Relationship between abnormal sperm chromatin packing and IVF results.
(57/1639)
This study was initiated to determine the relationship between the fertilizing potential of spermatozoa and abnormalities in the compact packing of their chromatin which occurs in the final stage of male germ cell differentiation. Chromatin packing involves disulphide bridge covalent cross-linking. The degree of packing was determined from the accessibility of DNA to a fluorescent dye, ethidium bromide, following detergent treatment of the spermatozoa. The amount of dye bound was determined by flow cytometry in the presence or absence of heparin, a polyanion which removes only non-disulphide bridge-linked proteins. The results of a number of different sperm samples were compared with their results following in-vitro fertilization, and a relationship between disordered sperm chromatin packing and rates of embryo cleavage was observed. This study suggests that abnormal chromatin packing in spermatozoa may contribute to male fertility. (+info)
Effect of duration of dominance of the ovulatory follicle on onset of estrus and fertility in heifers.
(58/1639)
In cattle, prolonged progestogen treatments following luteolysis result in persistent dominant follicles (DF) that are associated with precise onset of estrus but marked reductions in pregnancy rate (PR). The aim was to determine whether increasing duration of dominance of the ovulatory follicle in heifers affected 1) precision of onset of estrus and 2) the timing and nature of the decline in PR. In Exp. 1, duration of dominance of the ovulatory follicle was controlled by causing corpus luteum (CL) regression at emergence of the second follicle wave (mean duration of dominance of 2.1+/-.3 d, Dm2, n = 11) or first day of dominance of the second DF of the cycle; the latter was combined with insertion of a 3-mg norgestomet ear implant for 2 to 10 d to maintain the second DF for 4 (Dm4, n = 32), 6 (Dm6, n = 19), 8 (Dm8, n = 49), 10 (Dm10, n = 28), or 12 d (Dm12, n = 20). Heifers detected in estrus were inseminated approximately 12 h later with frozen-thawed semen. Durations of dominance of the ovulatory follicle of up to 8 d did not affect (P>.05) PR (Dm2 8/9, Dm4 19/28, Dm6 14/18, and Dm8 34/48 heifers pregnant), but PR in Dm10 heifers (12/23 heifers pregnant) was reduced (P = .05) compared with Dm2 heifers; PR in Dm12 heifers (2/17 pregnant) was less compared with all other treatments (P<.01). Fitting a logistic regression model to the pooled PR data to examine the trend in PR showed that extending the duration of dominance from 2 to 9 d and from 10 to 12 d resulted in a predicted decline in PR of 10 to 25% and a further decline of 35 to 75%, respectively. Onset of estrus was delayed in heifers assigned to Dm4 treatment relative to all other treatments (P<.001); it was less variable than that for heifers on Dm6, Dm8, and Dm10 treatments (P<.1). In Exp. 2, heifers received a PGF2alpha analogue and a norgestomet implant on d 12 of the cycle for 3 or 7 d to give approximate durations of dominance of the preovulatory follicle of 2 to 4 d (Dm2-4, n = 29) or 6 to 8 d (Dm6-8, n = 24), respectively. The PR did not differ (P>.05) between heifers on Dm2-4 (22/29) and Dm6-8 (15/24) treatments, but the interval to onset of estrus was delayed (P<.05) by 7 h in the Dm2-4 heifers. In conclusion, restricting the duration of dominance of the preovulatory follicle to < or =4 d at estrus, results in a precise onset of estrus and a high PR following a single AI at a detected estrus. (+info)
Exposure to toluene in the printing industry is associated with subfecundity in women but not in men.
(59/1639)
OBJECTIVE: To examine the possible influence of exposure to toluene on human fertility. METHODS: In a cross sectional study, a sample of 150 male and 90 female printing industry workers were interviewed retrospectively on reproductive experience with a modified version of the European study of infertility and subfecundity questionnaire. Exposure categories comprised job descriptions and information on exposure measurements obtained by industrial hygienists. The fecundability ratio (FR) was estimated on the basis of time to pregnancy (TTP) or periods of unprotected intercourse not leading to pregnancy (PUNP) by means of survival analysis with proportional hazard models. Confounders such as age, ethnicity, smoking, parity, pelvic inflammatory diseases, and frequency of sexual intercourse were controlled for in the analyses. RESULTS: 256 Periods of TTP or PUNP were reported by men and 174 by women. After exclusion of induced abortions, birth control failures, and periods without employment for female workers we were able to analyse 169 periods in men and 100 periods in women. Male workers who had been exposed to different concentrations of toluene and their partners did not show a reduction in fecundity. In women (39 periods occurred during exposure) fecundity was reduced (FR 0.47, 95% confidence interval (95% CI) 0.29 to 0.77). Neither, restriction to only the first period nor exclusion of PUNPs changed the results (FR 0.48, 95% CI 0.24 to 0.97). CONCLUSION: After considering possible biases, low daily exposure to toluene in women seems to be associated with reduced fecundity. This result is in accordance with other findings for organic solvents and supports both the hypotheses that (a) organic solvents could affect hormonal regulation, and that (b) organic solvents increase early fetal losses which in turn contributes to longer times of unprotected intercourse. (+info)
Reproductive outcome after sterilization reversal in women of advanced reproductive age.
(60/1639)
OBJECTIVE: Our objective was to assess the clinical outcome of tubal reversal in women of advanced reproductive age. METHODS: A multicenter retrospective chart review of 153 patients who underwent a tubal ligation reversal was carried out. Patients were evaluated according to age. All patients had documented ovulation and a partner with a normal semen analysis by WHO criteria. Outcome measures included rates of clinical pregnancy, ectopic pregnancy, spontaneous abortion, and live birth, and the time to conception. RESULTS: Clinical pregnancy rates were significantly lower in women > or = 40 compared to younger groups. The time to conception was significantly shorter for women < 30 compared to women > or = 35. No pregnancies occurred in women > or = 42. CONCLUSIONS: Our data support the judicious use of sterilization reversal for infertile women with no male factor through their early forties. Women > or = 42 years should be especially counseled as to the very low success rates. (+info)
The outcome of cryopreserved human embryos after intracytoplasmic sperm injection and traditional IVF.
(61/1639)
OBJECTIVE: Our objective was to analyze the outcome of cryopreserved embryos obtained after intracytoplasmic sperm injection (ICSI) and in vitro fertilization (IVF) in terms of survival rate, implantation rate (IR), total and clinical pregnancy rate (PR) in a retrospective, comparative study. METHODS: Three hundred seventy-five IVF and 463 ICSI surnumerary cleaved embryos, frozen on Day 2 with 1,2-propanediol, were thawed. RESULTS: Thirty-two percent of the thawed IVF embryos survived and 11 pregnancies (8 clinical) were obtained from 68 transfers (16.1%). Fourty-seven percent of the ICSI embryos survived, with 19 pregnancies (18 clinical) from 116 transfers (16.4%). The IR was 8.5% (8/94) in IVF cycles and 10.8% (20/185) in ICSI cycles. CONCLUSIONS: A significantly better survival rate of ICSI embryos was observed but with no difference in PR, preclinical, and clinical abortion rate, or IR. (+info)
The effect of endometrial polyps on outcomes of in vitro fertilization (IVF) cycles.
(62/1639)
PURPOSE: Our purpose was to investigate the effect of endometrial polyps on pregnancy outcome in an in vitro fertilization (IVF) program. METHODS: Endometrial polyps less than 2 cm in diameter were suspected by transvaginal ultrasound before oocyte recovery in 83 patients. Forty-nine women (Group I) had standard IVF-embryo transfer, while in 34 women (Group II) hysteroscopy and polypectomy were performed immediately following oocyte retrieval, the suitable embryos were all frozen, and the replacement cycle took place a few months later. RESULTS: Of the 32 hysteroscopies, a polyp was diagnosed in 24 cases (75%) and polypoid endometrium in another 5 patients (15.6%). An endometrial polyp was confirmed by histopathological examination in 14 women (58.3%). The pregnancy rate in group I was similar to the general pregnancy rate of our unit over the same period (22.4 vs 23.4%) but the miscarriage rate was higher (27.3 vs 10.7%, P = 0.08). In Group II, the pregnancy and miscarriage rates were similar to those of the frozen embryo cycles at Bourn Hall (30.4 and 14.3 vs 22.3 and 12.1%, respectively). CONCLUSIONS: Small endometrial polyps, less than 2 cm, do not decrease the pregnancy rate, but there is a trend toward increased pregnancy loss. A policy of oocyte retrieval, polypectomy, freezing the embryos, and replacing them in the future might increase the "take-home baby" rate. (+info)
Controlled ovarian hyperstimulation adversely affects implantation following in vitro fertilization-embryo transfer.
(63/1639)
PURPOSE: Our purpose was to determine if controlled ovarian hyperstimulation adversely affects implantation. METHODS: A retrospective comparison of pregnancy rates (PRs) and implantation rates was made between oocyte recipients versus their donors, who shared half of the retrieved oocytes, and regular patients undergoing in vitro fertilization-embryo transfer (IVF-ET) who were not sharing eggs. RESULTS: Higher implantation rates (39.0 vs 22.5%; P < 0.05) were found in recipients compared to donors in the stimulated cycle. However, no differences were seen in PRs or implantation rates in frozen ET cycles. The data for standard IVF patients were almost-identical to those for donors. CONCLUSIONS: Superior implantation rates and PRs in oocyte recipients versus donors were not related to better oocyte quality for recipients because of egg sharing or to a better uterine environment because of similar results with frozen ET in all three groups. An adverse effect of the hyperstimulation regimen best explains the difference. (+info)
Assessment of the dominant abnormal form is useful for predicting the outcome of intracytoplasmic sperm injection in the case of severe teratozoospermia.
(64/1639)
PURPOSE: Our purpose was to investigate the relation between the dominant sperm anomaly and sperm morphology and the outcome of intracytoplasmic sperm injection (ICSI). METHODS: Two hundred ninety-five patients who underwent a total of 181 cycles of in vitro fertilization (n = 168) and/or 217 cycles of ICSI (n = 177) between July 1995 and May 1997 at Keio University Hospital were investigated. RESULTS: The rates of fertilization and pregnancy were 63.3 and 27.8%, respectively, in ICSI cycles with < or = 4% normal forms. When the percentage of strictly normal morphology was < or = 4, the fertilization rate was lower in the case of severely tapered head (13.0%; n = 4) than in the cases of other deformities in ICSI. The acrosomal defect made no difference in the fertilization rate with ICSI. CONCLUSIONS: The predominant abnormal form affects the ICSI outcome in the case of < or = 4% normal forms. (+info)