# Hyperemesis Gravidarum

Source: https://www.pregnancypowerhour.com/conditions/hyperemesis-gravidarum
Last updated: 2026-07-15

> Hyperemesis Gravidarum is a severe form of pregnancy nausea and vomiting, distinct from typical morning sickness, requiring medical attention.

Hyperemesis Gravidarum (HG) is a distinct and serious pregnancy condition characterized by extreme nausea and persistent vomiting that goes far beyond typical morning sickness. This is a clinical diagnosis, not simply 'really bad' morning sickness, affecting a small percentage of pregnancies.

## What it is

Unlike the common nausea and occasional vomiting many experience in early pregnancy, HG is defined by significant weight loss (more than 5% of your pre-pregnancy weight), severe dehydration, and an imbalance in your body's electrolytes. These are not symptoms to simply 'push through.' This condition has clear biological mechanisms, often linked to placental hormones and genetics, and is absolutely not caused by psychological factors. Historically, some individuals experiencing HG were unfortunately met with skepticism, but evidence-based understanding has moved far past that.

## What it tends to feel like

If you're experiencing HG, the nausea can be constant and debilitating, making it incredibly difficult to eat or drink. The vomiting can be frequent and relentless, leading to the physical markers mentioned above. Beyond the physical toll, HG can have a profound psychological impact. Research from organizations like the HER Foundation and Evidence-Based Birth highlights elevated rates of anxiety, depression, and even PTSD during and after pregnancies affected by HG. It's a challenging experience that can leave you feeling drained, both physically and emotionally, sometimes contributing to feelings similar to [Pregnancy Anxiety](/conditions/pregnancy-anxiety) or even [Perinatal Depression](/conditions/perinatal-depression).

## What the evidence says helps

Medical treatment is essential for managing HG. This often includes intravenous (IV) fluids to combat dehydration and restore electrolyte balance, as well as antiemetic medications specifically designed to reduce nausea and vomiting. Common options include ondansetron, promethazine, and metoclopramide. In some cases, hospitalization might be necessary to stabilize your condition. If you're struggling to eat, thiamine (Vitamin B1) supplementation becomes critical to prevent a rare but serious complication called Wernicke encephalopathy.

Regarding ondansetron (often known as Zofran), it is widely used and can be very effective. A 2021 analysis in the BMJ noted a very small absolute increase in cardiac septal defects when used in the first trimester. This is an important piece of information to discuss with your care team, as the risk-benefit calculation is a personal one. It's also worth noting that guidelines can diverge; for example, US guidelines tend to be more permissive with first-trimester ondansetron use compared to some European bodies. This is an area where informed decisions, made collaboratively with your provider, are key. Understanding options and potential considerations, much like when navigating concerns like a [Subchorionic Hemorrhage](/conditions/subchorionic-hemohrrage), empowers you in your care.

## Working with your care team

Early and aggressive treatment is crucial. Waiting to see if symptoms improve is no longer considered the standard of care, as early intervention can prevent prolonged suffering and reduce the need for hospital admissions. Your care team — your OB or midwife — is your best resource for developing a personalized treatment plan. They can help you weigh the options for medication, discuss hydration strategies, and monitor your overall health. Advocating for yourself and clearly communicating the severity of your symptoms is vital. Remember, you get to decide what feels right for your body and your pregnancy, supported by evidence-based information and your medical team's guidance.