ABSTRACT
RESEARCH QUESTION: Does splitting the human chorionic gonadotrophin (HCG) support in IVF cycles triggered by a gonadotrophin-releasing hormone agonist result in a better progesterone profile? DESIGN: Randomized controlled three-arm study, performed at the Fertility Clinic, Odense University Hospital, Denmark. Patients with 12-25 follicles ≥12 mm were randomized into three groups: Group 1 - ovulation triggered with 6500 IU HCG; Group 2 - ovulation triggered with 0.5 mg GnRH agonist, followed by 1500 IU HCG on the day of oocyte retrieval (OCR); and Group 3 - ovulation triggered with 0.5 mg GnRH agonist, followed by 1000 IU HCG on the day of OCR and 500 IU HCG on OCRâ¯+â¯5. All groups received 180 mg vaginal progesterone. Progesterone concentrations were analysed in eight blood samples from each patient. RESULTS: Sixty-nine patients completed the study. Baseline and laboratory data were comparable. Progesterone concentration peaked on OCRâ¯+â¯4 in Groups 1 and 2, and peaked on OCRâ¯+â¯6 in Group 3. On OCRâ¯+â¯6, the progesterone concentration in Group 2 was significantly lower compared with Groups 1 and 3 (Pâ¯=â¯0.003 and P < 0.001, respectively). On OCRâ¯+â¯8, the progesterone concentration in Group 3 was significantly higher compared with the other groups (both P<0.001). Progesterone concentrations were significantly higher in Group 3 from OCRâ¯+â¯6 until OCRâ¯+â¯14 compared with the other groups (all P ≤ 0.003). Four patients developed ovarian hyperstimulation syndrome in Group 3. CONCLUSION: Sequential HCG support after a GnRH agonist trigger provides a better progesterone concentration in the luteal phase.