No, your baby will take what it needs from your body. When suffering from morning sickness make sure that you drink plenty of water and try to eat little and often. Acupressure bands may help. Vomiting and nausea during pregnancy affects up to 8 out of 10 pregnant women. Hyperemesis gravidarum is extreme nausea and vomiting and can be potentially life-threatening. If you are worried, consult with your GP.
Anti-sickness medication can be prescribed by your doctor but will only be recommended for women suffering from dehydration - symptoms include a very dry mouth and concentrated urine (dark yellow in colour).