for admission is a urine output of less than 500ml in a 24 hour period. It may be worth getting a cheap measuring jug and keeping a fluid balance sheet (downloadable here). Try to monitor your intake as well as output as this is useful information for your doctor or midwife.

The good news is that for the vast majority of sufferers the physical symptoms of HG disappear completely as soon as the baby is born. You should be aware though that it is not unknown for the nausea to persist after birth especially if you have been severely ill. If this occurs, speak to your doctor. For women who suffered persistent, long term nausea and vomiting, it may take some time to restore energy levels and nutritional reserves. Moreover, while the physical symptoms may leave, the trauma of HG can leave an emotional legacy for many women, especially when combined with the rigours of caring for a baby. If you have any concerns, speak to your doctor or midwife. Don't feel that you should just be able to pick yourself up and get on with things, if you're having problems you are entitled to seek support. In particular, Post Traumatic Stress Disorder (PTSD) is not uncommon after severe hyperemesis gravidarum due to the prolonged, relentless and intense suffering of the condition.

Although it is not a guarantee that one hyperemetic pregnancy will lead to suffering HG again in subsequent pregnancies, studies have shown that there is an increased chance of developing hyperemesis gravidarum in subsequent pregnancies if you have had it once already.

It is therefore important that you prepare for a 'worst case scenario'. Please refer to our page on Preparing for another pregnancy and our treatment pages for details of prophylactic treatment.

Generally the reasons why some women suffer from Pregnancy Sickness and not others isn’t very clear, but one thing that is known is that Pregnancy Sickness does not arise from the baby, but from hormones produced by the placenta.

Further information:

Medical research has shown an association between the pregnancy hormone human chorionic gonadotrophin (hCG) and pregnancy, although this association only holds true when several women are grouped together in the investigation, rather than for each individual pregnant woman. In addition, high maternal blood levels of this hormone occur in twin pregnancies and twin pregnancies are generally associated with increased pregnancy sickness. A rare condition in the Western World is a Hydatidiform Mole, in which the afterbirth is abnormal, but more significantly, there is no normal baby present. This condition is also known to be associated with a high maternal human chorionic gonadotrophin blood levels and increased pregnancy sickness. As there is no baby present, the sickness cannot arise from the baby. There is one other pregnancy related condition in which high blood levels of hCG occur in the woman’s blood, but this condition is not associated of itself with any sickness. Therefore, neither the baby nor hCG itself can be the cause of pregnancy sickness. HCG can be considered to be associated with nausea and vomiting of pregnancy (N.V.P.) but not its actual cause.

It is remarkable that the hormone hCG has, by electrophoresis, been shown to occur in at least 5 different isoforms or ‘types’. In very early pregnancy, the type with an ‘acidic basis’ is more prominent, whereas, after 11-15 weeks of pregnancy the more ‘basic’ type of hCG becomes the more prominent of the isoforms. It has been shown that the acidic type of hormone is the most active form of the hormone, but it is more quickly broken down to become ‘inactive’ than the basic type. This active acidic type of hCG has been shown to be present in higher quantities in women who have hyperemesis gravidarum (the most severe form of pregnancy sickness) than in normal pregnancy.

If hCG itself is not causing pregnancy sickness, though associated with the condition, perhaps because the maternal blood level of hCG is rising rapidly in early pregnancy, some other hormone which stimulates hCG production in early pregnancy, may cause pregnancy sickness. At present, we know of eleven locally acting hormones which stimulate the secretion and release of hCG from afterbirth cells. The only two of them known to cause sickness in pregnancy are called Prostaglandin E2 and F2alpha. One further investigation has shown that more Prostaglandin E2 is present in maternal blood when pregnant women are feeling sick than when they are not feeling sick on the same day. Obviously, more investigation is needed into this under-funded and under-researched condition before we can be definite about the association of acidic hCG and Prostaglandin E2 with pregnancy sickness. It may be that we have been able to show there are grounds for believing pregnancy sickness is a physical hormone based condition, rather than purely a somatic or mind over matter reaction to a stressful condition.

There are at least 12 hormones and at least one significant enzyme produced by placental cells which can affect pregnancy sickness. The production of each of these can vary from one pregnancy to the next. Recent medical research has shown the recurrence rate for Hyperemesis Gravidarum in subsequent pregnancies to be as high as 70-80%.

Further information:

To cut a long story short, the pregnancy hormone, human chorionic gonadotrophin (hCG) has been associated with nausea and vomiting in pregnancy (N.V.P) by investigations, which include a number of women. However, there is one rare condition which is associated with high hCG blood levels, but is not associated with any sickness. As N.V.P in early pregnancy is related to rapidly rising maternal hCG blood levels, we need to look for the cause of N.V.P at other locally acting hormones which stimulate the synthesis (production) of hCG. There are, at our present state of knowledge, eleven locally acting hormones or cytokines all produced by placental (often called afterbirth) cells, which stimulate hCG synthesis. There are also at least 5 known variations of hCG itself. The only one of these locally acting hormones, which is known to cause sickness, is a group called Prostaglandins, of which Prostaglandin E2 (PGE2) and Prostaglandin F2 alpha (PGF2a) are constantly present during early pregnancy. There is an enzyme produced in some placental cells called Prostaglandin dehydrogenase (PGDH), which breaks down or inactivates these prostaglandins. The amount of these anti-prostaglandins in placental cells varies from one pregnancy to another and also increases in quantity as the pregnancy progresses.

There are then many hormones produced by the placenta that can vary in quantity from one pregnancy to another and be associated with different degrees of severity of N.V.P in each individual pregnancy. More research and more funding is needed for further progress to be made to explain clearly this surprising and important subject. We may notice that N.V.P recurs similarly from one pregnancy to the next in about ½ - ¾ of succeeding pregnancies in the same person. Furthermore, recent medical research has shown the recurrence rate for Hyperemesis Gravidarum in subsequent pregnancies to be as high as 70-80%.

Yes, about 70-80% of pregnant women who have a normal successful pregnancy have some degree of nausea and vomiting in pregnancy (NVP). However, about 26% of women who do not have any NVP also have a normal successful pregnancy, so it can also be normal to have no NVP.

However, in it's extreme form, Hyperemesis Gravidarum (HG), more serious complications can ensue and HG is therefore considered a complication of pregnancy rather than a normal part of it.

Even severe nausea and vomiting in pregnancy is associated with a good prospect for a successful outcome for the pregnancy. There are no specific complications of pregnancy related to even severe NVP. However, women with severe hyperemesis gravidarum may be assessed for a low birth weight baby, although not a premature baby. The problems with NVP are that repeated vomiting by the ‘mother-to-be’ needs to be carefully watched for signs of her developing dehydration and the persistent nausea can make her feel diabolically ill. Untreated hyperemesis gravidarum carries obvious risks and treatment of this condition is vital to ensure the health of the mother and baby.

This is a very difficult question to answer. The hormone hCG has a variety of 5 different forms. These are made by two enzymes produced by afterbirth cells. Only one form of this hCG is closely related to pregnancy sickness. Maybe this specific form of the hormone is occasionally produced later into the pregnancy?

More information:

We cannot give a definite answer to this important question at present. However, we have mentioned in the short answer that there are at least 5 different forms of the hormone human chorionic gonadotrophin (hCG), the acidic form having the longer half life in maternal blood being the dominant form until the 11 th to the 15 th week of pregnancy. This form of hCG has been related to pregnancy sickness symptoms. It is speculated that this acidic form of hCG is produced within placental (after-birth) cells by the effect of the intracellular enzymes glycosidases and glycosyltransferase acting on intracellular precursors of hCG. Deletion of sialyl-transferase and increased sialidase activity are considered likely causes of the production of the acidic form of hCG. To get a better understanding we need to investigate the blood samples of women who are having these prolonged symptoms of pregnancy sickness to find out if these assumptions bear any relationship to the truth.

The time of cessation of NVP is variable. Yes - NVP can stop before week 12 from LMP in about 60% of pregnant women according to one investigation but in only 27% in another investigation.
Even when NVP starts early after LMP or severely, it usually ends between weeks 12-14 from LMP.
NVP stops quite suddenly in approximately 30% of women.
Please bear in mind though for a few women nausea and vomiting may not stop until the delivery of the placenta.

With hyperemesis gravidarum (HG), the situation is slightly different. Like NVP it is usually worse in the first trimester and can end in weeks 12-14, however, the majority of HG sufferers find that it carries on for longer. The HER foundation have results from a self-reported poll on the duration of nausea and vomiting which shows that only around 11% of women with HG reported that nausea and vomiting had stopped before 15 weeks.  45% of women report that they suffered nausea and vomiting past 30 weeks.   Unfortunately, some women suffer severely for the entire pregnancy. Others find that it improves, but they suffer from nausea and occasional vomiting until birth. To see the full results of the survey go to http://www.hyperemesis.org/mothers/current-research/index.php and click on "Duration of HG" poll, then click on view results.

Despite numerous studies looking at this subject there is no conclusive evidence proving that pregnancy sickness is worse with either sex. Several recent studies have suggested that women suffering with Hyperemesis Gravidarum are more likely to be carrying a girl but the difference is not enough to be significant.

Yes, there is evidence that pregnancy sickness and hyperemesis gravidarum is more common and can be more severe in twin pregnancies.

Pregnancy sickness can have a profound impact on sufferers and coping with it can be a real challenge, particularly if you have small children at home already. Please see our 'Get Help' section for advice on coping strategies and how to access our support network.

Popular opinion says that medications in pregnancy are not safe for the baby and that women must simply put up with nausea and vomiting in pregnancy. There are however a variety of safe treatments available for nausea and vomiting in pregnancy and in its severe form, hyperemesis gravidarum may prove very dangerous if left untreated. Please see our treatment page for further information about what is available.

Seabands: Stimulation of the P6 point, located three fingers breadth above the wrist, has been used for many years to treat nausea from a variety of causes. Trials of a non-blinded randomised nature have shown a decrease of persisting nausea by at least 50%. Bands worn at the wrist (e.g. Sea Bands) that apply pressure may be a simple way of stimulating the P6 point. There are no theoretical concerns about the safety of acupressure in pregnancy.

Ginger: The conclusion from 6 randomised controlled trials with a total of 675 participants was that ginger extract at 1000 mgs per day may be effective treatment for NVP. However the small number of patients in these studies allocated to receive ginger (n=303) may have been insufficient to properly test the safety of ginger with regards to pregnancy outcome. Ginger is a non regulated food product and most preparations available are of variable purity and composition so dose is uncertain. Side effects include heartburn and thromboxane synthetase inhibition i.e. inhibits platelet aggregation.

Others: Some women are greatly helped by alternative medicine, particularly homoeopathy and acupuncture. Some women can claim to have had the illness 'stopped in its tracks' by acupuncture, but success varies between individual patients and it tends to be expensive. These remedies are worth a try if you can afford it but have a back up plan in case it doesn't work.