LUTEAL PHASE SUPPORT AND SEVERE OVARIAN HYPERSTIMULATION SYNDROME

The incidence and statistical associations of the ovarian hyperstimulation syndrome (OHSS) were studied in 304 egg retrievals with gonadotrophin-releasing hormone agonist suppression, gonadotrophin administration and follicular aspiration. In addition to preserving corpus luteum function, the luteal phase administration of human chorionic gonadotrophin (HCG) was associated with a higher incidence of severe OHSS than was supplementation with progesterone alone (12 versus 0%, P < 0.001). Severe OHSS occurred in 3.7% and 12% of retrievals without and with pregnancy respectively (P < 0.01). Stepwise logistic regression showed that the occurrence of moderate or severe OHSS was statistically predicted by the log of the serum oestradiol on the day the initial HCG was given (P < 0.0001), treatment with luteal phase HCG (P < 0.0003), and fetal number (P < 0.0079). In the late luteal phase of cycles without luteal HCG, the serum oestradiol concentration was one-tenth and the serum progesterone concentration was one-fifth of the luteal phase value with HCG support (P < 0.001). Without luteal phase HCG, oestradiol was two-fold higher (P < 0.001) and progesterone was 1.4-fold higher (P < 0.005) in pregnant than in non-pregnant women. With luteal phase HCG, oestradiol was 1.4-fold higher in pregnant than in nonpregnant women (P < 0.05), and progesterone was 1.7-fold higher (P < 0.001). Oestradiol upper limits of 4400 and 14 700 pmol/l (1200 and 4000 pg/ml) for cycles with and without luteal phase HCG respectively correspond to approximately 5% risk of moderate or severe OHSS with a singleton pregnancy under these conditions.