tummy bug etc with weigh loss - help

[geranium]

I'm starting to get quite concerned about my baby and would be grateful for any suggestions from MNers.
I'm 18 weeks. From about 16 weeks I've developed severe nausea which means I can hardly bear to eat anything other than toast and fruit. This last week I've picked up a stomach bug which keeps appearing, apparently going but leaving severe nausea behind and then reappearing. The upshot is that since I was last weighed at an antenatal appointment (1 December) I seem to have lost around half to three quarters of a stone. Most of it in the last week I imagine.
Obviously, I'm not eating a balanced diet at the moment and in fact today because of a very upset tummy all I will have is rehydration powders. I'm beginning to get very worried about the effect this is having on the baby - particularly the stomach cramps after bad diarrohea (sorry , tmi). Last week I thought I could feel the baby move and this week he/she seems to have gone to ground.
My husband has been to Boots today and is bringing home some vitamin tablets which I hope to be able to keep down. My questions are:

• is this likely to be harming my baby, particularly the weight loss?
  
• is there anything else I can/should be doing?
  
• are all multivitamin brands on sale the same or is there anything I need to look out for?
  
  I haven't been to the GP since I don't imagine she could do much for the tummy bug other than recommend I let it work itself out since it surfaced on Wednesday, disappeared but leaving nausea and then reappeared today. However, I am going to put a note in the surgery for her tomorrow just letting her know what is happening (no chance anyway of an appointment before Xmas).
  
  Grateful for any thoughts.

[feastofsteven]

IMHO (but am in no way medically qualified!)

Go back to the GPs - they may want to do further investigations (such as testing a stool sample) for any infections if this carries on much longer.

As long as you try your best to keep hydrated the baby should be absolutely fine - the baby leeches all nutrients etc on you via the placenta.

Go for Pregnacare or a specifically pregnant women multivitamin, to make sure you don't get too much vitamin A

If you really can't see your GP until after Xmas, speak to your community MW time at surgery or hospital - it's not fair on you to keep on fretting over Xmas.

[geranium]

any further ideas anyone?

[emmatom]

Can just reiterate feasts answer about the weight loss. I lost a stone in first 3 months as I was bed ridden in hospital with back problems.

Midwife really reassured me that baby will take all it needs from you. You are the only on who will suffer.

Most vitamin packs tell you if you should avoid if pregnant.

[Katemum]

The tummy bug shouldn't be doing your lo any harm, it should still take what it needs from you.
Don't just take an ordinary multivit, too much vit a. You need one for pregnancy.
Can you get to see a midwife to check the heartbeat for reassurance?

[geranium]

The pregnancy multivitamin I've picked (chosen at random out of many) is called Sanatogen pronatal. It says it is for pre-, during and post pregnancy. Anyone heard of it? Would you recommend it or are there other brands which are better? and any other suggestions of ways to keep food down? Back on rehydration powders this morning thanks to my tummy.

Thanks

[geranium]

Hmmn, well 'phone consultation with GP. He said that baby should be fine despite my weight loss but then said that it sounded like I had a viral infection and that some viral infections can damage the baby. He suggested I have a blood test now while ill with a follow-up in 4-5 weeks. The results should show what infection I have/had. Also, not to forget to warn the scanner at my 20 week scan that I had had a viral infection at 17/18 weeks presumably so they can look for damage. Now alarmed all over again - worse than before. There was I worried about the weight loss when I should have been worrying about the infection itself. Crickey this pregnancy thing is stressful.

Oh, and he said (slightly more politely) not to worry about the weight loss because I had plenty of extra padding .