Check-up: hyperemesis gravidarum

My wife is pregnant with our first child. At 22 weeks into the pregnancy she is still vomiting and nauseated, and is losing weight. I thought morning sickness was only supposed to last three months.

Nausea and vomiting is common in pregnancy. And, while the condition is known as “morning sickness”, most pregnant women will experience symptoms throughout the day.

It has been estimated that up to 70 per cent of all women get mild to moderate symptoms during the first three months of pregnancy. Formost, these are gone by the fourth month.

Morning sickness is thought to be caused by high levels of oestrogen and human chorionic gonadotropin (HCG), two hormones that help maintain the pregnancy. Nausea and vomiting may be relieved by changing the diet or patterns of eating.

For example, drinking and eating small portions frequently, eating before getting hungry and eating bland foods may help. However, where nausea and vomiting are intense or persistent enough to cause dehydration or weight loss, it is called hyperemesis gravidarum.

Hyperemesis gravidarum is characterised by severe nausea and excessive vomiting during pregnancy. It is different from regular morning sickness, which tends to dissipate after the first trimester.

If a pregnant woman vomits occasionally but continues to gain weight and is not dehydrated, then they do not have hyperemesis gravidarum. The cause of the condition is unknown.

Are there any tests that can confirm the diagnosis?

Blood and urine tests are used to determine whether dehydration is present and to check for electrolyte abnormalities, which can result from dehydration. If hyperemesis gravidarum is confirmed, admission to hospital may be required.

How can it be treated?

Fluids, glucose, electrolytes, and occasionally vitamins may be administered through an intravenous line. Where a woman has been vomiting excessively, fluids and solids are withdrawn for 24 hours. Sedatives, nausea relieving drugsand other medications may be prescribed.

Once the woman is rehydrated and vomiting has subsided, fluids are given orally. When fluids can be tolerated, small portions of bland food are reintroduced. If vomiting does not recur, portion sizes can be increased slowly.

If symptoms return, the treatment is repeated. Very rarely, if weight loss continues and symptoms persist despite treatment, a nasogastric tube may be passed through the nose and down the throat to the small intestine to allow nutrition to be administered.