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Background: In human oocytes, as in other mammalian ova, there is a significant variation in the pregnancy potential, with approximately 20% of oocyte-sperm meetings resulting in pregnancies. This frequency of successful fertilization decreases as the oocytes age. This low proportion of fruitful couplings appears to be influenced by changes in mitochondrial structure and function. In this study, we have examined mitochondrial biogenesis in both hamster (Mesocricetus auratus) and mouse (Mus musculus) ova as models for understanding the effects of aging on mitochondrial structure and energy production within the mammalian oocyte. Methodology/Principal Findings: Individual metaphase II oocytes from a total of 25 young and old mice and hamsters were collected from ovarian follicles after hormone stimulation and prepared for biochemical or structural analysis. Adenosine triphosphate levels and mitochondrial DNA number were determined within individual oocytes from young and old animals. In aged hamsters, oocyte adenosine triphosphate levels and mitochondrial DNA molecules were reduced 35.4% and 51.8%, respectively. Reductions of 38.4% and 44% in adenosine triphosphate and mitochondrial genomes, respectively, were also seen in aged mouse oocytes. Transmission electron microscopic (TEM) analysis showed that aged rodent oocytes had significant alterations in mitochondrial and cytoplasmic lamellae structure. Conclusions/Significance: In both mice and hamsters, decreased adenosine triphosphate in aged oocytes is correlated with a similar decrease in mtDNA molecules and number of mitochondria. Mitochondria in mice and hamsters undergo significant morphological change with aging including mitochondrial vacuolization, cristae alterations, and changes in cytoplasmic lamellae. [ABSTRACT FROM AUTHOR]

These studies investigated the role of substance P (SP) in the regulation of the hypothalamic-pituitary-ovarian axis in cynomolgus monkeys with normal menstrual cycles. Plasma concentrations of SP were determined in blood samples taken every morning in normally menstruating cynomolgus monkeys throughout the menstrual cycle. There was a significant decreasing linear trend of SP during the follicular phase (cycle day –13 to day 0) and a significant inverse relationship between SP plasma values and plasma 17β-estradiol (E[sub 2] ) values from day –13 to day 0 of the adjusted cycle. Correspondingly, SP area under the curve was significantly greater during the follicular phase than the luteal phase. In a second experiment, plasma concentrations of E[sub 2] , luteinizing hormone (LH), follicle-stimulating hormone (FSH) and progesterone and length of cycles were measured after five daily intragastric administrations (10 mg/kg) of an NK[sub 1] receptor (SP receptor) antagonist (RPR 100893; 10 mg/kg) initiated after serum E[sub 2] concentrations had exceeded 125 pg/ml. There was a statistically significant reduction in the amplitude (41% of control) and the area under the curve (37% of control) of the preovulatory LH surge. In addition, there was a reduction of the duration of the LH surge (3 ± 0.1 days in controls vs. 2.1 ± 0.2 days in treated animals). The present results show for the first time that there are significant variations in plasma levels of SP, with a strong negative correlation with serum levels of E[sub 2] during the follicular phase of the cynomolgus monkey, and that endogenous SP has a potentiating role in the interactive hypothalamo-anterior-pituitary mechanisms which lead to the preovulatory LH and FSH surges during the menstrual cycle in the monkey.Copyright © 2000 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

This study assessed the behavioural and psychological profiles of children conceived by in-vitro fertilization (IVF) who are now at school age. A total of 743 IVF children born at one institution and now of school age, over 4 years old, were surveyed with Achenbach questionnaires. Follow-up telephone interviews were conducted with non-responders. The results from the study group were compared to the questionnaire control group using one-tailed t-test with statistical significance set less than 0.05. There was an 84% overall response rate. Sixty-seven per cent returned questionnaires. An additional 17% completed a telephone interview. The study group had no statistically significant increase in the rate of behavioural or psychological problems compared with the control group. There were no statistically significant differences within the study group related to sex or to multiple gestation IVF births. This large group of school-age IVF children has normal psychological development with no identified adverse effect of their status as IVF children. Determining the role, if any, of IVF in the very small number of children with behavioural and psychological problems will require additional study. [ABSTRACT FROM AUTHOR]

The article discusses the scientific interest of reproductive biologist Robert Geoffrey Edwards and his works which resulted in the birth of Louise Brown, who was the first baby to undergo fertilization in vitro. Edwards discovered his interest in animal seeds after taking a course on agriculture and then pursued a study on eggs and sperm at the Institute of Animal Genetics in Edinburgh, Scotland. The author relates the advice imparted to him by Edwards regarding the insemination and transfer of oocyte in the event of its fertilization.