Cytomorphometric analysis of vaginal cells during normal cycle, under oral contraceptive therapy or in-vitro fertilization stimulation protocol

A cytomorphometric analysis of superficial vaginal cells inwomen in three groups of different types of hormonal concentrationwas made. There were 15 women in each group. Group I was studiedduring a natural cycle, group II under oral contraceptive therapyand group III during an in-vitro fertilization (IVF) stimulationprotocol. Morphometric parameters were measured on an imageanalyser. The area, perimeter and several form factors weremeasured separately for nuclei and cytoplasm. The nucleus:cytoplasmicratio was also determined. The cytoplasmic area was significantlyreduced in group II and was associated with a statisticallysignificant reduction of the nuclear area. The nucleus:cytoplasmicratio appeared significantly increased in group II and reducedin group III. Low oestradiol impregnation obtained with an oralminidosed contraceptive interfered with vaginal cell maturation.High oestradiol concentrations obtained during IVF protocolsinduced marked nuclear pycnosis but did not induce supra-physiologicalcell enlargement. Maximal cell size is genetically regulatedaccording to Driesch's law of volume invariance and hormonalover-stimulation has no effect on cell size. The nucleus:cytoplasmicratio appears to be a powerful parameter reflecting the oppositeeffects of hormones on cell compartments.     

Granulosa cell metabolism and the assessment of oocyte quality in IVF

The progesterone production of the granulosa cells of the cumulus– oocyte complex correlates very well with the cleavagepotential of embryos in an IVF system. The method is simpleand can be easily performed by any laboratory associated withIVF. Furthermore, high intratubal progesterone levels in theimmediate post-ovulatory period are probably important in prolongingthe intra-ampullary residence of the oocyte or embryo untilthe uterine endometnum is optimal for implantation.     

Prospective randomized study of D-Trp6-LHRH versus buserelin in long desensitization protocols for medically assisted conception cycles

In a prospective, controlled, randomized study where two differentagonists were used, we compared three different long desensitizationprotocols for induction of multiple follicular growth in medicallyassisted conception cycles. In protocol A, 30 patients wereinjected with buserelin twice a day for 15 days prior to ovarianstimulation until human chorionic gonadotrophin (HCG) administration.In protocol B, 30 patients were injected with a single doseof long acting Triptorelin (3.75mg) 15 days before the ovarianstimulation onset. In protocol C, 30 patients were injectedwith the long acting Triptorelin 4 weeks before ovarian stimulationfollowed by daily administration of 0.1 mg of the same agonistuntil HCG injection. There was no difference in the ovarianresponse to exogenous gonadotrophin stimulation, except forthe presence of premature luteinization in two patients in groupB. A significantly higher number of mature oocytes was collectedfrom patients with protocol A; however, the fertilization andcleavage rate demonstrated no significant difference among thethree groups of patients. The ongoing pregnancy rate and theimplanation rate per treatment cycle were very similar in thethree study groups. When the convenience, cost and side-effectsfor the patient are being considered, protocol B should be selectedas the first choice when the agonist is utilized for the purposeof inducing pituitary desensitization before and during ovarianstimulation.     

Who will conceive with IVF?

When considering the chances of establishing a healthy ongoing pregnancy after in vitro fertilization (IVF), the cause of infertility plays a relatively minor role. In recent years, there has been a shift from determining the diagnosis to the individual prognosis for a given patient. A number of prognostic factors were identified, which enabled clinicians to appropriately counsel patients. Patient-determined factors are of crucial importance and some are amenable to intervention such as lifestyle and nutritional advice. However, the attention of clinicians remains on seeking adjuvant therapeutic interventions designed to improve the outcomes of IVF treatment. In this article, the patient-determined factors underlying the individual chance of conceiving and the more commonly prescribed empirical medical therapies prescribed to enhance outcomes are reviewed. It is concluded that greater attention to optimizing the health of the couple before starting IVF treatment may be more beneficial than adjuvant medical therapies during treatment.     

精子形态变化对体外受精率的影响

目的:通过对ICSI和IVF受精率的统计,比较精子形态中的精子正常形态率、头部畸形率、畸形精子指数(TZI)和精子畸形指数(SDI)对受精结果的影响。方法:用Krger's严格标准法分别计算每组样本的精子正常形态率、头部畸形率、TZI和SDI值,与受精率进行比较。结果:①IVF组和ICSI组的受精率,与精子正常形态率、头部畸形率、TZI、SDI均无相关性。②IVF组和ICSI组中SDI>1.6和SDI<1.6的受精率、优质胚胎率和临床妊娠率差异均无统计学意义(P>0.05)。③IVF组和ICSI组中精子正常形态率≤15%与精子正常形态率>15%的二组间受精率、优质胚胎率和临床妊娠率的差异均无统计学意义(P>0.05)。结论:精子形态在体外受精时对受精率无影响,不能用精子形态来直接评价体外受精的结果。     

Incidence of cancer in children born after in-vitro fertilization

Evaluation of the long-term health of children born using in-vitro fertilization (IVF) provides important information to clinicians and consumers. Until very recently, there have been no published data on the incidence of cancer in children conceived as a result of IVF, despite a number of case reports of neuroblastoma in children conceived using fertility drugs. This study used a record-linkage cohort design to investigate the incidence of cancer in children born after IVF. The study included all conceptions using assisted reproductive technologies between 1979 and 1995 at two clinics in Victoria, Australia that resulted in a live birth. Data on births were linked with a population-based cancer registry to determine the number of cases of cancer that occurred. The standardized incidence ratio (SIR) was calculated by comparing the observed number of cases to the expected number of cases. The final cohort included 5249 births. The median length of follow-up was 3 years, 9 months (range 0-15 years). In all, 4.33 cases of cancer were expected and six were observed, giving a SIR of 1.39 (95% CI 0.62-3.09). This study found that children conceived using IVF and related procedures did not have a significantly increased incidence of cancer in comparison to the general population.     

The frequency of chromosome anomalies in human preimplantation embryos after in-vitro fertilization

Previous studies have reported chromosome aberrations in humanpre-embryos after in-vitro fertilization (IVF). Although thereason for these abnormalities is not clear, there is evidencethat they can arise during gametogenesis, fertilization or cleavage.The present study has examined further the incidence of chromosomeabnormalities in human pre-embryos after IVF, using oocytesrecovered from normal volunteer women and from women undergoinginfertility treatment in an embryo-replacement programme. Chromosomepreparations were performed for 75 pre-embryos. Of these 35(47%) gave at least one metaphase in which analysis was possible.The overall incidence of abnormal pre-embryos was 40% (14/35).The absolute frequency of aberrations was 9% for trisomies,3% for polyploidies, 26% for structural anomalies and 3% forhypodiploidies. Five pre-embryos were found to be mosaics, threeof which had each one trisomic metaphase. In five of the pre-embryosmultiple anomalies were found. In 13 of the 14 abnormal pre-embryosthe aberrations were found in only one metaphase. The presentstudy demonstrates that trisomic mosaicism may not be a rareevent in human pre-embryos. Further evidence is provided thatmitotic non-disjunction is important for the production of aberrationsin human pre-embryos     

'Vanishing embryo syndrome' in IVF/ICSI

BACKGROUND: In a Danish population-based cohort study assessing the risk of cerebral palsy in children born after IVF, we made some interesting observations regarding 'vanishing co-embryos'. METHODS and RESULTS: All live-born children born in Denmark from 1 January 1995 to 31 December 2000 were included in this analysis. The children conceived by IVF/ICSI (9444) were identified through the IVF Register, the children conceived without IVF/ICSI (395 025) were identified through The Danish Medical Birth Register. Main outcome measure was the incidence of cerebral palsy. Within the IVF/ICSI children we found indications of an increased risk of cerebral palsy in those children resulting from pregnancies, where the number of embryos transferred was higher than the number of children born. CONCLUSIONS: The association between vanishing embryo syndrome and incidence of cerebral palsy following IVF requires further investigation in larger, adequately powered, studies.     

Reducing the time of sperm-oocyte interaction in human in-vitro fertilization improves the implantation rate

Human oocyte development was evaluated after a reduced timeexposure to spermatozoa in vitro. A total of 119 patients wereassigned to two study groups in a randomized prospective studyin which each patient‘s oocytes were exposed to spermatozoafor either 1 h (group 1 – 58 patients) or the standard16 h incubation period (group 2 – 61 patients). The fertilizationrate obtained in group 1 was higher than in group 2 (285/393,73%, and 272/410, 66% respectively), suggesting that the spermatozoa-oocyteinteraction occurs within 1 h. This was confirmed in a studyin vitro using fluorescently labelled spermatozoa and normaloocyte-cumulus complexes. Spermatozoa enter the cumulus complexwithin 15 min, traverse the cumulus layer within 3 h, and firstappear in the oocyte cortex at 4 h post-insemination. The incidenceof polyspermy was higher in oocytes exposed to spermatozoa for16 h (3%) than for 1 h (1%). There was no difference in thecleavage rate or morphological characteristics of embryos fromboth study groups. However, when evaluating the timing of embryodevelopment, group 1 generated a significantly higher percentageof four to five cell embryos when compared to group 2 (55 versus39%; P < 0.001), documented at 40 h post-insemination. Theimplantation and pregnancy rates for group 1 were 11 and 28%,while the corresponding rates for group 2 were 8 and 15%. Thissuggests that a reduced exposure of oocyte to spermatozoa favoursembryo viability, possibly due to a decrease in potential damagefrom sperm metabolic waste products.     

Increased seminal plasma lead levels adversely affect the fertility potential of sperm in IVF

BACKGROUND: Lead remains in high levels in the environment and is known to reduce fertility in animal models, but a direct link between lead exposures and human infertility has not yet been established. METHODS: In a prospective, double-blind study of the metal ion levels and sperm function, semen was obtained from partners of 140 consecutive women undergoing their first IVF cycle. Lead in seminal plasma was determined by atomic absorption spectroscopy. Motile sperm populations were assessed for surface receptors for mannose binding, and the ability to undergo premature ('spontaneous'), and free mannose-induced acrosome reactions. Fertile donor (n = 9) sperm were exposed to exogenous lead during capacitating incubations and then assessed for mannose receptor expression and acrosome loss. RESULTS: Lead levels were negatively correlated with IVF rates. Lead levels were negatively correlated to two of the three sperm function biomarkers (mannose receptors, mannose-induced acrosome reactions). Lead levels positively correlated with the spontaneous acrosome reaction. These findings were mimicked by in-vitro exposure of fertile donor sperm to lead. CONCLUSIONS: Multiple sperm parameters are affected as lead levels rise. Increased lead levels may contribute to the production of unexplained male infertility.