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PubMed2004

[Twin pregnancies and their outcome at the Department of Obstetrics and Gynecology, Institute of Mother and Child in Warsaw, in the period of 1993-2000].

OBJECTIVE: The aim of this study was to analyse the course of twin pregnancies delivered at the Department of Obstetrics and Gynaecology, Institute of Mother and Child in Warsaw, from 1993 to 2000. MATERIALS AND METHODS: The medical documentation of women with twin pregnancy was looked into. Such parameters as mode of conception, maternal age and parity were taken into account. The data concerning the duration of pregnancy, mode of delivery, birth weight and condition of newly born infants were retrospectively reviewed. RESULTS: There a total of 232 (1.46%) twin pregnancies out of 15,869 births. A gradual increase in absolute number of twin deliveries and a relative increase of multiple pregnancies due to the use of assisted reproduction techniques was observed. The tendency to end twin pregnancies by caesarean section was detected. Although the perinatal care improved over the years, a small decrease of mean gestational age at delivery was observed. No significant difference in neonatal outcome in relation to the mode of delivery in researched material was noticed. CONCLUSIONS: The number of twin pregnancies due to the use of assisted reproduction techniques is on the increase. A percentage of women delivering for the first time has risen among women with twin pregnancy. Twin pregnancies are often ended by caesarean section and the frequency of caesarean sections has increased over time.

Academies and Institutes↗
PubMedDate not supplied

Sperm aneuploidy in infertile men.

A recent line of research has shown that infertile male patients produce cytogenetically abnormal spermatozoa, despite a normal somatic karyotype, as a result of an altered intra-testicular environment that affects negatively the mechanisms controlling chromosome segregation during cell division. The rate of aneuploid spermatozoa production is significantly higher in patients with abnormal sperm parameters compared with those of normozoospermic subjects or infertile patients with normal sperm parameters. All chromosomes are subject to aneuploidy, although at a different rate; the heterochromosomes are more often altered than are the autosomes. A negative correlation has been reported to exist between aneuploidy and the main sperm parameters, suggesting that greater testicular damage is associated with a greater chance of chromosome malsegregation events. Abnormally-shaped spermatozoa are more likely to have chromosome abnormalities, particularly those with an enlarged head. More studies are necessary, however, to evaluate whether other types of sperm head abnormalities are also associated with an abnormal sperm chromosome complement. The possibility of retrieving testicular or epididymal spermatozoa in patients with azoospermia and using them in assisted reproduction techniques has prompted the evaluation of their chromosomal status. Studies have shown that testicular and epididymal spermatozoa have a greater rate of aneuploidy compared with that of ejaculated spermatozoa. Some authors have also shown that patients with non-obstructive azoospermia have a significantly higher sperm aneuploidy rate compared with that of patients with obstructive azoospermia. Sperm aneuploidy seems to have a negative impact on assisted reproduction technique outcome. Although it does not affect the fertilization rate, an elevated sperm aneuploidy rate is associated with a greater rate of pregnancy failure. Nevertheless, some patients with elevated sperm aneuploidy rate can still achieve a pregnancy, but with an increased risk of generating an aneuploid offspring. Thus, sperm aneuploidy evaluation is recommended in infertile patients with abnormal semen parameters, particularly if they undergo IVF programmes.

Aneuploidy↗
PubMed1996

Beyond recanalizing proximal tube occlusion: the argument for further diagnosis and classification.

Proximal tube occlusion (PTO) accounts for 20% of tubal factor cases. The classification into nodular (salpingitis isthmica nodosa or endometriosis), non-nodular (true fibrotic occlusion) and so-called pseudo occlusion (detritus, polyps, hypoplastic tubes) is essential. Using falloposcopy, PTO that is already diagnosed by laparoscopy and hysterosalpingography (HSG) can be confirmed or bypassed (false PTO); patients with false PTO were placed on a temporary waiting period. Nodular and pseudo occlusion patients were pre-treated with gonadotrophin-releasing hormone analogue (GnRH-a) for at least 6 weeks to shrink the underlying pathology, after which tubal re-catheterization was performed. In a prospective study starting in July 1993, 53 patients prediagnosed as having PTO were examined by falloposcopy. Three of these patients had non-nodular occlusion and were directed to microsurgical repair (conservative treatment not possible). A total of 19 cases revealed patent tubes with healthy mucosa and no underlying pathology (false PTO). Of the remaining 31 patients, 18 were classified as nodular and 13 as pseudo occlusion. In all of these patients at least one tube was patent after GnRH-a treatment. After a 6 month period, 37% of the false PTO patients achieved a spontaneous pregnancy (6% per cycle). The spontaneous pregnancy rate in the true PTO group was significantly lower (10% per patient, 1.6% per month; P < 0.05). Using assisted reproduction techniques, in particular gamete intra-Fallopian transfer (GIFT), as a subsequent treatment for the true PTO group, a pregnancy rate of 50% per cycle was achieved. A retrospective analysis of our entire PTO population (n = 109) showed a spontaneous pregnancy rate after achieving tubal patency (using falloposcopy and GnRH-a) that was dramatically low (1.8%), with no difference between the nodular and pseudo groups. The chance for pregnancy can be enhanced significantly (P < 0.001) using assisted reproduction techniques (GIFT) following tubal re-catheterization and GnRH-a treatment.

Buserelin↗
PubMed2002

The place of gonadotrophin-releasing hormone antagonists in reproductive medicine.

Gonadotrophin-releasing hormone (GnRH) antagonists have recently been introduced into clinical practice. They appear to offer a promising alternative to the long-established GnRH agonist regimens for prevention of a premature LH surge during ovarian stimulation for assisted reproductive techniques. Clinical outcomes achieved with antagonists are comparable with those of a long GnRH agonist protocol, while treatment times and gonadotrophin requirements are reduced and safety is improved. In particular, the antagonists appear to be associated with a lower risk of ovarian hyperstimulation syndrome (OHSS) than do agonists. Patient surveys suggest a preference for antagonist over agonist treatment cycles. These benefits suggest that GnRH antagonists have the potential to replace agonists as the treatment of choice in ovarian stimulation for assisted reproductive techniques. Two agents, cetrorelix and ganirelix, are currently in clinical use. Cetrorelix is available in single- and multiple-dose formulations, offering increased flexibility compared with ganirelix.

Amino Acid Sequence↗
PubMed2005

Assisted reproductive practice: religious perspectives.

It is important to those who practise reproductive techniques to learn about different religious perspectives related to reproductive health problems. Religious groups are active in influencing the public regarding bioethical positions, and this is particularly evident with issues concerning procreation, abortion and infertility therapy. The Jewish attitude towards procreation is derived from the first commandment of God to Adam to 'Be fruitful and multiply'. Judaism allows the practice of all techniques of assisted reproduction when the oocyte and spermatozoon originate from the wife and husband respectively. The attitude toward reproductive practice varies among Christian groups. While assisted reproduction is not accepted by the Vatican, it may be practised by Protestant, Anglican and other denominations. According to traditional Christian views, beginning at conception, the embryo has moral status as a human being, and thus most assisted reproductive technologies are forbidden. According to Islam, the procedures of IVF and embryo transfer are acceptable, although they can be performed only for husband and wife. Developments in science and technology and corresponding clinical applications raise new religious questions, often without clear answers. The role of theology in bioethics is integral to clarify perceived attitudes toward these developments for different religious communities. This paper presents the attitude of monotheistic religions to therapeutic procedures, such as IVF-embryo transfer, spermatozoa, oocytes, embryo donation, cryopreservation of genetic material, surrogacy, posthumous reproduction, gender preselection, reproductive and therapeutic cloning.

Attitude↗
PubMed1983

A catheterization technique for reproduction of a human atherosclerotic lumen within the dog coronary artery in vivo.

Reproduction of a human atherosclerotic lumen within the arterial lumen of an intact animal would facilitate angiographic and hemodynamic studies of stenoses. Accordingly, a male silicone rubber cast of a human atherosclerotic lumen was obtained from a cadaver artery, and a thin-walled replicate arterial phantom was constructed from the cast by use of a rapidly polymerizing liquid plastic. The casting properties of both materials were such that the topography of the arterial lumen was duplicated precisely in the phantom with 20 x microscopic detail preserved. The phantom was coated with a banzalkonium-heparin solution and introduced over a guidewire into an epicardial segment of a coronary lumen of the dog. Similarly, a larger phantom was placed within the dog femoral artery either directly via an arteriotomy or indirectly via a catheterization technique. Since the plastic material used to make a phantom had the same radiographic density of tissue, the angiographic appearance of an intra-arterial phantom was that of a human stenosis.

Animals↗
PubMed2002

First trimester screening with free beta-hCG, PAPP-A and nuchal translucency in pregnancies conceived with assisted reproduction.

OBJECTIVE: To evaluate the effect of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) on free beta-human chorionic gonadotrophin (beta-hCG), pregnancy-associated plasma protein A (PAPP-A) and nuchal translucency (NT). METHODS: First trimester maternal dried whole blood specimens from 74 singleton pregnancies (32 by IVF and 42 by ICSI) and 30 twin pregnancies (16 by IVF and 14 by ICSI) in which conception was achieved with assisted reproduction techniques were matched with five controls resulting in 370 singleton controls and 150 twin controls. NT was measured using the Fetal Medicine Foundation protocol. Free beta-hCG, PAPP-A and NT levels were compared between the IVF and control groups and between the ICSI and control groups using the Mann-Whitney U test. RESULTS: In singleton pregnancies, the only significant difference was a 21% (95% CI: -35%--7%) reduction in PAPP-A in IVF cases. In twin pregnancies, the only significant difference was a 12% (95% CI: -34%--3%) reduction in NT in IVF cases. In singleton pregnancies, the false-positive rate for Down syndrome screening was 1.4% and 1.9% greater for the IVF and ICSI groups, respectively, compared to controls for a general screening population. CONCLUSIONS: Patients undergoing assisted reproduction techniques should be counseled about the possibility of increased false-positive rates. Larger studies are needed to confirm this observation and to develop appropriate adjustment factors to reduce false-positive rates.

Biomarkers↗
PubMed2005

Somatic chromosomal abnormalities in infertile men and women.

Infertility--the inability to achieve conception or sustain a pregnancy through to live birth--is very common and affects about 15% of couples. While chromosomal or genetic abnormalities associated with azoospermia, severe oligozoospermia or primary ovarian failure were of no importance for reproduction prior to the era of in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI), advances in assisted reproductive techniques (ART) now enable many infertile couples to have children. These developments have raised the question of the genetic consequences of ICSI: concerns of the potential harm of the invasive procedure and concerns about the genetic risk. The infertile male and female definitely have an increased risk to carry a chromosomal abnormality. Detection of such an abnormality is of fundamental importance for the diagnosis of infertility, the following treatment, the evaluation of the risk for the future child and the appropriate management of the pregnancy to be obtained. Therefore, cytogenetic screening of both partners is mandatory prior to any type of ART. The present review is based on several surveys on male and female infertility and analyzes the types and frequencies of the different reported chromosome abnormalities according to the type of impairment of spermatogenesis and the type of treatment planned or performed. With regard to assisted reproductive techniques (especially ICSI) the main types of chromosomal abnormalities are discussed and their potential risks for ICSI. If available, reported cases of performed ICSI and its outcome are presented. The detection of an abnormal karyotype should lead to comprehensive genetic counselling, which should include all well-known information about the individual type of anomaly, its clinical relevance, its possible inheritance, the genetic risk of unbalanced offspring, and the possibilities of prenatal diagnosis. Only this proceeding allows at-risk couples to make an informed decision regarding whether or not to proceed with ART. These decisions can be made only when both partners have clearly understood the genetic risks and possible consequences when ART is used.

Chromosome Aberrations↗
PubMed2004

FSH: urinary and recombinant.

Infertility affects approximately 10-15% of couples. To enhance the chances of conception, assisted reproductive techniques (ART) have been improved and, in the last 5 years, thousands of babies have been delivered after IVF or ICSI procedures. To obtain an appropriate and controlled ovarian hyperstimulation (COH), clinicians have introduced many drug protocols based on GnRH agonists or antagonists for pituitary down-regulation and FSH or HMG for ovarian stimulation. Currently FSH is the most common drug used for ovulation induction. It is a glycosylated protein with a molecular weight of 28000-30000Da, normally secreted by the anterior pituitary gland. The recombinant preparations of follicle stimulation hormone (r-FSH) are characterized by a higher level of purity, reduced batch to batch variability and no risk of infection. The purpose of this review was to establish the efficacy of different trials based on the use of r-FSH and urinary FSH (u-FSH) comparing published data from randomised studies on the ovulation induction for assisted reproductive techniques. Unfortunately, we did not find any paper with sufficient power to detect a clinically significant difference in pregnancy rates, however, recent meta-analysis among homogeneous trials indicates that the use of r-FSH is to be preferred to u-FSH because more oocytes were collected in cycles with better embryo quality and with more pregnancies. Recombinant FSH has a higher cost per ampoule than urinary FSH, but also a higher effectiveness. A recent cost-effectiveness analysis on follitropin alfa compared to urinary FSH-HP, using a Markov model, confirmed other previous studies that, considering the ongoing pregnancies beyond 12 weeks gestation, r-FSH is the most effective therapy for ovulation induction in ART.

Female↗
PubMed2007

Aphasia: an early uncommon complication of ovarian stimulation without ovarian hyperstimulation syndrome.

Thromboembolic disease associated with assisted reproductive techniques is extremely rare. A 21-year-old woman with primary infertility underwent an ovulation induction cycle with luteal long protocol. Twenty-four hours following oocyte retrieval, the patient complained of difficulty in speaking. On neurological examination, mild disorientation, motor aphasia, and right-sided hypoesthesia were noted. Brain computed tomography scanning without contrast revealed left parietal lob infarct. Brain magnetic resonance imaging (MRI), MRI angiography (MRA) and perfusion MRI demonstrated an occlusion of the posterior division of the left middle cerebral artery (MCA). Physical, ultrasound examinations and laboratory test evaluation failed to reveal ovarian hyperstimulation syndrome. Except for ovarian stimulation, no additional risk factors for stroke were shown. Following anticoagulation and speech therapy, the patient recovered completely within eight months. One year after the left MCA thrombosis, she conceived spontaneously and had an uncomplicated vaginal delivery of a live male infant weighing 2900 g at 38 weeks gestation. This case supports that ovulation induction and assisted reproductive techniques may be a newly recognized cause of cerebral infarction in otherwise healthy women.

Adult↗
PubMed2006

[Heterotopic pregnancy].

The heterotopic pregnancy is a combination of an intra-uterine and extra-uterine pregnancy, at the same time. The spontaneous heterotopic pregnancy is a rare illness with an estimated frequency below one per 20,000 and one per 30,000. The first case was reported in France by Duverney in 1708 during an autopsy. The frequency of this pregnancy has increased with the implementation of assisted reproduction techniques. This paper is the report of a case of spontaneous heterotopic pregnancy seen at the Angeles Mexico Hospital. A 32 year old woman, gravida 1; dilatation and curettage was performed on 13th February because of a blighted ovum, a lot of products of conception were obtained. The patient was discharged the next day only with analgesics. She returns to the emergency room on February 16th with hypovolemic shock and acute abdomen. A normocitic normocromic anemia was found on the hematic biometry, the transvaginal ultrasound reported amount of blood in the cul-de-sac, echogenic adnexal mass, suggesting a gestational sac with embryo. An emergency laparotomy was used to perform a left cornual resection; the findings were 600 cc of hemoperitoneum and a left ruptured ectopic pregnancy. She had an uneventful postoperative course, and was discharged 72 hours later without complications. Heterotopic pregnancy is a rare illness and must always be considered for the increase in pregnancy related with assisted reproduction techniques, although, it should be considered in a spontaneous pregnancy too.

Adult↗
PubMed2005

Single, transcervical insemination using frozen-thawed semen in the Greyhound: a case series study.

Transcervical insemination (TCI) has generated recent interest as an assisted reproductive technique in the dog. A case series study was performed to determine if TCI using frozen-thawed semen was a viable technique to offer in a general veterinary practice setting. Over a period exceeding 28 months, 137 Greyhound bitches were presented for assisted breeding. A single, timed insemination using a rigid cystoscope to aid in transcervical deposition of a frozen-thawed semen dose was given within 72 h after the behaviorally estrual bitch had a > 4 ng/mL serum progesterone concentration and estrus-categorized vaginal cytology. Litter size, pregnancy and whelping rate were collected; their association to semen center and stud dog were quantified. Of the 137 bitches, 117 were bred for one cycle and 20 were bred for two or more cycles, giving a total of 161 single, timed inseminations. Pregnancy rate was 89.4%, with 141 (87.5%) whelping. Litter size was 6.9+/-2.7 (mean+/-S.D.) pups. Semen center (P=0.84) and stud (P=0.79) had no effect on pregnancy. These results were quite favorable when compared to prior TCI studies, and are possibly due to the use of a single breed (i.e., Greyhound) with good fertility. This study supported the application of TCI, in Greyhounds, as a successful and viable service to offer in private practice. Additionally, these results have value in their use for benchmarking future breed-specific and TCI research. Serendipitously, the apparent fecundity results obtained in this observational study suggests a possible greater appreciation be given to breed composition and choice in assisted reproductive technique studies.

Animals↗
PubMed1994

New indication of testis biopsy for azoospermia: a clinical study in Japanese patients.

Because of the progress made with assisted reproductive techniques, we decided to clarify the indication for testis biopsy in Japanese azoospermic patients. A total of 88 azoospermic patients were recruited with testis histologies obtained by bilateral biopsy. Testicular histology was evaluated using Johnsen's score count. Patients with at least 1 testis containing sperm were assigned to the active spermatogenesis group. Patients whose testes had no sperm were assigned to the hypospermatogenesis group. Differences in terms of the clinical data between the 2 groups were analyzed. Clinical data consisted of past history, physical examination and hormone concentrations. The unpaired t test was generally used to examine the statistical significance of any differences between the 2 groups. 1) There were significant differences between the 2 groups in the levels of serum testosterone and luteinizing hormone. 2) There were markedly significant differences between the 2 groups in terms of testis volume and the concentration of serum follicle-stimulating hormone (FSH). 3) The smallest testis volume and the highest serum FSH value in the active spermatogenesis group were 7 ml and 32.7 mlU/ml (normal range 2.9-8.2), respectively. In conclusion, although the presence or absence of active spermatogenesis can be accurately predicted by measuring the testis volume and serum FSH, testis biopsy should be carried out in patients with a testis volume greater than 7 ml or a serum FSH less than 4 times normal when the use of assisted reproductive techniques are planned.

Adult↗
PubMed1999

Ascites and liver test abnormalities during severe ovarian hyperstimulation syndrome.

OBJECTIVE: Severe ovarian hyperstimulation syndrome is an uncommon cause of ascites that is being increasingly recognized because of the high number of women undergoing assisted reproductive techniques, mainly in vitro fertilization. This prospective study investigates the clinical and biochemical characteristics of a large series of patients with this syndrome and ascites, including renal and electrolyte abnormalities, activity of neurohormonal systems participating in the regulation of extracellular fluid volume, and liver function tests. METHODS: This was a prospective longitudinal study including 50 consecutive patients with ascites due to severe ovarian hyperstimulation syndrome. Renal function, serum electrolytes, body weight, mean arterial pressure, pulse rate, plasma renin activity, plasma concentration of aldosterone, norepinephrine, antidiuretic hormone and atrial natriuretic peptide, and standard liver function tests were measured during the syndrome and 4-5 wk after recovery. A sample of ascitic fluid was obtained from eight patients for protein measurement and cell count. RESULTS: At diagnosis, patients had ascites associated with low urinary sodium excretion, oliguria, and hyponatremia. They had also markedly low arterial pressure and increased pulse rate in association with marked activation of vasoconstrictor and antinatriuretic factors. The ascitic fluid was characterized by a high protein concentration, low leukocyte count, and relatively high number of red blood cells. Fifteen (30%) patients had abnormal liver tests characterized by mild to moderate increases in AST (mean 103 +/- 17.1 IU/L) and ALT (76 +/- 8.3 IU/L), which were associated in some cases with increases in gamma-glutamyl transpeptidase or alkaline phosphatase. All abnormalities reverted to normal after the resolution of the syndrome. CONCLUSIONS: With the increasing use of assisted reproductive techniques, physicians should be aware of severe ovarian hyperstimulation syndrome as a cause of ascites. The syndrome is associated with sodium retention, hyponatremia, arterial hypotension, and marked activation of vasoconstrictor and antinatriuretic systems. In one third of patients, liver tests abnormalities are present.

Adult↗
PubMed2001

Heparin and Ca2+-free medium can enhance release of bull sperm attached to oviductal epithelial cell monolayers.

The success of assisted reproductive techniques, such as IVF, could be enhanced by being able to select the most competent spermatozoa in a sample. Attachment and subsequent release of spermatozoa from oviductal epithelial cells (OEC) could provide populations of functionally superior spermatozoa for use in these protocols. The objective of the present study was to investigate the ability of heparin and Ca2+-free medium to induce spermatozoa release from bovine OEC. Epithelial cells were grown to confluence in 24-well plates and pooled frozen bull semen was added to a final concentration of 1 x 10(6) spermatozoa/well. Spermatozoa were allowed to bind to OEC for 2 h. Medium with unbound spermatozoa was removed and replaced by Sperm-TALP, only (control), with heparin (5, 10, or 15 IU/mL), or Ca2+-free with 2 mM EGTA. Treatments were left on sperm-OEC co-cultures for 0.5, 1, 2, 3, or 5 h. At each time, the media were recovered and spermatozoa from each treatment were counted and evaluated for acrosome integrity and motility. The total number of spermatozoa attached to OEC after 2 h of co-culture was considered 100%. Spermatozoa release is expressed as percentage of the total number of sperm cells bound to OEC after 2 h of co-culture. Data were analyzed by ANOVA and results are expressed as mean +/- SEM from three independent replicates. Beginning at 0.5 h, more sperm cells (P < 0.05) were released from OEC in the heparin groups (10 and 15 IU/mL, 77.3 +/- 6.2% and 84.0 +/- 6.2%, respectively) as compared to the control (46.4 +/- 6.2%). The Ca2+-free medium also induced spermatozoa release when compared with the control, but the effect was not significant until 3 h (38.2 +/- 1.9% vs 59.5 +/- 6.9%; P < 0.05). The percentage of acrosome reacted spermatozoa was not affected by heparin treatment. Heparin at 10 IU/mL increased (P < 0.05) the percentage of motile spermatozoa, whereas Ca2+-free medium caused the opposite effect at 0.5 h after addition of treatments. We conclude that both heparin and Ca2+-free medium are able to promote spermatozoa displacement from OEC attachment. Based on motility and acrosome status data, we predict that released sperm cells may be used for IVF and other assisted reproductive techniques.

Animals↗
PubMed1999

Loss of livestock breeding efficiency due to uncompensable sperm nuclear defects.

An important goal of modern analyses of semen is to elucidate the molecular traits of mammalian sperm chromatin structural abnormalities, defined here as 'uncompensable', that lead to abnormalities in fertility, pronuclear formation, early embryo quality and pregnancy outcome. Sperm with uncompensable nuclear abnormalities are able to fertilize oocytes both in vivo and in vitro; however, due to the uncompensable trait(s), the embryo development may be abnormal. Uncompensable nuclear traits can be experimentally induced in bull sperm by a mild thermal insult to the testis. Sperm nuclear morphology abnormalities seen in ejaculates 11-days post stress are likely related to molecular changes in chromatin observed 3-days post stress by the flow cytometric sperm chromatin structure assay (SCSA). The SCSA measures the susceptibility of sperm nuclear DNA to denaturation in situ. This susceptibility has been correlated with the presence of DNA strand breaks that may be derived in part by oxidative stress and possibly by a unique, abortive apoptotic mechanism. The extent of DNA denaturation is not significantly related to the level of disulfide bonding between the chromatin protamines. The use of human sperm with uncompensable nuclear traits for artificial reproductive techniques is also discussed. The goal of this research is to remove from semen doses those sperm with uncompensable nuclear traits and thereby increase male fertility potential.

Animals↗
PubMed2002

Protocols, practices, and the reproduction of technique in molecular biology.

Protocols are one of the main organizational resources in molecular biology. They are written instructions that specify ingredients, equipment, and sequences of steps for making technical preparations. Some protocols are published in widely used manuals, while others are hand-written variants used by particular laboratories and individual technicians. It is widely understood, both in molecular biology and in social studies of science, that protocols do not describe exactly what practitioners do in the laboratory workplace. In social studies of science, the difference between protocols and the actual practices of doing them often is used to set up ironic contrasts between 'messy' laboratory practices and the appearance of technical order. Alternatively, in ethnomethodological studies of work, the difference is examined as a constitutive feature, both of the lived-work of doing technical projects, and of the administrative work of regulating and evaluating such projects. The present article takes its point of departure from ethnomethodology, and begins with a discussion of local problems with performing molecular biology protocols on specific occasions. The discussion then moves to particular cases in criminal law in which defense attorneys cross-examine forensic technicians and lab administrators. In these interrogations, the distinction between protocols and actual practices animates the dialogue and becomes consequential for judgments in the case at hand. The article concludes with a discussion of administrative science: the work of treating protocols and paper trails as proxies for actual 'scientific' practices.

Expert Testimony↗
PubMed1995

An evaluation of the effect of anesthetic technique on reproductive success after laparoscopic pronuclear stage transfer. Propofol/nitrous oxide versus isoflurane/nitrous oxide.

BACKGROUND: Laparoscopic pronuclear stage transfer (PROST) is the preferred method of embryo transfer after in vitro fertilization in many infertility programs. There are scant data to recommend the use or avoidance of any particular anesthetic agent for use in women undergoing this procedure. The authors hypothesized that propofol would be an ideal anesthetic for laparoscopic PROST because of its characteristic favorable recovery profile that includes minimal sedation and a low incidence of postoperative nausea and vomiting. The purpose of the study was to compare propofol and isoflurance with respect to postanesthetic recovery and pregnancy outcomes after laparoscopic PROST. METHODS: One hundred twelve women scheduled for laparoscopic PROST were randomized to receive either propofol/nitrous oxide or isoflurane/nitrous oxide for maintenance of anesthesia. RESULTS: Visual analog scale scores for sedation were lower in the propofol group than in the isoflurance group at all measurements between 30 min and 3 h after surgery. More women experienced emesis and were given an antiemetic during recovery in the isoflurance group than in the propofol group. However, the percentage of pregnancies with evidence of fetal cardiac activity was 54% in the isoflurane group compared with only 30% in the propofol group (P = 0.023). Also, the ongoing pregnancy rate was greater in the isoflurane group than in the propofol group (54% vs. 29%, P = 0.014). CONCLUSIONS: Propofol/nitrous oxide anesthesia was associated with lower clinical and ongoing pregnancy rates compared with isoflurane/nitrous oxide anesthesia.

Adult↗