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C Callan

Publications and source records attributed to C Callan.

9 recordsLinked to original sources
PubMed1996

The predictive value of an initial serum beta human chorionic gonadotropin level for pregnancy outcome following in vitro fertilization.

PURPOSE: Our purpose was to assess the predictive value for pregnancy outcome of an initial serum quantitative beta-hCG measurement obtained 11 or 12 days after embryo transfer in an in vitro fertilization program. METHODS: A prospective, descriptive study of 153 pregnancies achieved via in vitro fertilization-embryo transfer was performed. Initial beta-hCG levels and subsequent pregnancy outcomes were compared. RESULTS: The overall mean initial beta-hCG level was 91 +/- 85.8 mIU/ml for normal (singleton, multiple-gestation) pregnancies and 29 +/- 24.9 mIU/ml for abnormal (miscarriage, ectopic) pregnancies (P < 0.01; power, > 80%). While 93.9% of patients with initial beta-hCG levels > or = 42 mIU/ml had normal pregnancies, 56.4% of those with initial levels < 42 mIU/ml experienced abnormal outcomes. With 42 mIU/ml as the cutoff level for predicting a normal pregnancy, this screening test yielded a sensitivity of 79.3% and a specificity of 83.8%. CONCLUSIONS: Initial serum beta-hCG levels obtained 11 or 12 days after embryo transfer may be predictive of pregnancy outcome in an in vitro fertilization program.

Adult↗
PubMed1995

A comparative prospective study using matched samples to determine the influence of subnormal hypo-osmotic test scores of spermatozoa on subsequent fertilization and pregnancy rates following in-vitro fertilization.

The achievement of pregnancies in vivo is rare in couples where the male partner has defective sperm membranes as shown by hypo-osmotic swelling (HOS) test scores of < 50%. However, there have been mixed reports on the value of the HOS test in predicting outcome following invitro fertilization; some studies suggest reduced fertilization rates and others find little, if any, predictability of decreased fertilization. The assumption has been made that fertilization rates are proportional to pregnancy rates; however, this may not necessarily be true since defective spermatozoa could lead to a less viable pre-embryo and therefore a decreased viable pregnancy rate. We performed a comparative prospective study using matched controls to evaluate fertilization rates and to determine subsequent pregnancy rates. The mean HOS scores were 70.0 and 36.7% respectively, with mean motile sperm concentrations of 35.7 and 34.0 x 10(6)/ml in 27 matched pairs. There was no difference in the mean number of oocytes retrieved, fertilization rates or number of embryos transferred between the two groups by HOS score. The clinical and viable pregnancy rates and implantation rates were 25.9, 18.5 and 9.9% for normal versus 3.7, 3.7 and 1.1% for subnormal groups. These data suggest that low HOS scores may be associated with the formation of defective embryos, leading to low pregnancy rates but normal fertilization rates.

Female↗
PubMed1995

Inhalation toxicity study of a haloalkene degradant of sevoflurane, Compound A (PIFE), in Sprague-Dawley rats.

BACKGROUND: Under certain circumstances in the clinical setting, contact of the anesthetic sevoflurane with a CO2 absorbent (e.g., soda lime, Baralyme) leads to the formation of a degradant designated as pentafluoroisopropenyl fluoromethyl ether (PIFE; Compound A). Previous studies have shown that the kidney is the primary target organ for toxicity in the rat. This study was designed to determine the impact of PIFE on rat renal histology correlated with functional changes. The findings are discussed in terms of probable mechanism of action and relevance to humans. METHODS: Male and female Sprague-Dawley rats were exposed to 0, 30, 61, 114, or 202 ppm PIFE for a single 3-h period via nose-only inhalation. Rats were observed daily for behavioral changes or external physical signs of toxicity (i.e., lacrimation, dyspnea, piloerection, etc.) and body weights were recorded at 6, 4, and 1 day preexposure and 1, 3, 7, and 13 days postexposure. Animals were evaluated for hematologic, clinical chemistry and/or urinalysis changes immediately postexposure and/or at 1, 4, and 14 days postexposure. Rats were killed, subjected to a macroscopic postmortem examination, and evaluated for histopathologic changes in all major tissues and organs at 1, 4, and 14 days postexposure. RESULTS: Labored breathing was observed in 3 of the 20 and 2 of the 20 rats in the 114 ppm and 202 ppm groups, respectively, during the 3-h exposure period. No significant reductions in body weight gain were noted during the 2-week study period. Clinical chemistry evaluations revealed increases in blood urea nitrogen and creatinine 1 day postexposure in males and females exposed to 202 ppm PIFE. Changes in urinary glucose, protein and N-acetyl-beta-glucoaminidase/creatinine were evident one day postexposure in males and females exposed to 202 ppm and in males exposed to 114 ppm PIFE. Most values were within normal ranges by 4 or 14 days postexposure. No drug-related alterations in hematologic parameters were noted. Evidence of olfactory epithelial degeneration and desquamation in the nasal turbinates was noted at 4 days postexposure in male and female rats exposed to 202 ppm PIFE. Concentration-dependent renal tubular necrosis and tubular cell hyperplasia, in the corticomedullary border, were observed in males and females exposed to 114 and 202 ppm PIFE. The severity of tubular necrosis in both males and females was considered minimal to slight at the 114 ppm exposure concentration and slight to moderate at the 202 ppm exposure. Both the numbers of affected animals and severity were reduced over time. The most marked changes in serum and urine chemistry were associated with the animals described as having moderate renal necrosis. Male rats appeared more susceptible to nephropathy than female rats. There were no other PIFE-related histopathologic findings. CONCLUSIONS: The renal histopathologic findings in this study are consistent with those reported in previous acute studies in rats after PIFE administration. Functional changes in the kidney, as evidenced by serum chemistry and urinalyses, were observed at exposure concentrations that induced morphologic alterations.

Anesthetics, Inhalation↗
PubMed1995

The effect of sera antisperm antibodies in the female partner on in vivo and in vitro pregnancy and spontaneous abortion rates.

PROBLEM: To determine the incidence of antisperm antibodies (ASA) in female sera from infertile couples or those suffering from recurrent abortions. Also to determine if the pregnancy and/or abortion rates are any higher in those positive versus those negative for ASA. METHOD: All registered patients had sera drawn and ASA measured by indirect immunobead test on initial study. Pregnancy and abortion rates were determined for patients undergoing in vivo or in vitro therapy. RESULTS: There was a low incidence of ASA in patients having in vivo or in vitro treatment. There was no decrease in pregnancy rates (PRs) or increase in spontaneous abortions (SAB) in those positive for ASA. CONCLUSION: Antisperm antibodies in female sera do not seem to be etiologic in causing infertility or SAB. Future studies might consider changing the antigen source from donor sperm to husband's sperm.

Abortion, Habitual↗
PubMed1994

Comparison of the cumulative probability of pregnancy after in vitro fertilization-embryo transfer by infertility factor and age.

OBJECTIVE: To compare the cumulative probability of pregnancy after multiple IVF cycles by age and cause of infertility. DESIGN: A prospective study was done in which patients were followed from the time they registered for their first IVF cycle until they achieved a clinical pregnancy, withdrew from treatment, or study was terminated. PATIENTS, SETTING, TREATMENTS: Infertile women undergoing IVF-ET at the Cooper Institute for In Vitro Fertilization were enrolled in this study if the luteal phase leuprolide acetate (LA) and hMG controlled ovarian hyperstimulation (COH) regimen was used. MAIN OUTCOME MEASURES: Clinical pregnancy, as determined by a positive beta-hCG level and ultrasonographic confirmation of a gestational sac, and delivery rates based on number of women with live births were compared by infertility factor and age. RESULTS: The 3-month cumulative probability of pregnancy based on life table analysis was 33% in women with tubal factor who were < or = 35 years of age, 25% in women with tubal factor who were > 35 years of age, 30% for women with multiple factors who were < or = 35 years of age, and 14% for women with multiple factors who were > 35 years of age. The rate for the older women with multiple factors was significantly lower than that for the other groups. The delivery rates were lower for the women with multiple factors than for women under 35 with tubal factor only. CONCLUSIONS: There is a significant effect of age and infertility factor on pregnancy and delivery rates. Physicians should consider these factors in evaluating their patients' prospects for success in IVF-ET.

Adult↗
PubMed1994

Pregnancy rates in donors versus recipients according to the serum progesterone level at the time of human chorionic gonadotropin in a shared oocyte program.

Previous data suggested a subtle increase in serum P at the time of hCG injection without LH surge reduces the PR of women having oocyte retrievals for IVF; this study compared PRs of recipients in a shared oocyte program according to the donors' pre-hCG P level. There was no difference in viable PRs between recipients and donors when P < or = 1 ng/mL. The PR was similar for recipients when donors' P was > 1 ng/mL (12.7%). Donors with P > 1 ng/mL had the lowest PR: 7.2%. The data suggest that the adverse effect of higher serum P without LH surge may be on the endometrium rather than the oocyte.

Chorionic Gonadotropin↗
PubMed1993

Adverse effect of a homogeneous hyperechogenic endometrial sonographic pattern, despite adequate endometrial thickness on pregnancy rates following in-vitro fertilization.

We have previously presented data to show that in patients who had in-vitro fertilization (IVF)-embryo transfer using ovarian stimulation involving the luteal phase leuprolide acetate--human menopausal gonadotrophin (HMG) regimen, poor pregnancy results ensued if either the endometrial thickness was < 10 mm or a homogeneous hyperechogenic sonographic pattern was present immediately prior to taking a human chorionic gonadotrophin (HCG) injection. There were only 15 cases with this hyperechogenic type endometrium (and no pregnancies). The purpose of the present study was to evaluate the influence of a hyperechogenic endometrium when the endometrial thickness was > or = 10 mm, in a more extensive series, in women having IVF-embryo transfer using the same ovarian stimulation regimen. A total of 273 consecutive cycles, where endometrial thickness was > or = 10 mm, were evaluated (not including the 85 cycles previously reported). Of 22 patients with the hyperechogenic pattern, one achieved a chemical pregnancy (beta-HCG > 500 mIU/ml) and none achieved clinical pregnancies (ultrasound confirmation). In contrast, 67 of 251 (26.7%) patients conceived with other echo patterns (chi 2 analysis = 5.9, df = 1, P = 0.01). These data thus confirm, in a larger series, the negative influence of this type of echo pattern on subsequent pregnancy rates following the luteal phase leuprolide acetate--HMG ovarian stimulation regimen.

Embryo Transfer↗
PubMed1992

An evaluation of couples with failure of fertilization in vitro.

Attempts at in-vitro fertilization (IVF) may be used as a method of evaluating whether in a given couple, the inability of the sperm to fertilize the oocyte may be the cause of infertility. We evaluated all IVF patients in our practice who had at least one cycle with no fertilization to determine how often this was an isolated event or was repeated in multiple cycles; would poor semen quality be found as a frequent cause; and how well can a donor sperm or oocyte 'probe' uncover which of the two is the problem? Of 35 couples who used their own gametes exclusively, 30 (85.7%) had at least one cycle with zero fertilization; 42.5% of those failing to fertilize in cycle 1 and 35% of those failing in cycle 2 had a subnormal concentration of motile spermatozoa, morphology or hypo-osmotic swelling test scores. The pregnancy rate per cycle with both husband's and wife's gametes was only 2.3% (3/130), but was 8.3% for those using donor spermatozoa (3/36) and 18.2% (2/11) for donor oocytes. Thus, failing to fertilize in a given cycle does not necessarily predict failure to fertilize in a subsequent cycle, but does predict a poor fertility outcome unless donor gametes are used.

Adult↗