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Zinc is a key element for growth and development. In this narrative review, we focus on the role of dietary zinc in early life (including embryo, fetus and preterm neonate), analyzing consequences of zinc deficiency and adequacy of current recommendations on dietary zinc. We performed a systematic search of articles on the role of zinc in early life. We selected and analyzed 81 studies. Results of this analysis showed that preservation of zinc balance is of critical importance for the avoidance of possible consequences of low zinc levels on pre- and post-natal life. Insufficient quantities of zinc during embryogenesis may influence the final phenotype of all organs. Maternal zinc restriction during pregnancy influences fetal growth, while adequate zinc supplementation during pregnancy may result in a reduction of the risk of preterm birth. Preterm neonates are at particular risk to develop zinc deficiency due to a combination of different factors: (i) low body stores due to reduced time for placental transfer of zinc; (ii) increased endogenous losses; and (iii) marginal intake. Early diagnosis of zinc deficiency, through the measurement of serum zinc concentrations, may be essential to avoid severe prenatal and postnatal consequences in these patients. Typical clinical manifestations of zinc deficiency are growth impairment and dermatitis. Increasing data suggest that moderate zinc deficiency may have significant subclinical effects, increasing the risk of several complications typical of preterm neonates (i.e., necrotizing enterocolitis, chronic lung disease, and retinopathy), and that current recommended intakes should be revised to meet zinc requirements of extremely preterm neonates. Future studies evaluating the adequacy of current recommendations are advocated.

The hormonal activity of the pineal gland is influenced by both the dark-light cycle and the seasonal cycle, causing it to play an important role in the neuroendocrine control of reproductive physiology. This is especially evident in seasonally breeding animals, in which reproductive function is clearly influenced by seasonal variations in the duration of night and day. Humans are not seasonal breeders. Nevertheless, seasonal fluctuations have been described in human reproduction, and the pineal gland also appears to exert an important role in the neuroendocrine regulation of human reproductive physiology. There is evidence that the epiphysis is involved in the control of sexual maturation. In rats, the maternal pineal appears to influence the gonadal and genital development and function of offspring; this hypothesis has yet to be confirmed in humans. The pineal apparently influences human reproductive function not only at the hypothalamic-pituitary level, by inhibition of the hypothalamic pulsatile secretion of gonadotrophin-releasing hormone, but also at the gonadal level, where melatonin receptors have also been found. In addition, melatonin is reported to increase serum prolactin concentrations in both rats and humans. It has been suggested that melatonin is involved in the control of menstrual cyclicity.

A literature review of 22 cases of pregnancy following cardiac transplantation up to 1995 and a case report are presented here. A 30 year old woman, gravida 3, para 1, contacted us for obstetric care at 8 weeks gestation, about 55 months after orthotopic cardiac transplantation. The transplant had been performed for a familial dilative cardiomyopathy, which had become manifest during her previous pregnancy. The course of the current gestation was uneventful. The patient's cardiovascular function was good throughout the pregnancy. Immunosuppressive therapy, the dose of which was increased during pregnancy, included cyclosporine and azathioprine. Because of an increase in the patient's plasma uric acid concentration and an initial rise in her blood pressure, despite therapy, a repeat Caesarean section was performed at 37 weeks gestation. A female baby weighing 2330 g, Apgar scores 7/9, was delivered. Mother and infant were discharged on postoperative day 15 and are doing well 14 months postpartum. Through a review of literature and our case, the issues and problems related to pregnancy after a heart transplant are discussed, in particular the maternal-fetal risks, management, therapy, delivery, neonatal problems and follow-up postpartum of mother and baby.

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