A semi-quantitative and non-invasive method for scoring embryos obtained after in-vitro fertilization (IVF) has been defined, aiming at selection of embryos before transfer and at prognostic evaluation of IVF trials. Grading of embryos observed on the inverted microscope was essentially based on the amount of anucleate fragments expelled during early cleavage and on developmental speed. Embryos endowed with a high score were more often associated with pregnancy and in particular with the occurrence of multiple pregnancy. No difference was observed between scores attributed to embryos related to ongoing, aborted or chemical pregnancies. Average embryonic scores corresponding to double and triple transfers differed significantly in failures as well as pregnancies. The better quality of embryos replaced in triple transfers was also apparent from the significantly higher implantation rate per embryo observed in this group. From our results, five criteria including clinical data and embryonic scores can be derived for defining a high risk of multiple pregnancy prior to transfer. It might be warranted to replace only two embryos when these conditions are fulfilled.
Among 297 couples who underwent 587 oocyte collection procedures, 95 (16%) total fertilization failures (FF) were observed. This frequency is similar in couples with either normal or only mildly deficient spermatozoa (16.2 and 13.7% respectively) but is almost doubled in cases of moderately and severely defective sperm (26.5%). However, this latter group accounts for only 19% of FF events. The fertilization rate per oocyte (FR) follows an inverse trend. FR was correlated with the final (i.e. after swim-up) sperm count and with initial and final motility of the sperm sample. If the final count and motility were less than 2 x 10(6)/ml and 40% respectively, the FF frequency in the group with partner's spermatozoa was significantly higher and FR significantly lower. FR was inversely correlated with the number of oocytes recovered but FF was found significantly more frequently only when fewer than three eggs were retrieved. No correlation was found between FF and either female causes of infertility, age or dosage of stimulation treatment. However, in the group with donor spermatozoa the FR was significantly lower amongst tubal, endocrinopathic and endometriotic patients (67.6, 67.2 and 56.6 respectively versus 79.7% in harvests from idiopathic cases). FR was decreased and FF increased when ovulation induction resulted from a spontaneous LH peak supplemented with human chorionic gonadotropin (HCG), as compared to induction by HCG alone. In the group using normal or mildly defective spermatozoa, if FF occurs at the first attempt, the frequency of recurrence in further trials is high (29%) and the probability of pregnancy after completed trials is low (12.5%).(ABSTRACT TRUNCATED AT 250 WORDS)
Fetal growth, reproductive capacity, and parasitemia were studied in three groups of BALB/c mice: pregnant and chronically infected with Trypanosoma cruzi, non pregnant but similarly infected, and pregnant but noninfected. The pregnant mice were killed on day 17 of pregnancy. Comparisons of the two pregnant groups showed significant differences in fetal weights and x 18 magnified ossification lengths of radius and cubitus, whereas placental weights were not modified. The results indicate that intrauterine growth retardation occurs during chronic marine T. cruzi infection. No difference was noted between the reproductive capacities of the two pregnant groups. Parasitemias were similar in infected pregnant and control groups. Mice of all groups survived infection until killing. Pregnancy, therefore, does not influence chronic murine T. cruzi infection. Parasites were never found in fetal blood, indicating a very low, if any, frequency of transplacental transmission of parasite during the chronic phase of infection.
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