Background & Objectives: Neonatal mortality rate is a main indicator of hygienic development and recognition of the mortality causes is the first step for reduction of the mortality rate and promotion of this indicator. Therefore, in this study, the causes of neonatal mortality have been investigated in Ardabil medical university related hospitals.

  Methods: This study is a retrospective, cross-sectional and descriptive-analytical one that has been done on the bases of admission's units and filling the medical record form for all neonates who have been admitted to Alavi and Imam Khomeini hospitals in Ardabil from September 2006 to September 2007. The questions of forms consisted of infant’s sex, birth weight, gestational age, cause and age of death. The data were analyzed by SPSS software with utilizing T- test and Chi-Squares.

  Results: During this study, there were 1881 admissions of which there were 148 deaths (7.86%). The causes of mortality were hyaline membrane disease (HMD) (52.02%), sepsis (14.86%), pneumonia (9.45%), congenital anomaly (12.83%), asphyxia (7.43%) and meconium aspiration (3.37%). Among the dead neonates, 54.72% were male and others were female. There were 550 LBW neonates and 111 deaths in this group result of our study showed that mortality rate in LBW neonates was 20.18%. There were 578 preterm neonates and 122 deaths in this group prevalence of mortality rate in preterm neonates was 21.10%.

  Conclusion: Prematurity and low birth weight are the most important and fixed cases of infant mortality. The most common causes of mortality were hyaline membrane disease and sepsis. Therefore, the prevention of preterm labor for reduction of prematurity and its related complication recommended which may lead to decreased rate of neonatal mortality.

  Background & Objectives: Birth weight less than 2500gr (as result of preterm delivery and/or intrauterine growth restriction (IUGR)) is a major cause of both neonatal health. Predominate cause of LBW in developed countries is premature birth, whereas in developing countries is more often IUGR. Different risk factors, including demographic and behavioral during and before pregnancy are effective in LBW incidences which can reduce LBW and neonatal mortality rate by identification and control of these risk factors. The present study has been carried out with purpose of identification and decreasing the LBW rate in Ardabil.

 Methods: In this case – control study all infants delivered in 2006 in hospitals in Ardabil were investigated. Every neonate whose weight was less than 2500gr was taken as a case (n=470) and 482 neonates whose weight was more than 2500gr was taken as a control. Data gathering was done through questionnaires, interviewing the mothers and physical examination. The data were analyzed statistically through SPSS.

 Results: In the present study, the presence of LBW amount is %6.4 in Ardabil hospitals. The results of our study showed that a significant relationship existed between prematurely and gestational age<37wk, mother’s age, mother’s job and maternal weight, premature rupture of membranes (PROM), maternal diseases, multiple births, bleeding during pregnancy, interval between pregnancies less than <2 years, prior history of low birth weight, use of drugs by mother in pregnancy, congenital malformation with LBW. In this study relation between parity, the use of Folic Acid, Fe, cigarette smoking and addiction of mother, living area (village or city), family marriage, health care and mother’s education were not significant with LBW.

  Conclusion: The LBW important risk factors in Ardabil hospitals were prematurity or gestational age <37wk, multiple pregnancies, PROM, mother’s age over 35 years, and mother weight <50kg, maternal diseases.

  Background & objectives : Infertility is a global problem affecting millions of men and women in developed and developing countries. In this regard, in-vitro fertilization (IVF) plays an important role in improving the quality of life in infertile patients. However, studies have shown that the implantation failure in IVF is the main challenge of this procedure. Melatonin can increase the survival rate of embryos and IVF success rate through eliminating free radicals and removing reactive oxygen species. So, this study is conducted to investigate the effects of different concentrations of melatonin on the rate of newborns of mice following transfer oftwo-cell embryos .

  Methods : In this study, female mice with average age of six to eight weeks were superovulated by administering pregnant mares serum gonadotropin (PMSG) intraperitoneally (7.5 IU. ip), and followed after 48h by human chorionic gonadotropin (hCG) (7.5 IU. ip). Two-cell mouse embryos were obtained from female mice oviduct after 48 h. The embryos transferred bilaterally into pseudopregnant mice of the same strain through surgical procedure and 8-14 embryos were transferred to each tube. The study included 4 treatment groups and one control group (6 mice in each group). The treatment groups were exposed to subcutaneous injection of concentrations of 100 µm , 10 µm , 1 µm and 100 nm of melatonin. After the cesarean on 18^th day of pregnancy, the percentage of live births was assessed. The outcomes of the live birth rate were as­sessed using the chi-square test and statistical analyses were carried out using SPSS version 16.0. Percentage of live birth was calculated and compared with the control group.

  Results: A total of 701 two-cell mouse embryos were transferred into one control group and four experimental groups. The number and percentage of live births at concentrations of 100 µm and 10 µm of melatonin and the control groups were 21 (15.55%), 13 (9.15%) and 9 (6.47%), respectively. No infant was born at the concentrations of 1 µM and 100 nM of melatonin . The highest rate of live births was obtained at the concentration of 100 µM and showed a significant difference with the control group (p ≤ 0.01). There was no significant difference in live births at the concentration of 10 µm and control group.

  Conclusion : The results of this study indicated that subcutaneous injection of melatonin improves the two-cell mouse embryo growth and post implantation development of mice.