Assessment and hormonal treatment of the luteal phase of in vitro fertilization cycles.

Luteal phase lengths and hormonal profiles (progesterone, oestradiol-17 beta, beta HCG and prolactin) have been documented in 77 cases derived from a series of patients undergoing IVF. Nineteen pregnancies were generated during this series and 12 healthy infants have already been delivered. Luteal phase lengths were 14.5 +/- 0.5 days with 14.3% demonstrating mid-luteal progesterone levels of less than 31 nmols/l, considered to be low for successful conception. A random study of luteal support regimens comparing HCG or medroxyprogesterone acetate (MPA) with nil therapy was studied in a series of 44 consecutive embryo transfers during which 10 pregnancies were achieved. No difference was noted in the pregnancy rates for the 3 groups but the pregnancy outcome was better in those who had HCG support and this was more apparent in the overall series of 19 pregnancies. A significant luteotrophic effect was noted with HCG support regimens whilst MPA appeared to have a luteal suppressant action. Six pregnancies which aborted with blighted ova were derived from cycles in which the luteal phase progesterone levels were low raising the possibility that a poor hormonal environment may predispose to blighted ova.