Can ovarian stimulation cause ovarian hyperstimulation syndrome?

OHSS ranges from mild abdominal discomfort and bloating to a serious illness that needs specialist monitoring or hospital care. Fertility teams adjust medication and monitor ovarian response to reduce the risk.

Stimulation medicines encourage several ovarian follicles to develop. In OHSS, the ovaries become enlarged and chemical signals make fluid move out of blood vessels, often into the abdomen. This can cause swelling, nausea and pain; more marked fluid shifts can affect circulation, breathing, kidney function and the risk of a blood clot.

Symptoms can begin after the trigger injection or egg collection and may worsen if pregnancy occurs. Mild discomfort after egg collection can have other causes, but new or increasing symptoms should be reported so the fertility unit can judge their significance.

Attend planned blood tests and ultrasound scans, and use every medicine exactly as your fertility team prescribed. Do not change a dose or take the trigger injection at a different time unless the clinic instructs you to do so.

Keep the clinic's daytime and out-of-hours contact details available. If symptoms appear, the team may ask about pain, vomiting, breathing, urine output and abdominal swelling, and may arrange examination, blood tests or an ultrasound. Follow its advice about fluids, activity, pain relief and whether treatment can continue.

Contact your fertility unit promptly for increasing abdominal pain or swelling, persistent nausea, vomiting, reduced or dark urine, rapid worsening of symptoms, or difficulty keeping fluids down. If the clinic is unavailable, use an urgent medical service and say that you recently had ovarian stimulation.

Go to emergency care for difficulty breathing, chest or upper-back pain, fainting, coughing blood, severe one-sided abdominal pain, marked swelling or very little urine. These signs can reflect severe OHSS, a blood clot, internal bleeding or ectopic pregnancy and require immediate assessment.

Ask how your ovarian response is being monitored, which symptoms should trigger an immediate call, and whom to contact outside clinic hours. If your response is high, ask whether medicine doses, the trigger plan, embryo transfer timing or cycle plan may change to protect your health.