I'm a little bored with researching nausea and vomiting of pregnancy (NVP). Probably because I'm not pregnant myself and know only one person in the early months of pregnancy right now. I have an acquaintance who is 11 weeks pregnant and seeing some benefit from using molybdenum; her "morning sickness" is mostly stomach discomfort rather than nausea this time around (it's her fifth pregnancy, I believe), which fits my hypothesis that endogenous hydrogen sulfide production in the abdomen is part of a healthy pregnancy but will also tend to cause slower gastric emptying.
I've addressed why many home and medical remedies can ameliorate NVP in accordance with my theory of sulfite accumulation causing NVP. The main medical remedies I haven't addressed are antihistamines (very sedating, though) and dopamine antagonists (can cause heart rhythm abnormalities, movement disorders, etc.), both of which do far more to the body than just help it bear NVP (http://www.uptodate.com/contents/treatment-and-outcome-of-nausea-and-vomiting-of-pregnancy). I'll probably post more later as I stumble across connections between sulfite and these two kinds of medication. For example, there are hints that serotonin and dopamine increase production of hydrogen sulfide, the precursor of sulfite (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3144905/, https://www.ncbi.nlm.nih.gov/pubmed/26593431).
I hope my theory is correct so that multi-effect medications such as antihistamines only rarely need to be used during pregnancy. Sleeping through early pregnancy is better than being conscious and miserable, but most pregnant women would prefer to not have their activities curtailed quite so sharply. A little curtailment is a good thing, to be sure. I think training for a marathon during the period of placental development is unwise at best. That placenta is growing into the uterus's endometrium, and it seems best to not have the uterus rattling up and down constantly during that process. But there's a big difference between sitting down and being asleep.