Ovarian Hyperstimulation Syndrome (443)

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This procedure describes the general clinical procedures that need to be undertaken within the Assisted Conception Service (ACS), Glasgow Royal Infirmary (GRI).

OHSS is self-limiting and usually resolves spontaneously within several days. However, it may persist for longer particularly in those women receiving assisted conception treatment. Mild OHSS is common – it occurs in up to 33% of IVF treatment cycles. Moderate to severe OHSS is rare (occurs in 3 to 8% of IVF treatment cycles) but is life threatening. The clinical course is, however, a continuum of scope and severity.

Clinicians should be aware and women informed that pregnancies complicated by OHSS may be at increased risk of pre-eclampsia and preterm delivery. Those most at risk of suffering from OHSS are young women (<30 years of age) with a low BMI undergoing ovarian hyperstimulation treatment. Other predisposing factors include:

• PCOS
• The presence of multiple follicles/oocytes
• Treatment with hCG (to mature oocytes during ovarian hyperstimulation)
• Previous OHSS
• Pregnancy

In all cases, the Assisted Conception Service team at GRI must be:

• informed of the diagnosis using the proforma 
• involved in clinical decisions and supervision of continuing care.