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A retrospective study of 34 sequential gamete intraFallopian transfer (GIFT) procedures suggested a significant effect on
pregnancy rates associated with the different laparoscopic light sources, with a pregnancy rate of 50% in 22 cycles using
a halogen light source and 9% in 12 cycles using a xenon light source. Other explanatory variables were ex...
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... however none was observed. The two light sources were then investigated further using spectral irradiance (Bentham Instruments Ltd, Reading, UK) and it was noted that the spectral irradiance for the xenon light source included more radiation in the ultraviolet (UV) and infrared areas than the halogen light source (Figure 1). The laboratory requirements for successful culture of gam- etes and embryos are well known and many factors responsible for damage, including temperature variations, pH variations, toxic substances, culture media constituents and contaminated air have been identified and reviewed (Bavister, 1995;Cohen et al., 1997). ...
Citations
... Sun leaves are thicker than shaded leaves ) and LMA is commonly affected by growth irradiance. Plants grown in the field have more light which may lead to increased chloroplast surface area, chlorophyll and Rubisco content and consequently greater photosynthetic capacity (Nishio et al., 1993;Evans et al., 1999). When measuring different sets of genotypes to determine variation in electron transport rate and leaf structure, it is important to take into account such G ? E interaction, because genetic potential for J and LMA measured in the glasshouse could be underestimated and as mentioned before, more measurements in the field are required to understand plant physiology (Slattery et al., 2013). ...
The world population is rising, placing increasing
demands on food production. One way to contribute to food
security is by improving yields of staple crops like wheat. Yield
can be calculated from the product of plant biomass and harvest
index (the ratio of grain yield to above ground biomass). Since
harvest index of wheat has already reached its maximum biological
limit in some environments, attention is now focused on
increasing crop biomass. Efficient interception of
photosynthetically active radiation and effective photosynthetic
sugar production underpin yield, however, little breeding has
been done for photosynthetic performance. Exploiting existing
genetic variation for important photosynthetic traits such as
photosynthetic capacity (Pc) and photosynthetic efficiency (Peff)
will help to improve wheat yield. CO2 assimilation rate, which is
a commonly measured parameter for assessing photosynthetic
performance, is found to vary across wheat genotypes. Two
additionally important parameters are Rubisco activity (Vcmax)
and electron transport rate (J). There is much less information
reported regarding genetic variation of these two latter
parameters because measurements of CO2 response curves with gas
exchange used to derive Vcmax and J are slow and unsuitable for
rapid screening of many genotypes in the field. The two main
objectives of this project were firstly, to find out if there is
genetic variation for these important photosynthetic traits in
wheat, and secondly, to develop a rapid method for screening
photosynthetic and leaf attributes in different wheat genotypes.
To deal with variable leaf temperatures in the field and
accurately estimate Vcmax and J, improved values for the
temperature dependence of several Rubisco kinetic parameters were
needed. These temperature-dependencies were derived from
measurements made under controlled conditions. A method for
rapidly estimating variation in Pc components Vcmax and J and in
other photosynthetic traits was developed based on calibration of
leaf reflectance spectra against photosynthetic parameters
derived using conventional gas exchange, morphological (leaf mass
per unit area, LMA) and chemical (nitrogen and chlorophyll per
unit area) measurements of 76 wheat genotypes screened in several
different environments. When observed data were compared against
predictions from reflectance spectra, correlation coefficients
(R2 values) of 0.62 for Vcmax25, 0.71 (J), 0.89 (LMA) and 0.93
(Narea), were obtained. Reflectance spectra from an additional
458 elite and landrace wheat genotypes were measured to further
assess variation in photosynthetic traits. There were significant
differences between wheat genotypes in Vcmax25 per unit N, which
is a good measure of Peff. Environment presented interaction with
genotypes for Pc and Peff when measurements performed in
glasshouse & field or in Australia & Mexico were compared. In
future, linking genotypic variation for photosynthetic traits to
DNA-based genetic markers will permit even faster selection of
genotypes in breeding. Reflectance spectra should be a good tool
to accelerate identification and selection of wheat genotypes and
detection of important genomic regions for photosynthetic
capacity and efficiency in wheat.
... A number of studies have shown how some environmental factors can have a detrimental effect on oocytes and embryos such as exposure to light, [43,44] temperature, [45] polyvinyl chloride, [46] polychlorinated biphenyls, [47] and other environmental conditions. [45,48] The importance of keeping embryo temperature close to 37°C and O 2 and CO 2 concentrations under specific ranges is well known, [48,49] and a number of technological devices have been designed to avoid their fluctuations in oocytes and embryos during their manipulation and storage. ...
... Many studies have also shown the detrimental effect of environmental factors such as light, heat, polyvinyl chloride and polychlorinated biphenyls on oocytes and embryos (Cohen et al., 1997;Evans et al., 1999;Hunter et al., 1988;Pocar et al., 2001;Rocha et al., 1998;Smith, 1993). The importance of keeping embryos close to 37°C and between specific oxygen and carbon dioxide concentration ranges is well known (Bavister, 1995;Cohen et al., 1997). ...
The aim of this retrospective study was to investigate factors affecting clinical pregnancy rates, especially age and duration of embryo transfer, in IVF/intracytoplasmic sperm injection cycles (1313 embryo transfers). Overall clinical pregnancy rate was 30.0% (n=394). Clinical pregnancy rates were found to be 31.6% for the <44 s interval, 25.9% for the 45-59 s interval and 23.6% for the > or = 60 s interval (P=0.020). In the <35 year age group, clinical pregnancy rates were 35.1%, 29.9% and 30.6%, and in the > or = 35 year age group, they were 26.9%, 21.0% and 13.4% (P=0.013), respectively. According to logistic regression analyses, the odds of failed pregnancy increased by 1.61 times [95% confidence interval (CI) 1.07-2.41] for embryo transfer durations longer than 60 s and odds ratios of a failed pregnancy were 1.53 (95% CI 1.18-1.99) in the > or = 35 year age group, 1.49 (95% CI 1.05-2.12) for fewer than five oocytes and 3.38 (95% CI 2.10-5.43) for fewer than two transferred embryos. In conclusion, to increase the likelihood of a successful pregnancy in women over 35 years of age, the duration of embryo transfer must be kept below 60 s. The number of oocytes obtained and the number of transferred embryos also play a role in the success of pregnancy.
... It has been shown how some conditions can interfere with embryo implantation, mainly by a negative effect on endometrial receptivity (endometrial damage, uterine contractions, presence of blood or bacteria, embryo misplacement) (Fanchin et al., 1998;Goudas et al., 1998;Lesny et al., 1998;Coroleu et al., 2002;Marikiniti et al., 2003). On the other hand, a number of studies have shown how some environmental factors can have a detrimental effect on oocytes and embryos such as exposure to light (Smith et al., 1993;Evans et al., 1999), temperature (Rocha et al., 1998), polyvinyl chloride (Hunter et al., 1988), polychlorinated biphenils (Pocar et al., 2001), and other environmental conditions (Cohen et al., 1997;Rocha et al., 1998). The importance of keeping embryo temperature close to 378C and O 2 and CO 2 concentrations under specific ranges is well known (Bavister, 1995;Cohen et al., 1997), and a number of technological devices have been designed to avoid their fluctuations in oocytes and embryos during their manipulation and storage. ...
To ascertain the influence of the duration of the 'interval loading-discharging embryos' (ILDE) on the results of embryo transfer.
The population under study consisted of 450 consecutive fresh embryo transfers. ILDE was measured in all transfers. Pregnancy and implantation rates were analyzed.
Conceptional cycles had a lower (mean +/- SD) ILDE than non conceptional cycles (53.5 +/- 43.6 s vs 63.7 +/- 49.3). When only easy transfers--defined as those not requiring cervical tenaculum--were considered, similar differences were observed. The following pregnancy rates were obtained according ILDE duration: 38.9% (ILDE < 30 s), 33.2% (ILDE 31-60), 31.6% (ILDE 61-120) and 19.1% (ILDE > 120) (P < 0.05). When only easy transfers were considered, similar results were obtained: 40.0%, 33.3%, 32.0% and 19.4%, respectively. Similar results were observed regarding implantation rates regarding the whole population (21.2%, 15.4%, 15.9% and 9.4%, respectively; P < 0.01) as well as when only easy transfers were considered.
ILDE duration is a prognostic factor of pregnancy rate and of implantation rate in IVF. The longer the ILDE duration, the lower the pregnancy and implantation rates. The decrease in pregnancy and implantation rates is gradual until an ILDE of 120 s, and decreases sharply afterwards. It is recommended to speed up the embryo transfer process, wherever possible. ILDE > 120 s carries a poor prognosis and should, when possible, be avoided.
... Originally, GIFT was performed by laparotomy and currently is performed almost exclusively by laparoscopy (Rombauts et al., 1997). Although most laparoscopic GIFT is actually done under general anaesthesia (Evans et al., 1999), some authors (Milki et al., 1992;Milki and Tazuke, 1997) report a significant cost containment and scheduling flexibility using local anaesthesia. ...
BACKGROUND: Gamete intra-Fallopian transfer (GIFT) is a successful technique for infertile women, and is performed almost
exclusively by laparoscopy under general anaesthesia. METHODS: We performed a prospective randomized study of 67 infertile
patients to assess the efficacy of minilaparoscopic GIFT under conscious sedation/local anaesthesia (group A) compared with
general anaesthesia (group B). Operative and discharge times and pregnancy outcome were evaluated in both groups. RESULTS:
Operative time was similar in both groups. The rate of patients discharged 2 h after surgery was significantly higher in group
A. The necessity for postoperative analgesics was significantly higher in group B. No significant differences were noted between
the two study groups in terms of pregnancy outcome. CONCLUSIONS: Conscious sedation and local anaesthesia will allow us to
perform an outpatient minilaparoscopic GIFT without the need for general anaesthesia. The simplicity of the method, and the
quicker discharge time in comparison with general anaesthesia, offer a detectable benefit for patients.
Maintaining consistent and reliably high success rates is a daily challenge for every IVF laboratory. This step-by-step guide is an essential aid in navigating the complex maze of physical, chemical, biological, and logistic parameters that underpin successful gamete and embryo culture: temperature, pH, osmolality, gas supplies, air quality, light exposure, infections, managing supplies, personnel, as well as overall quality control. Numerous real-life troubleshooting case reports are presented, identifying all aspects necessary for troubleshooting. Process maps and flow charts accompanying each chapter offer a logical and systematic approach to problem solving in the laboratory. This is an essential resource for scientists in assisted reproductive technology and specialists in reproductive biology and medicine, helping IVF clinics to achieve the dream of every infertile couple: the birth of a healthy child.
Maintaining consistent and reliably high success rates is a daily challenge for every IVF laboratory. This step-by-step guide is an essential aid in navigating the complex maze of physical, chemical, biological, and logistic parameters that underpin successful gamete and embryo culture: temperature, pH, osmolality, gas supplies, air quality, light exposure, infections, managing supplies, personnel, as well as overall quality control. Numerous real-life troubleshooting case reports are presented, identifying all aspects necessary for troubleshooting. Process maps and flow charts accompanying each chapter offer a logical and systematic approach to problem solving in the laboratory. This is an essential resource for scientists in assisted reproductive technology and specialists in reproductive biology and medicine, helping IVF clinics to achieve the dream of every infertile couple: the birth of a healthy child.
The outcome and costs of testicular sperm extraction under outpatient local analgesia or general anaesthesia were compared
in men with non-obstructive azoospermia. Nineteen consecutive patients were allocated to receive general anaesthesia, while
the subsequent 21 consecutive patients received outpatient analgesia in the form of i.v. midazolam sedation, lignocaine spray,
scrotal infiltration with local anaesthetic and spermatic cord block. Blood pressure, pulse rate and respiratory rate were
determined. Sedation and testicular pain were assessed by subjective scoring. Both groups showed haemodynamic stability with
little alteration in blood pressure, pulse rate and oxygen saturation. Toxic symptoms of local anaesthetic were not encountered
in the outpatient group. No relationship was found between testicular size and the duration of the operation. The median postoperative
pain intensity, sedation scores and analgesic requirements were significantly less in the outpatient group (P < 0.05). These advantages led to a shorter recovery time (P < 0.0001), 3-fold cheaper care and greater patient satisfaction (P < 0.0001) in the outpatient group.
A Trust Analysis of a Gestational Carrier's Right to Abortion proposes that the relationship involving a gestational carrier, the intended parents and fetus is analogous to a trustee relationship in which the gestational carrier owes a fiduciary duty to the other parties. Due to this higher standard of care, the authors argue that the gestational carrier's right to abort can, and should, be restricted. Additionally, the article also provides an extensive review of the medical procedures involved in in vitro fertilization of a gestational carrier and examines and refutes various arguments proposed to support the unrestricted right to abortion.
