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“Proof-of-principle” that cell replacement therapy works for neurodegeneration has been reported, but only using donor cells collected from fetal brain tissue obtained from surgical terminations of pregnancy. Surgical terminations of pregnancy represent an increasingly limited supply of donor cells due to the tendency towards performing medical termination in much of Europe. This imposes a severe constraint on further experimental and clinical cell transplantation research. Therefore, we explore here the feasibility of using medical termination tissue as a donor source. Products of conception were retrieved from surgical terminations over the last 7 years and from medical terminations over the last 2.5 years. The number of collections that yielded fetal tissue, viable brain tissue, and identifiable brain regions (ganglionic eminence, ventral mesencephalon, and neocortex) were recorded. We studied cell viability, cell physiological properties, and differentiation potential both in vitro and following transplantation into the central nervous system of rodent models of neurodegenerative disease. Within equivalent periods, we were able to collect substantially greater numbers of fetal remains from medical than from surgical terminations of pregnancy, and the medical terminations yielded a much higher proportion of identifiable and dissectible brain tissue. Furthermore, we demonstrate that harvested cells retain the capacity to differentiate into neurons with characteristics appropriate to the region from which they are dissected. We show that, contrary to widespread assumption, medical termination of pregnancy-derived fetal brain cells represent a feasible and more readily available source of human fetal tissue for experimental cell transplantation with the potential for use in future clinical trials in human neurodegenerative disease.

This paper is based on a Cochrane review published in The Cochrane Library, issue 3, 2002 (see www.CochraneLibrary.net for information) with permission from The Cochrane Collaboration and Update Software. Cochrane reviews are regularly updated as new evidence emerges and in response to comments and criticisms, and The Cochrane Library should be consulted for the most recent version of the review.

The Fallopian tube has been reported to undergo cyclical changes. However, many studies of tubal ultrastructure have either examined one segment of the tube only or studied animal oviducts. The aim of this study was to document in detail the combined morphological and ultrastructural features of the epithelial lining along the length of the tube in women at different stages of the menstrual cycle. We report an increase in the proportion of ciliated cells along the tube, being highest in the fimbriae, but no substantial difference between the follicular and luteal phases of the menstrual cycle. In the late follicular phase, fragments of cytoplasmic and cellular material were seen in the isthmic lumen but not in the outer tubal segments. Similarly, surface domes and secretory granules were more prominent in the mid-tube and ampullary sections than in the fimbriae. This surface activity was followed by relative quiescence in the early/mid luteal phase with reversion to a more active surface but with little secretory activity in the late luteal phase. These findings along the Fallopian tube substantiate the concept of functional differentiation between the different segments and necessitate further studies to determine its clinical relevance.

Cyclical ultrastructural changes in the endometrium and Fallopian tube have been reported previously but in different subjects. The aim of this study is to compare cyclical changes in endometrial gland and tubal (isthmic, mid-tube, ampulla, and fimbria) epithelia in the same subjects with a view to identifying any similarities or differences which may have clinical implications for assisted reproduction treatment. Endometrial and Fallopian tube samples were obtained from women undergoing hysterectomy and salpingectomy. We report similar epithelial surface changes taking place in the endometrial glandular and endosalpingeal epithelia with the exception of the fimbriae. Secretions within endometrial gland lumen and the isthmus increase throughout the late follicular phase and before ovulation, then dissipate in these two regions simultaneously in the early/mid luteal phase. Similarly, in the late follicular and pre-ovulatory phases, the process of granule secretion is similar in the glandular epithelium, isthmus and ampulla. In the fimbriae, no comparable activity is noted during these phases of the menstrual cycle. The differences reflect the functional differentiation between these regions. Equally, the observed similarities highlight the need for further comparative studies to determine the role of these secretions in early embryonic development and their clinical relevance.

Oestrogen and progesterone are known to require their corresponding steroid receptors to manifest structural and functional effects in the Fallopian tube, uterus and other target organs. This study compares cyclical variations of these receptors in the uterus and in different segments of the Fallopian tube in the same subjects using an immunocytochemical technique. The results show that in the Fallopian tube, isthmic and ampullary epithelial and stromal oestrogen receptors increased in the follicular phase to a peak at mid cycle and then declined in the late luteal phase. The intensity of immunostaining of oestrogen receptors was less in the Fallopian tube than in endometrial glandular epithelium. The fimbrial end demonstrated an opposite pattern of staining to other segments of the tube. Progesterone receptor immunostaining was more intense than that for oestrogen receptors in the follicular phase, and, whereas it disappeared completely from the endometrial glandular epithelium in the late luteal phase, positive staining was clearly visualized in the tubal epithelium and stroma and endometrial stroma at this stage of the menstrual cycle. These differences in the steroid receptor content may reflect the changing and different functional roles of these regions and may have important implications on human reproduction.

Several treatments for infertility have been promoted with only little supporting objective data demonstrating their therapeutic value. The choice of an assisted reproductive technique depends on a balance between numerous factors. Seldom is the choice absolute as in patients with tubal block. There is conflicting evidence on the efficacy of simpler methods such as ovarian stimulation with or without artificial insemination and the available data suggest that the more invasive methods such as gamete intra-Fallopian transfer or in-vitro fertilization are more effective in the treatment of couples with unexplained infertility. Equally, there is no conclusive evidence that pregnancy rates with any of the invasive techniques are superior to any others. However, a higher implantation rate following tubal embryo transfers is observed in many studies. This review presents a critical assessment of the effectiveness of assisted reproductive techniques.

The value of pelvic ultrasound early in the investigation of infertile women has not been fully evaluated. Eighty-eight patients attending the infertility clinic for the first time had an ultrasound scan before their diagnostic laparoscopy. Normal ultrasound scans had a negative predictive value of 67 per cent whereas abnormal scans gave a positive predictive value of 88 per cent. Preoperative diagnosis of gynaecological pathology using a simple and non-invasive technique allows pre-operative counselling of the therapeutic options and proceeding with the definitive treatment at the time of laparoscopy if the scan findings are confirmed. Pre-operative scans also provide baseline measurements of fibromyomata or endometriotic cysts before commencing medical treatment for these conditions. Pelvic ultrasound is important in the investigation and management of subfertile women.