Ovarian Hyperstimulation Syndrome (OHSS)

Ovarian hyperstimulation syndrome (OHSS) is a reaction to fertility drugs that overstimulate the ovaries. It is an iatrogenic complication, one caused by the treatment itself. It occurs most often during egg-retrieval cycles for ART. High doses of hormone drugs (gonadotropins) make many follicles grow at once. A trigger injection of human chorionic gonadotropin (hCG) then sets off a surge of chemical signals. One of these signals, vascular endothelial growth factor, makes small blood vessels leak. Fluid moves out of the bloodstream and into the abdomen and chest. The effects range from mild bloating to dangerous blood clots.¹ Mild OHSS is common. Severe OHSS requires hospital care. It can cause fluid in the abdomen (ascites), fluid around the lungs (pleural effusion), thickened blood, and strain on the kidneys. Clinicians have long graded OHSS by severity.² Current major professional society guidelines address its prevention and management.¹

Women with polyendocrine metabolic ovarian syndrome (PMOS), formerly polycystic ovary syndrome (PCOS), face the highest OHSS risk. Ovaries in PMOS / PCOS contain many small resting follicles (antral follicles). This high follicle count is part of the definition of ovaries in PMOS / PCOS. It is also the feature that predicts a strong overreaction to fertility drugs. A woman with PMOS / PCOS who is offered ART deserves a clear discussion of OHSS risk. Both partners need accurate risk information before any decision.

OHSS is mainly a problem of the high-dose drug regimens used in ART. In those cycles, the goal is to grow as many follicles as possible for egg retrieval. NaProTechnology, NeoFertility, and related restorative approaches work from a different goal. They use low-dose hormonal support matched to problems found in the charted cycle. They do not try to overstimulate the ovaries. Fewer growing follicles means less of the process that sets off OHSS. Still, any cycle that uses gonadotropins carries some OHSS risk. Rarely, OHSS follows the oral drug clomiphene citrate. It has even occurred with no drugs at all. For this reason, clinicians who use gonadotropins within NaProTechnology and other restorative protocols monitor those cycles with serial transvaginal ultrasound, a series of vaginal ultrasound scans. The aim is to detect an overreaction early. The aim is also to support the cycle a woman already has, rather than replace it with a drug-driven one.

For women with PMOS / PCOS who do not ovulate regularly, a more basic question comes first. What hormonal and metabolic problems are preventing ovulation, and have they been identified and addressed? Cycle charting can show whether and how a woman ovulates. So can ultrasound grading of ovulation (sonographic ovulation classification) and hormone testing during follicle maturation monitoring. Many women with PMOS / PCOS who receive targeted metabolic and hormonal support conceive naturally. They do so without the high-dose drug path that carries OHSS risk.