Background: Assisted hatching techniques are utilized to facilitate the embryo escape out of the zona pellucida and increase the pregnancy rates in IVF centers. The objective of this study was to evaluate if assisted hatching improved the rates of pregnancy for in-vitro fertilization, in Isfahan Infertility Center.Materials and methods: This case-control study was carried out on 296 infertile patients. Patients with assisted hatching were 131 (case group) and non-treated patients were 165 (control group). Patients' age, number of oocytes aspirated, number of oocytes fertilized, and numbers of embryos transferred were matched. The pregnancy was determined by positive b-HCG, 14 days after transfer; and implantation was defined as presence of gestational sac in uterus on sonography. Statistical analysis was done with the student t-test and X2 test. A Pvalue of less than 0.05 was considered statistically significant.Results: No significant difference was noted in the mean age of patients, the number of oocytes aspirated, the number of oocytes fertilized, and the number of embryos transferred between the case and control groups. In addition, no significant difference was observed in the rates of pregnancy between the hatched and control groups (22.9% versus 20.6%, respectively).Conclusion: Assisted hatching has no significant impact on pregnancy rates in the patients population studied. Further data are needed to determine if assisted hatching has beneficial effect on pregnancy rate.

The Fisheries Research Laboratory, University of Zabol to investigate the Effect of different levels factors of pH on the percentage of hatching (HP) and hatching efficiency (HE) cysts Artemia urmiana at five different pH (7, 7.5, 8, 8.3 and 9) were performed. Each treatment was replicated three times. During the experiment, all factors affecting hatching was fixed and the variable pH levels. After 24 hours of incubation system began, the number of nauplii and umbrella cysts forms and cysts were counted and the percentage of hatching capacity was calculated. Based on the results, the percentage of hatching ability of pH=8.3 was higher than other treatments and at hatching was observed at pH=9. Differences between treatments were very small and statistically not significant (P>0.05). Generally, the pH is an important factor in the hatched Artemia urmiana cysts and for optimization of the pH must be kept constant at 8.3.

Background: For infertile women aged over 35 years, failure of the ZP (zona pellucida) to rupture is believed to be associated with a decreased implantation rate in in vitro fertilization (IVF) or intra cytoplasmic sperm injection (ICSI).Objective: In this research, laser assisted hatching (LAH) was offered to patients with advanced maternal age to evaluate a possible benefit.Materials and Methods: Nine hundred thirty two cycles of IVF/ICSI in females were analyzed. Women included in this study were allocated in 4 groups. In group I and II, embryos were cultured and transferred with and without LAH in women aged £35, whereas embryos of group III and IV were examined with and without LAH in women aged ³ 35. Laser manipulations were performed using a suturn-Tm3 system using 2-3 pulses of 0.8 millisecond with 400 voltage duration. The size of the hole made in the zona was measured to be 5-10 mm, depending on the zona thickness of each individual embryo.Results: The performance of LAH significantly increased clinical pregnancy rates in all patients. In group I and II, the chemical (50.99% and 31.61% respectively), clinical (50% and 30.69% respectively) and multiple pregnancies (22.27% and 5.94% respectively) significantly differ between these groups. In the patients with advanced female age ³35 the performance of LAH significantly increased chemical (30.12%) and clinical pregnancy (27.71%) rates compared to whom without LAH (18.96% and 16.37% respectively).Conclusion: Our data demonstrate in the patients who were less than 35 years old, multiple pregnancy rates were significantly increased compared to other groups who aged over 35 years old. In addition benefit of LAH in improving pregnancy rates after IVF or ICSI in women of advanced age (³35) was shown.

Nauplii in the Instar I –II stages are probably the form of Artemia most widely used in aquaculture. They are also the easiest and earliest live food obtained from the cysts. In order to optimize utilization of cysts for hatching into nauplii, it is useful to know as much as possible about the hatching characteristics of each batch. and in this regard, the critical factors are: temperature, salinity, and pH. Three-way ANOVA with three factors each with three levels including, water salinity (28, 30 and 33ppt), water temperature (25, 28 and 30°C) and pH (7, 8 and 9) has been analyzed on the hatching efficiency of Artemia urmiana cysts for determining the best points of these physical parameters in laboratory condition. There are significance differences between salinity, water temperature and interaction S* W. T, S*pH and W. T*pH (p<0. 05) but there are not any differences between pH treatment and S*W. T*pH interactions The best points are 30ppt, 28°C and 7 for water salinity, water temperature and pH respectively.

The effects of some abiotic factors (pre-incubation condition, floating in 1% NaOCL, temperature and photoperiod) was investigated on the hatching response of Daphnia similis ephippial eggs collected from live food ponds in cultivation centre of Gorgan. After isolation, the eggs were kept in dry and wet conditions at 4oC for 2 months in darkness. Following the pre-incubation period, the eggs in each group were subdivided into 2 parts and treated with1% NaOCL and distilled water. The effect of temperature levels (20oC, 25oC and 30oC) and photoperiod levels (12L: 12D and 24L: 0D) were identified on the hatching of eggs in AdaM medium during 15 days. Results indicated that the exposure of wet eggs of Daphnia similis to 12-hour photoperiod and 20oC after soaking in 1% NaOCL, increased the maximum rate and speed of hatching. These ephippial eggs significantly reacted more rapidly while keeping in wet condition at 20oC but no significant difference (P>0/05) in shortening time until hatch was observed among different levels of photoperiod and floating in 1% NaOCL.

Studies showed that Thyroxine can play an important role on fish growth, osmoregulation system, and other physiological activities. Since the direct effect of thyroxine on growth and metamorphose of bony fish larvae has not been yet approved, therefore, present study were carried out in Shahid Ansary propagation and cultivation farm in order to find out the way of effect of this hormone on the survirval rate and early growth stage of silver carp (Hypophthalmichthys molitrix) fertiled eggs that were bathed in thyroxin with concentrations of 0.1, 0.5 and 1.0 ppm (each one, replicates) for 6 hours. Then they were transfered into large incubators (zoog) with running water. After hatching all larvae were placed in mentioned thyroxin concentration bath for another 6 hours before being transfered into large incubators.Larvae stayed inzoogs until the yolk-sac was absorbed. Finally, live silver carp larvae were counted in separated plates. Results of present study indicated that the ra tio of hatched eggs in 0.5 ppm of thyroxin concentration was higher than other treatment.

The present study has been conducted to determine the effect of different light intensities on Artemia urmiana cysts hatchability. The effect of seven light intensities consisting darkness, 500, 1000,1500, 1700, 2000, 2500 Lux were assessed, each treatment had three replicates. All factors affecting cysts hatching were constant except illumination. 24 hours after incubation the number of nauplii, umbrella stage and unhatched cysts were counted and hatching percentage determined. According to results the hatching percentage was significantly higher than other treatments, and the less hatching was occurred in darkness. Illumination is one of the most important factors in artemia cyst hatching, and the light intensity should be about 2000Lux during Artemia urmiana incubation.