C. Briton-Jones

Infertility, blood mercury concentrations and dietary seafood consumption: a case–control study

Objective To compare blood mercury concentrations of infertile couples with those of fertile couples in Hong Kong, and to examine the relationship between blood mercury concentrations and seafood consumption.

Vascular Endothelial Growth Factor in the Human Oviduct: Localization and Regulation of Messenger RNA Expression In Vivo

Abstract In this study, we examined the localization of vascular endothelial growth factor (VEGF) and the changes in VEGF mRNA expression in various regions of the oviduct in fertile women throughout the ovulatory cycle. Oviduct tissue was collected from 22 women undergoing laparoscopic tubal sterilization or hysterectomy for a benign gynecological condition. Oviduct sections were divided into isthmus, ampullary, and infundibular regions. Serial cross sections were analyzed for the presence of VEGF by specific immunohistochemical staining. The mucosal layer was isolated, and a semiquantitative reverse transcription polymerase chain reaction was performed. Immunohistochemical study revealed VEGF in the oviduct luminal epithelium, smooth muscle cells, and blood vessels within the oviduct. VEGF mRNA expression in oviduct was the highest during the periovulatory stage, and the expression in the ampullary and infundibular regions was higher than that in the isthmus. There was a significant positive correlation between serum FSH and LH concentrations and VEGF mRNA expression. There was no significant correlation between serum estradiol and progesterone concentrations and VEGF mRNA expression. These results suggest that VEGF in human oviduct may play an important role related the early reproductive events, which occur predominantly in the ampulla during the periovulatory phase when serum FSH and LH concentrations are high.

The effect of timing of embryonic progression on chromosomal abnormality

OBJECTIVE To evaluate the relationship between aneuploidy and timing of blastocyst formation. DESIGN Historical cohort study. SETTING Private IVF clinic. PATIENT(S) Ninety-four couples undergoing IVF treatment in combination with chromosomal screening of embryos. The mean maternal age was 39.2 years and average number of embryos per patient 5.3. INTERVENTION(S) A total of 530 embryos were biopsied on day 3 and underwent chromosome screening with microarray-based comparative genomic hybridization. MAIN OUTCOME MEASURE(S) Effect of day of embryo blastulation and morphologic grade on aneuploidy rate. RESULT(S) Day 5 morulas that progressed to blastocysts on day 6 were significantly less likely to be aneuploid (79.8%) than day 5 morulas that did not progress to blastocysts (92.9%). However, there was no significant difference in aneuploidy rates when embryos that became blastocysts on day 5 were directly compared with embryos that became blastocysts on day 6. CONCLUSION(S) Delayed blastulation is not associated with increased aneuploidy rates, but absence of blastulation is associated with increased aneuploidy. Therefore, we conclude that when choosing a morula for transfer on day 5, there may be a benefit in waiting an extra day for the possibility of blastulation to occur.

Regulation of human oviductin mRNA expression in vivo.

OBJECTIVE To examine changes in oviductin mRNA expression in oviductal mucosal tissue from fertile women throughout an ovulatory cycle. DESIGN Semiquantitative reverse-transcriptase-polymerase chain reaction (RT-PCR) analysis of oviductin mRNA. SETTING University-based obstetrics and gynecology department. SUBJECT(S) Twenty women undergoing laparoscopy for tubal sterilization or hysterectomy for uterine fibroids. INTERVENTION(S) The mucosal layer was isolated from the oviduct tissue, and semiquantitative RT-PCR was performed. MAIN OUTCOME MEASURE(S) The relationship between serum estradiol, luteinizing hormone, and progesterone concentrations and the expression of oviductin mRNA. RESULT(S) There was a significant positive correlation between serum estradiol and luteinizing hormone concentrations and oviductin mRNA expression. There was a significant inverse correlation between serum progesterone concentrations and oviductin mRNA expression. CONCLUSION(S) Little is known about the regulation of human oviductin. This study was the first to examine the relationship between oviductin mRNA expression and serum estradiol and luteinizing hormone and progesterone concentrations in fertile women. Estradiol and luteinizing hormone both have a stimulatory effect on oviductin mRNA in humans, however, it is difficult to determine whether the effects are independent of one another, as the luteinizing hormone surge is dependent on the estradiol increase. Progesterone shows a clear inhibitory effect on oviductin mRNA.

Variable Expression of Oviductin mRNA at Different Stages of Human Reproductive Cycle

AbstractPurpose: To examine the in vivo expression of oviductin mRNA at different stages of the human female reproductive cycle including pregnancy and after menopause. Methods: Oviducts were obtained from 25 women in normal menstrual cycle, 5 in early pregnancy, 5 undergoing postpartum sterilization, and 4 menopausal women. The oviductal mucosal tissue was isolated and oviductin mRNA was assessed using reverse-transriptase-polymerase chain reaction (RT-PCR); its correlation with various hormones was assessed. Results: Oviductin mRNA was detected throughout the menstrual cycle, highest in the periovulatory period. It continued to be expressed in early pregnancy but was absent in the postpartum period and after menopause. Conclusions: The production and function of oviductin at different stages of human reproductive cycle including pregnancy is not well known. Its highest expression at the time of ovulation is consistent with a supportive role in fertilization and early embryo development.

Human oviductin mRNA expression is not maintained in oviduct mucosal cell culture

OBJECTIVE To determine whether oviduct mucosal cell culture supports the continued production of oviductin, a putative embryotrophic protein. DESIGN Semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR) analysis of oviductin messenger RNA (mRNA) expression after oviduct mucosal cell culture. SETTING University-based obstetrics and gynecology department. PATIENT(S) Ten women undergoing laparoscopy for tubal sterilization or hysterectomy for uterine fibroids. INTERVENTION(S) The mucosal layer was isolated from the oviduct tissue and subjected to routine culture conditions; semiquantitative RT-PCR was performed. MAIN OUTCOME MEASURE(S) The relationship between duration of cell culture and expression of oviductin mRNA. RESULT(S) There was a significant reduction in oviductin mRNA expression after 3 days in culture, with a complete loss after 6 days in 70% of the samples and after 12 days in the remaining 30%. CONLCUSION(S): This is the first study to investigate whether oviductin mRNA continues to be expressed in cultured human oviduct mucosal cells. Our results suggest that oviduct mucosal cells lose their ability to produce oviductin after short-term culture. This method of culture does not appear to be appropriate for a coculture system reliant upon oviductal secretion of oviductin.

Ratio of mRNA expression of progesterone receptor isoforms AB is to B in human oviduct mucosal cells during the ovulatory cycle.

The ratio of the active progesterone receptor B isoform is higher in the ampullary region of the oviduct.Purpose: To examine mRNA expression of progesterone receptor isoforms AB and B in oviduct mucosal tissue during the ovulatory cycle and in the different functional regions of the human oviduct.Methods: The mucosal layer was isolated from human oviduct tissue and semi-quantitative RT-PCR for progesterone isoforms AB and B was performed. The RT-PCR results were verified by immunohistochemistry.Results: The isthmic region showed no mRNA expression of either progesterone receptor isoform while the relative ratio of the B isoform was significantly higher in the ampullary region compared to the fimbrial region. There was a significant increase in the ratio of PRB to PRAB in the ampullary region compared to the fimbrial region in all samples.Conclusions: We found an increase in the relative abundance of the progesterone receptor B isoform in the ampullary region which is the site of fertilization and early embryo cleavage. Our results indicate that progesterone responsive genes are more likely to be activated in the ampullary region of the oviduct due to the difference in PRAB to PRB ratio. Providing support for the hypothesis that progesterone may play a specific role in providing an appropriate environment for sperm capacitation, fertilization and early embryo cleavage.

Ultrastructural characterization of whole hydrosalpinx from infertile Chinese women

Hydrosalpinx (HSP) has been shown to be detrimental to the outcome of assisted reproduction, but little is known of its pathology. This prospective study examined and detailed ultrastructural characterization of HSP of infertile women presenting for assisted reproductive treatments. Both light and electron microscopies were used to characterize HSP. Hematoxylin and eosin staining of HSP showed areas without epithelial cell lining or with abnormalities such as flattening of the epithelial layer and exfoliation of epithelial cells with occasional normal columnar epithelial lining. HSP muscle fibers were atrophic and occasionally replaced by fibrous tissues, or separated by areas of severe edema. Inflammatory cells could be found in hydrosalpinx fluid (HF) in the lumen in areas with flattened to no epithelial cells, without epithelial lining, as well as in dilated blood vessels and/or lymph vessels. Scanning electron microscopy of the epithelial surface revealed epithelial denudation‐severe loss of both cilia and microvilli and stomata exuding globular bodies on eroded ampulla surfaces. Severe chronic inflammation and damage to the epithelial lining and musculature of Fallopian tubes and the presence of inflammatory cells provides an explanation for HF formation, and thus for the detrimental effects of HF on reproductive processes and IVF outcome.

The effects of follicular fluid and platelet-activating factor on motion characteristics of poor-quality cryopreserved human sperm.

Purpose: To evaluate the effects of follicular fluid and platelet-activating factor on sperm motion characteristics of cryopreserved oligospermic and normospermic samples.Methods: Sperm motion characteristics were evaluated prior to cryopreservation, immediately after thawing and following incubation in human tubal fluid, follicular fluid, or 1-μM platelet-activating factor cultures. Sixteen oligospermic samples and 20 normospermic samples were examined. Sperm motion characteristics were analyzed manually according to WHO criteria (1999) and also with an automated videomicrography system.Result(s): Incubation in follicular fluid increased overall motility and the percentage of sperm with fast progressive motility in normospermic but not oligospermic samples. Incubation with platelet-activating factor increased overall motility and the percentage of sperm showing nonprogressive motility in both oligospermic and normospermic samples.Conclusion(s): The stimulatory effects of culture in follicular fluid as seen in normospermic samples do not show a significant benefit in oligospermic cryopreserved samples. Platelet-activating factor and follicular fluid increase motility via different mechanisms. Incubation of oligospermic cryopreserved sperm with PAF increases the number of motile sperm, thereby enabling easier identification of viable sperm for intracytoplasmic sperm injection in samples with severe asthenozoospermia.

The Efficacy of Test Tube Warming Devices Used During Oocyte Retrieval for IVF

AbstractPurpose: To investigate whether commonly used test tube warming devices maintain a constant temperature in follicular fluid aspirates. Methods: By using a digital thermocouple, temperature was measured and comparisons were made between an analog dry block heater, a digital dry block heater, and a thermostatic test tube heater. Results: For small fluid volumes, temperature in the block heaters increased above 37°C after being in the block for over 2 min. The thermostatic heater maintained a constant temperature, but this was below the factory setting of 36.9°C. Temperature maintenance was influenced by fluid volume in each tube. Conclusions: One of the key factors in the handling of gametes and embryos is the maintenance of constant temperature. Test tube warming devices require verification of their ability to maintain fluid at the desired temperature. Temperature may vary with fluid volume and the type of test tube warming device used.