EARLY FOLLICULAR RISE OF SERUM PROGESTERONE CONCENTRATION IN RESPONSETO A FLARE-UP EFFECT OF GONADOTROPIN-RELEASING-HORMONE AGONIST IMPAIRS FOLLICULAR RECRUITMENT FOR IN-VITRO FERTILIZATION

A retrospective study of 150 cycles of in-vitro fertilization (IVF) wa s undertaken to determine the impact of elevated serum progesterone in the early follicular phase of IVF cycles utilizing gonadotrophin-rele asing hormone agonist (GnRHa) initiated in the follicular phase. A tot al of 127 patients identified as being at risk for poor response to st imulation were treated with a flare-up protocol of GnRHa combined with high dose follicle stimulating hormone (FSH). Patients were excluded for severe male factor requiring micromanipulation. Patients were stim ulated with GnRHa beginning on cycle day 2, and high dose FSH beginnin g on cycle day 3. Some 85% of the cycles exhibited a rise of serum pro gesterone to a peak concentration of >1.0 ng/ml (range, 1.2-4.2 ng/ml) during cycle days 2-6. When compared to cycles,vith no demonstrable p rogesterone rise, cycles with a rise were associated with a significan tly decreased ovarian response: more ampoules of gonadotrophin were re quired (mean 26.8 versus 22.6, P < 0.05), lower peak oestradiol concen tration was reached (mean 774 pg/ml versus 1030; P < 0.05), and fewer mature oocytes were harvested (mean 4.6 versus 7.5; P < 0.01). Among t he different pregnancy outcomes (clinical pregnancy, no pregnancy, ong oing pregnancy, and miscarriage), there were no significant difference s detected in the early follicular progesterone concentrations as meas ured by peak progesterone, progesterone area under the curve (days 2-6 ), and day of peak progesterone. The follicular phase initiation of Gn RHa can result in significant elevations of serum progesterone in the early follicular phase, which may impair follicular recruitment and ov erall ovarian response.