Die Lutealphase nach Follikelpunktion

A short luteal phase in cycles stimulated with clomiphene and human menopausal gonadotropin for in vitro fertilization

Of 70 cycles stimulated with clomiphene and human menopausal gonadotropin (hMG) for an in vitro fertilization-embryo transfer (IVF-ET) program, a short luteal phase of 11 days or less was found in 18. In this group the mean estradiol and progesterone levels were elevated in the early luteal phase. Despite the elevated initial values, progesterone levels fell rapidly at the mid luteal phase as a sign of premature luteolysis. The mean total amount of gonadotropin administered and the mean number of follicles punctured and of oocytes recovered did not show any significant difference between the groups of normal and short luteal phases. The present findings support the theory that hyperestrogenism in the early luteal phase may initiate the premature luteolysis observed in clomiphene-menopausal gonadotropin-stimulated cycles.

Progesterone and luteinizing hormone profiles in heifers used as oocyte donors

Progesterone (P(4)) and luteinizing hormone (LH) profiles were analyzed throughout the estrous cycle in 11 superovulated heifers that had follicular oocytes aspirated at different times after standing heat. It was found that high P(4) during estrus was incompatible with normal LH release, oocyte maturation and subsequent in vitro fertilizing capability. However, an LH peak was not a prerequisite for initiation of meiosis, since both metaphase I (MI) and metaphase II (MII) stages were observed in animals without an LH surge. Following follicular aspiration, the progesterone levels and the length of luteal phase were similar to those of superovulated animals that had no follicular intervention. We concluded that aspiration per se does not interfere with normal corpora lutea (CL) development in heifers when aspiration occurs after the LH surge.