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Biomedical subjects

A Nazari

Publications and source records attributed to A Nazari.

At least 19 recordsLinked to original sources
PubMed2005

Non-homogeneous hyperechogenic echo pattern three days after frozen embryo transfer is associated with lower pregnancy rates.

OBJECTIVE: To evaluate the association of mid-luteal phase echo patterns and pregnancy rates (PRs) following frozen embryo transfer (ET). METHODS: Sonographic evaluation of endometrial echo patterns was performed three days after ET in the first frozen ET cycle of women < 40 years of age who used their own oocytes as well as all donor oocyte recipients. RESULTS: The distribution of echo patterns and clinical PRs were similar in women using their own eggs and women who used donor oocytes; therefore all data was combined. The clinical PR was 49.5% with a hyperechogenic echo pattern vs 38.8% with a non-hyperechogenic pattern, p = .007. CONCLUSION: A larger study of frozen ET and mid-luteal echo pattern now demonstrates conclusions similar to the data from fresh ET in hyperstimulated in vitro fertilization (IVF)-ET cycles in that failure to attain a hyperechogenic echo pattern three days after ET is associated with lower pregnancy rates.

Adult↗
PubMed2005

Ectopic pregnancy is not more likely following fresh vs frozen embryo transfer.

PURPOSE: To determine if the risk of ectopic pregnancy is greater following frozen vs fresh embryo transfer (ET). METHODS: Retrospective review of pregnancy outcome from January 1, 1997 to November 30, 2003. Cryopreservation was used as a simple freezing method and one-step removal of cryoprotectant. The cycles consisted mostly of graduated estradiol and progesterone supplementation. RESULTS: The ectopic pregnancy rate in 1,445 clinical pregnancies from fresh ET was 2.6% vs 2.0% of 975 clinical pregnancies resulting from frozen ET. CONCLUSION: In contrast to the conclusions of two previous studies, the present study evaluating twice as many clinical pregnancies than the two aforementioned studies combined failed to show any greater risk of ectopic pregnancy when transfers were performed on day 3.

Adult↗
PubMed2004

Neither sildenafil nor vaginal estradiol improves endometrial thickness in women with thin endometria after taking oral estradiol in graduating dosages.

PURPOSE: To determine if sildenafil improves endometrial thickness better than vaginal estradiol (E2) in women with a history of thin endometria. METHODS: Women failing to attain an 8 mm endometrial thickness on either the oocyte retrieval cycle or their first frozen embryo transfer (ET) despite an oral graduated E2 regimen were treated again with graduated oral E2 and were also randomly assigned to vaginal sildenafil or vaginal E2 therapy. Endometrial thickness was compared between the groups. RESULTS: Neither vaginal E2 nor sildenafil significantly improved endometrial thickness or blood flow in the subsequent frozen ET-cycle. CONCLUSIONS: These data fail to corroborate previous claims that 25 mg sildenafil four times daily intravaginally can improve endometrial thickness.

Administration, Intravaginal↗
PubMed2004

Possible mechanism(s) for relaxant effects of Foeniculum vulgare on guinea pig tracheal chains.

In a previous study the relaxant (bronchodilatory) effect of Foeniculum vulgare on isolated guinea pig tracheal chains was demonstrated. To study mechanisms responsible for this effect the present study evaluated the inhibitory effect of this plant on contracted tracheal chains of guinea pig. The relaxant effects of aqueous and ethanol extracts and an essential oil from Foeniculum vulgare were compared to negative controls (saline for aqueous extract and essential oil and ethanol for ethanol extract) and a positive control (diltiazem) using isolated tracheal chains of the guinea pig precontracted by 10 microM methacholine (group 1) and 60 mM KCl (group 2, n = 7 for each group). In the group 1, experiments diltiazem, ethanol extract, and essential oil from Foeniculum vulgare showed a significant relaxant effect on methacholine induced contraction of tracheal chains compared to those of negative controls (p < 0.05 to p < 0.001). In addition the effect of the ethanol extract was significantly greater than that of diltiazem (p < 0.001). However, the aqueous extract did not show any relaxant effect in group 1. In the group 2 experiments, only diltiazem showed a significant relaxant effect on KCl induced contraction of tracheal chains (p < 0.001). The relaxant effects of ethanol extracts and essential oil obtained in the group 2 experiments were significantly lower than those in group 1 (p < 0.05 to p < 0.001). These results confirm the bronchodilatory effects of ethanol extract and essential oil from Foeniculum vulgare. However with regard to the effect of KCl on calcium channels, the results indicated that the inhibitory effect of ethanol extracts and essential oil from Foeniculum vulgare on calcium channels is not contributing to their relaxant (bronchodilatory) effects on guinea pig tracheal chains. However the results suggest a potassium channel opening effect for this plant, which may contribute on its relaxant effect on guinea pig tracheal chains.

Animals↗
PubMed2002

Insecticide-treated plastic tarpaulins for control of malaria vectors in refugee camps.

Spraying of canvas tents with residual pyrethroid insecticide is an established method of malaria vector control in tented refugee camps. In recent years, plastic sheeting (polythene tarpaulins) has replaced canvas as the utilitarian shelter material for displaced populations in complex emergencies. Advances in technology enable polythene sheeting to be impregnated with pyrethroid during manufacture. The efficacy of such material against mosquitoes when erected as shelters under typical refugee camp conditions is unknown. Tests were undertaken with free-flying mosquitoes on entomological study platforms in an Afghan refugee camp to compare the insecticidal efficacy of plastic tarpaulin sprayed with deltamethrin on its inner surface (target dose 30 mg/m2), tarpaulin impregnated with deltamethrin (initially > or = 30 mg/m2) during manufacture, and a tent made from the factory impregnated tarpaulin material. Preliminary tests done in the laboratory with Anopheles stephensi Liston (Diptera: Culicidae) showed that 1-min exposure to factory-impregnated tarpaulins would give 100% mortality even after outdoor weathering in a temperate climate for 12 weeks. Outdoor platform tests with the erected materials (baited with human subjects) produced mosquito mortality rates between 86-100% for sprayed or factory-impregnated tarpaulins and tents (average approximately 40 anophelines and approximately 200 culicines/per platform/night), whereas control mortality (with untreated tarpaulin) was no more than 5%. Fewer than 20% of mosquitoes blood-fed on human subjects under either insecticide-treated or non-treated shelters. The tarpaulin shelter was a poor barrier to host-seeking mosquitoes and treatment with insecticide did not reduce the proportion blood-feeding. Even so, the deployment of insecticide-impregnated tarpaulins in refugee camps, if used by the majority of refugees, has the potential to control malaria by killing high proportions of mosquitoes and so reducing the average life expectancy of vectors (greatly reducing vectorial capacity), rather than by directly protecting refugees from mosquito bites. Mass coverage with deltamethrin-sprayed or impregnated tarpaulins or tents has strong potential for preventing malaria in displaced populations affected by conflict.

Afghanistan↗
PubMed2002

Live birth after posthumous testicular sperm aspiration and intracytoplasmic sperm injection with cryopreserved sperm: case report.

PURPOSE: To determine if a viable pregnancy is possible after aspiration of sperm from the testes of a man several hours after his death. METHOD: Following cryopreservation of the aspirated sperm, in vitro fertilization (IVF)-embryo transfer (ET) with intracytoplasmic sperm injection (ICSI) was used. The sperm selected were either those with motility or plumper non-motile sperm. RESULTS: Fertilization of oocytes and ET occurred following all five IVF-ET cycles. A clinical pregnancy was achieved in cycle 1 with non-motile sperm and a viable pregnancy resulted from cycle 5 with ICSI performed with viable sperm. CONCLUSION: Viable pregnancies following IVF-ET and ICSI are possible even when using testicular sperm obtained posthumously.

Adult↗
PubMed2002

The importance of number of blastomeres when embryos are transferred in the absence of controlled ovarian hyperstimulation.

PURPOSE: To determine if the previous findings that transferring embryos with a higher number of blastomeres results in higher pregnancy rates following fresh but not frozen embryo transfer (ET) was related to the use of controlled ovarian hyperstimulation (COH) in the former but not in the latter. METHODS: Retrospective review of pregnancy and implantation rates following fresh embryo transfer of donor egg recipient cycles (where no COH is used) vs frozen ETs during the same time period according to whether there was at least one embryo with eight blastomeres transferred or not. RESULTS: Significantly higher pregnancy rates with an 8-cell ET in donor oocyte recipient cycles but not frozen ETs. CONCLUSIONS: A less favorable uterine environment caused by the use of high dose gonadotropin is not responsible for the once again observed difference in higher pregnancy rates with higher blastomere number in fresh vs frozen ET. However, an effect of the gonadotropin releasing hormone analogue was not ruled out by this study.

Blastomeres↗
PubMed2001

Fresh embryo transfer is more effective than frozen for donor oocyte recipients but not for donors.

BACKGROUND: Recipients of donor oocytes need to be synchronized to the donor's cycle if fresh embryos are to be transferred on the cycle of oocyte retrieval. It would be much easier to merely retrieve the oocytes from the donor, fertilize the oocytes with the recipient's male partner's spermatozoa, cryopreserve the embryos, then transfer on an oestrogen/progesterone treatment programme. METHODS: The IVF outcomes of all patients enrolled in a shared oocyte programme from January 1997 to June 1999 were reviewed. Pregnancy and implantation rates were computed and statistically analysed. RESULTS: There was a significantly higher clinical pregnancy rate for recipients who had a fresh embryo transfer compared with recipients whose first embryo transfer consisted of frozen/thawed embryos (63.4 versus 43.6%). CONCLUSIONS: Conception is more likely after fresh than frozen embryo transfer with recipients but is similar to donor conception rates. If a uterine defect, per se, even without the use of the controlled ovarian stimulation regimen, could explain the difference between fresh pregnancy and implantation rates in donors versus recipients, then these same differences would have been seen when comparing frozen transfers, but they were, in fact, similar.

Adult↗
PubMed2001

Pregnancy rates (prs) according to embryo cell number at time of embryo transfer (ET).

PURPOSE: To evaluate pregnancy and implantation rates following fresh and frozen embryo transfer (ET) according to blastomere number. METHODS: A retrospective study from 1/1/97 to 9/30/98 including all cycles with ETs irrespective of age. RESULTS: 65% of fresh transfers had at least one 8-cell embryo vs only 39.6% for frozen ET. The clinical pregnancy and implantation rates were higher when one 8-cell embryo was transferred (64% and 24%) vs a 5-7 cell embryo (41% and 14.5%) for fresh transfers. There was less of a difference with frozen ETs (46% and 19% for 8-cell vs 38% and 17% for 5-7 cell). CONCLUSIONS: Since mostly only 8-cell embryos at day 3 reach the blastocyst stage, these data raise questions as to whether the quest to attain the highest pregnancy rate per transfer through blastocyst transfer, may be at the expense of overall pregnancy rate (fresh and frozen) from a given oocyte harvest.

Adult↗
PubMed2001

Cumulative pregnancy rates after four embryo transfers of either fresh or frozen embryos.

PURPOSE: To evaluate in the modern era of in vitro fertilization (IVF) cumulative probability of pregnancy for the first four embryo transfers (ET) irrespective of whether the embryos were fresh or frozen. METHODS: Retrospective review over a 2 1/2 year period. Cumulative probability of pregnancy for four consecutive cycles of either fresh or frozen ETs divided into four age groups. RESULTS: The cumulative clinical and viable pregnancy rates after four ETs were 92% and 88%; 87% and 82%; 83% and 69%; and 68% and 52% for age groups <30, 30-34, 35-39, and 40-44. The cumulative rates decline with age. CONCLUSIONS: Pregnancy rates per transfer for the first four ETs regardless of age are similar even in IVF centers that emphasize frozen ETs.

Adult↗
PubMed2001

Marked improvement in clinical pregnancy rates following in vitro fertilization-embryo transfer seen when transfer technique and catheter were changed.

PURPOSE: To compare in vitro fertilization (IVF) outcome with two different embryo transfer (ET) catheters: the Frydman and Wallace catheters. METHODS: Retrospective review of outcome of IVF cycles where there was at least one embryo that had assisted hatching prior to transfer at 72 hours according to which catheter was used. RESULTS: Pregnancy rate 17.6% per transfer with Frydman (FET-SET) vs 44.2% for fresh ETs and 15.4% and 43.2% for frozen ETs. The implantation rates for fresh ETs were 7.6% vs 20.0% for fresh and 5.7 vs 21.1% for frozen ETs. CONCLUSION: The soft Wallace catheter is superior to the stiffer Frydman catheter when transferring embryos subjected to assisted embryo hatching.

Catheterization↗
PubMed2000

Hyperreactio luteinalis despite the absence of a corpus luteum and suppressed serum follicle stimulating concentrations in a triplet pregnancy.

Hyperreactio luteinalis is characterized by moderate to marked cystic enlargement of the ovaries related to multiple theca lutein cysts and is associated with very high sex steroid concentrations. It is a rare condition especially in the first trimester. The case described below is believed to be the only case of hyperreactio luteinalis reported following frozen embryo transfer. This case provides an opportunity to gain further insight into the mechanism responsible for this unusual condition. The 30 year old woman demonstrated a slightly elevated LH/FSH ratio (5 and 3 mIU/ml respectively) and normal baseline androgen concentrations. Two years following oocyte retrieval she had a second frozen embryo transfer. The ovaries were normal size when the embryos were transferred and androgens were still normal. The ovaries did not begin to enlarge until 51 days from transfer. A dichorionic intrauterine pregnancy with monozygotic twins in the left gestational sac was seen. Eventually, 86 days from transfer, the ovaries enlarged to 145x103x116 mm right; and 83x95x117 mm left. Serum oestradiol was 30 078 pg/ml, beta-human chorionic gonadotrophin (HCG) 239 920 mIU/ml, serum progesterone >160 ng/ml, total testosterone 2254 ng/dl, free testosterone 42.3 pg/ml and androstenedione 7328 ng/dl. Throughout the first trimester, serum FSH was <1 mIU/ml. Thus, neither FSH nor a corpus luteum is necessary to initiate this syndrome.

Adult↗
PubMed2000

No evidence of increased uterine vascular impedance with patient ageing following IVF.

A study was conducted to determine if uterine vascular impedance increases with advancing age in women undergoing ovarian stimulation for IVF. A group of 162 women who had undergone conventional IVF and embryo transfer was subdivided into three subgroups by age: 30-34 years (n = 49), 35-39 years (n = 79) and 40-44 years (n = 34). The pulsatility index (PI) and resistance index (RI) of the right and left uterine arteries were measured at baseline, on the day of oocyte retrieval, and at the mid-luteal phase. There were no differences in the average PI or RI by age at any phase of the cycle. In all age groups, the luteal phase values of PI and RI were lower than those observed earlier in the cycle. Endometrial thickness was not associated with age. There was no significant correlation between PI, RI and serum oestradiol and progesterone concentrations at any phase of the cycle. Ovarian response, as measured by average number of oocytes retrieved, decreased significantly with age. Thus, reduced pregnancy rates in older women undergoing ovarian stimulation are more likely to occur because of oocyte quality and quantity rather than uterine senescence. If future studies determine that the use of ovarian stimulation does decrease implantation rates more in older versus younger women, a mechanism other than increased uterine vascular impedance must be sought.

Adult↗
PubMed2000

A study to determine if certain sonographic uterine parameters are associated with multiple gestation.

The objective was to determine if lower uterine artery vascular impedance is associated with a greater likelihood of multiple gestation. Color Doppler parameters of pulsatility index, resistance index, endometrial thickness and echo patterns were measured in oocyte/retrieval cycles on days of human chorionic gonadotropin injection, oocyte retrieval, and mid-luteal phase in cycles where at least 3 embryos were transferred. Comparisons of these parameters were made in patients with single versus multiple gestations. There was no association between uterine environment as measured by vascular impedance and endometrial thickness and number of embryos implanted. Thus, a more ideal uterine environment, at least as determined by these sonographic parameters, does not seem to facilitate multiple embryo implantations.

Adult↗
PubMed2000

Successful pregnancy following in vitro fertilization-embryo transfer despite imminent ovarian failure.

There have been previously published several anecdotal cases of women in apparent or imminent ovarian failure who subsequently ovulated and became pregnant. Many of these women had been treated with estrogen. A series of cases were reported where women with hypergonadotropic hypogonadism who failed to stimulate despite gonadotropin therapy were able to ovulate when treated with pharmacologic doses of estrogen alone or in combination with human menopausal gonadotropins. Presented herein is a case of a woman with imminent ovarian failure with tubal disease who failed to stimulate with gonadotropins alone but was successful with estrogen and gonadotropins. We believe this is the first successful case of hypergonadotropic hypogonadism to conceive by in vitro fertilization.

Adult↗
PubMed2000

The presence of small uterine fibroids not distorting the endometrial cavity does not adversely affect conception outcome following embryo transfer in older recipients.

PURPOSE: To determine if uterine fibroids have a negative impact in older patients having embryo transfer (ET). METHODS: Comparison of clinical and viable pregnancy rates, implantation rates, and spontaneous abortion rates in older (>35) oocyte or embryo recipients with uterine leiomyomata compared to comparable patients without fibroids. RESULTS: The clinical pregnancy rate per transfer was 56% in the fibroid group vs 64% for the controls. Implantation rates were also very similar (33 vs 32%7). There were no spontaneous abortion or preterm deliveries <32 weeks in the fibroid group and the average term of pregnancies was also similar. CONCLUSION: Small fibroids not distorting the uterine cavity do not seem to negatively affect conception outcome even in older women.

Adult↗
PubMed1998

A matched study to determine whether low-dose aspirin without heparin improves pregnancy rates following frozen embryo transfer and/or affects endometrial sonographic parameters.

PURPOSE: The objective of the matched, controlled study was to determine whether low-dose aspirin therapy without heparin improves pregnancy rates following frozen embryo transfer. METHODS: Thirty-six women who did not achieve a pregnancy following fresh embryo transfer and who had frozen embryos available for another transfer were included. Eighteen women were treated with 81 mg aspirin from day 2 of the cycle through pregnancy testing. If the beta-human chorionic gonadotropin level was positive, aspirin was continued through the pregnancy. Eighteen women were not given aspirin. The mean outcome variables were pregnancy and implantation rates. RESULTS: The clinical pregnancy rate in the aspirin group was 11.1%, compared with 33.3% for the controls, and implantation rates were 2.9 and 10.9%, respectively. CONCLUSIONS: No positive effects of low-dose aspirin therapy on pregnancy rates following frozen embryo transfer were observed.

Antibodies, Antiphospholipid↗