Nausea and Vomiting
Nausea and vomiting during pregnancy (NVP) occurs commonly with a prevalence of 50–80% for nausea and up to 50% for vomiting and retching. The pathophysiology of NVP is most likely multifactorial. Hypotheses include psychological factors, evolutionary adaptation, hormone alterations, genetic inheritance, infection, and gastrointestinal dysfunction. Differential diagnosis depends on the time of onset. Typically, NVP abates by 9–10 weeks’ gestation. NVP is a clinical diagnosis of exclusion after other gastrointestinal, medical, drug‐induced, or surgical conditions have been ruled out. Treatment begins with prevention which includes multivitamins and dietary and lifestyle changes. Acupressure at the Nei Guan acupoint has been proposed to alleviate symptoms of NVP. The combination of vitamin B6 (pyridoxine) and doxylamine is the recommended first‐line treatment for NVP. Persistent nausea and vomiting for three weeks or longer may result in a deficiency of vitamin B1 (thiamine) leading to Wernicke encephalopathy.
