By Jane Elliott Health reporter, BBC News

Lee felt ill for most of the pregnancy

Lee Lam wants a second child - a little brother or sister for 18-month-old Morgan.

But the thought of embarking on another pregnancy terrifies her.

During her pregnancy with Morgan, Lee was desperately sick. Doctors initially thought it was simply morning sickness, but she knew there was something more seriously wrong.

"I fell pregnant straight after a miscarriage and right from week two I started feeling sick," she said.

Sick

"By week six I had to lie on my bed just facing the ceiling because if I moved I was sick.

"I had to give up work and luckily they were very understanding. I gave up in week two and never went back.

I felt it all through me. It is like extreme travel sickness - it is disorientating and relentless Lee Lam

"Initially doctors thought I had a 24-hour bug and by eight weeks I had been hospitalised twice and needed a drip to rehydrate me."

Lee, who is 33 and from Kent, could not keep food down and by the time she was eight weeks pregnant she had lost three-quarters of a stone (4.8kg).

This was when doctors diagnosed her with hyperemesis gravidarum (HG), which affects about 1% of pregnant women.

"I knew this was not normal morning sickness. I felt it all through me. It is like extreme travel sickness - it is disorientating and relentless.

"You are also more susceptible to conditions such as depression. You don't feel pregnant - you just feel ill.

Morgan was born healthy

"I have heard of people having terminations because they cannot cope with feeling so sick all the time.

"I looked awful and I felt awful. I could not even make some of my ante-natal classes because I felt so sick.

"When you are pregnant they keep telling you to be sure to take your folic acid and make sure you eat the right things, but I could not hold anything down. It was really worrying.

"And it is a very lonely place to be because people keep saying that they have morning sickness too, but I knew what I was facing was so much worse.

"It was only the thought of my baby which kept me going."

Fear

Lee said doctors prescribed her a variety of drugs, but none worked and her condition continued until month seven of her pregnancy.

Luckily, despite Lee's poor health, Morgan thrived and was born a healthy 61bs 5oz (2.9kg).

But Lee said she had suffered so dreadfully that she is really worried about going through a second pregnancy.

I see her playing on her own and I desperately want her to have a brother or sister to play with. It is a very difficult decision to make Lee Lam

"I really want more children, but I have to weigh everything up so carefully.

"Last time it was just me and my husband Steve that I had to consider, but now we have to take Morgan into the equation and how would I cope if I was so sick again.

"No-one can say whether you will get HG in a second pregnancy.

"On an emotional level, it is very hard to put yourself in a position where you could fall pregnant, knowing that in a couple of weeks time you may be so ill you can't function.

"It sometimes seems easier to just be grateful for the one child and leave it at that.

"Then I see her playing on her own and I desperately want her to have a brother or sister to play with. It is a very difficult decision to make."

Dangers

Katrina Erskine, a consultant obstetrician and gynaecologist at London's Homerton Hospital, said HG was basically an exaggeration of normal morning sickness, and can lead to dehydration and significant weight loss.

Women who have HG will not necessarily get it in a subsequent pregnancy Dr Roger Gadsby

In rare instances, it can also cause severe vitamin deficiency-related problems such as Wernicke's encephalopathy, caused by lack of vitamin B1, or even degeneration of the spinal cord.

"To treat it, we recommend rehydration, the administration of anti-emetics (anti-sickness drugs), vitamin supplements, and, rarely, other measures such as steroids," she said.

Dr Roger Gadsby, a GP in Nuneaton, Warwickshire, and chairman of the support group Pregnancy Sickness Support, said that although the condition could be unpleasant, it was no reason not to push ahead with further pregnancies.

He said: "We set up our support group because my colleague had a patient who had such a bad time with HG that she said she would have no further pregnancies.

"But women who have HG will not necessarily get it in a subsequent pregnancy and there is some evidence to show that if women who have experienced HG start feeling mildly to moderately sick in another pregnancy, this can be treated and may not develop into HG."

Help and advice is available, both on the Pregnancy Sickness Support website, and that of a specific HG organisation, Blooming Awful.