Ovarian Hyperstimulation Syndrome (OHSS) is a potential complication of fertility treatments, such as in vitro fertilization (IVF), which use hormonal stimulation. This excessive response causes the ovaries to swell and release chemical messengers that increase blood vessel permeability. Fluid leaks out of the blood vessels into surrounding tissues, most commonly the abdominal cavity, leading to symptoms. While most cases are mild and resolve without intervention, severe OHSS poses serious health risks, making it important to know when symptoms require immediate hospital attention.
Classifying the Stages of OHSS
OHSS is typically classified into mild, moderate, and severe categories, sometimes including a critical stage. Mild OHSS is common, affecting about one-third of individuals undergoing controlled ovarian stimulation. It is characterized by mild abdominal bloating, discomfort, and nausea, with ovaries usually enlarged to less than 8 centimeters in diameter.
Moderate OHSS presents with more pronounced discomfort, increased abdominal girth, and sometimes vomiting or diarrhea. Ultrasound imaging often confirms the presence of ascites, or fluid accumulation in the abdominal cavity. Vital signs and kidney function usually remain stable, and management is often handled with close outpatient monitoring, including tracking weight and fluid intake.
Severe OHSS involves significant fluid shifts that compromise bodily functions. Symptoms intensify, including marked abdominal distention, difficulty breathing, and hemoconcentration (a thickening of the blood). Critical OHSS involves potential complications like severe electrolyte imbalance, blood clotting abnormalities (thromboembolism), and organ failure requiring intensive care.
Emergency Symptoms Mandating Immediate Hospital Visit
A rapid progression of symptoms signals that a hospital visit is necessary, especially if discomfort is not relieved by standard pain management. Severe, sudden, or rapidly worsening abdominal pain that is localized or persistent should prompt an immediate trip to the emergency room. This pain can indicate a severe complication, such as ovarian torsion or a ruptured ovarian cyst, requiring urgent evaluation.
Significant difficulty breathing, including shortness of breath, chest tightness, or a rapid breathing rate, warrants immediate medical care. This symptom often occurs when substantial fluid shifts from the abdomen into the chest cavity, creating pressure on the lungs. This fluid shift also leads to signs of dehydration and reduced blood volume, even if the patient feels bloated.
Signs of potential kidney compromise, such as significantly reduced or absent urination (oliguria) or passing very dark, concentrated urine, are serious warning signs. This reduced output indicates that the fluid shift has decreased the effective blood volume circulating through the kidneys. Similarly, rapid weight gain, defined as more than two to three pounds in 24 hours, reflects an accelerating rate of fluid accumulation and requires immediate assessment.
A serious, though rare, complication is the formation of blood clots, or venous thromboembolism. Signs of a clot include pain, redness, or swelling in the leg or calf, or chest pain accompanied by breathlessness. Neurological symptoms, such as fainting, severe dizziness, or confusion, also necessitate emergency care, suggesting severe dehydration or electrolyte imbalances.
Hospital Procedures and Acute Treatment
Upon arrival at the hospital with severe OHSS symptoms, the initial focus is on a rapid assessment of the patient’s stability. Medical staff check vital signs, perform a physical examination, and assess urgency. Diagnostic testing includes blood work to monitor for hemoconcentration, electrolyte imbalances, and the function of the kidneys and liver.
An ultrasound measures the enlarged ovaries and quantifies the amount of fluid (ascites) in the abdominal and potentially the chest cavities. The primary goal of acute treatment is supportive care aimed at correcting fluid shifts. Intravenous (IV) fluid administration is initiated to restore the volume of fluid within the blood vessels, which can become depleted despite external bloating.
Patients are closely monitored, often with a strict accounting of fluid input and urine output to manage fluid balance effectively. If fluid accumulation causes severe respiratory distress, tense abdominal pain, or is unresponsive to IV therapy, a procedure called paracentesis may be performed. This involves using a thin needle under ultrasound guidance to drain excess fluid from the abdominal cavity, providing immediate relief from pressure and improving breathing.
To prevent the elevated risk of blood clots due to blood thickening and reduced mobility, anticoagulant medications may be administered. The patient is kept under close observation until laboratory values stabilize and symptoms substantially improve. This confirms that the fluid leakage has stopped and the body is beginning the resolution phase.