Ovarian hyperstimulation is a very important complication that can occur in patients undergoing ovarian stimulation treatments. Risk factors would be the development of 15 follicles and elevated estrogen levels. However, the trigger for ovarian hyperstimulation syndrome is the administration of HCG. This is the hormone that is used to induce the final maturation of the ovules and ovulation, whose better-known trade name is Ovitrelle.
What the HCG would produce is the release of a whole series of substances that cause the exit of water and proteins from the inside of the blood vessels to the abdominal cavity. The consequence is a decrease in the volume of fluid within the blood vessels, responsible for the symptoms of ovarian hyperstimulation syndrome: low blood pressure, decreased urination, accumulation of fluid in the abdomen (ascites), increased viscosity of blood and alteration of blood components.
Ovarian hyperstimulation syndrome is rare in artificial insemination (AI) treatment, as low doses of hormonal medication are often used. The main reason for this is that AI, unlike IVF, only aims to achieve the growth of between 1 and 4 follicles.
It is true that women with PCOS can respond even to very low doses of medication. However, if during an artificial insemination treatment more than 3-4 follicles grow (or even less depending on the characteristics of the patient), the gynaecologist will indicate the cancellation of the treatment to avoid the risk of multiple pregnancies. In this way, by not administering HCG, ovarian hyperstimulation syndrome will not develop.