Snapshot A 25-year-old primigravida is pregnant with twins at 11 weeks of gestation. She is experiencing daily nausea and vomiting of moderate intensity that is worse in the morning. She has tried nonpharmacologic therapies with limited success. She has also tried drinking and eating small amounts at a time, and staying away from odors that make her feel nauseous. Labs reveal a hypochloremic metabolic alkalosis. Introduction Overview a severe form of morning sickness excessive nausea/vomiting during pregnancy typically during first 2-3 months of pregnancy but may persist throughout pregnancy Epidemiology Incidence 0.3-6% of pregnancies Demographics higher rates in younger, primigravid women increased prevalence in Western countries and urban areas less common in Africa and Asia Risk factors history of motion sickness history of migraines history of nausea/vomiting from estrogen-based medications women with heightened sense of smell or taste multiple gestation hydatidiform molar pregnancy prior history of hyperemesis gravidarum gastrointestinal disorders acid reflux ETIOLOGY Pathogenesis unclear etiology potentially related to hormones such as hCG, estrogen, progesterone possible genetic component increased rate of hyperemesis gravidarum in women whose mothers and/or sisters also suffered from hyperemesis gravidarum Presentation Symptoms daily nausea and vomiting weight loss dehydration dizziness reduced urination symptoms may occur at any time of day despite name “morning sickness” Physical exam weight loss >5% of pre-pregnancy weight signs of dehydration orthostatic hypotension tachycardia delayed capillary refill time dry mucous membranes decreased skin turgor Studies Comprehensive metabolic panel hypokalemia hypochloremic metabolic alkalosis elevated serum bicarb elevated serum blood urea nitrogen (BUN) sign of hypovolemia and dehydration abnormal liver enzymes in 50% of hospitalized women with hyperemesis Ketones present in urine or serum due to reduced nutritional intake and frequent emesis Urine specific gravity elevated due to dehydration Hemoglobin/hematocrit increased due to hemoconcentration from dehydration Differential Hydatidiform molar pregnancy key distinguishing factors “snowstorm” appearance on ultrasound abnormally elevated β-hCG Preeclampsia key distinguishing factors hypertension proteinuria HELLP syndrome key distinguishing factors hemolysis low platelets Treatment Behavioral lifestyle modifications eat small meals/snacks often eat as soon as hungry or even before feeling hungry aim for high protein/carbohydrate foods that are low in fat avoid spicy, greasy, or acidic foods drink cold, clear beverages and drink between meals rather than during meals avoid lying down right after eating Medical intravenous fluids indications hypovolemia/dehydration modalities bolus up to 2L lactated ringers over 3-5 hours can use normal saline if only mild symptoms of dehydration maintenance fluids D5 ½ normal saline with potassium must also replace any low-level vitamins thiamine, calcium, magnesium anthistamine (H1 antagonists) indications first-line treatment for vomiting during pregnancy modalities doxylamine-pyridoxine first-line dimenhydrinate, meclizine, diphenhydramine if doxylamine-pyridoxine ineffective dopamine antagonists indications if continued vomiting after use of antihistamine modalities metoclopramide, promethazine, prochlorperazine seratonin antagonists indications if continued vomiting after use of other first and second-line medications small risk of fetal cardiovascular anomalies modalities ondansetron acid-reducing agents indications used as adjuvant therapy with anti-emetics modalities antacids containing aluminum of calcium H2-receptor antagonists ranitidine, cimetidine Complications Dehydration Prognosis no harm to fetus excellent prognosis if dehydration addressed