Abstract During mammalian development the growth of the fetus is regulated by genetic information that is inherited from both the sperm and the oocyte. Apart from the clear differences that…

Abstract The first live births following frozen-thawed embryo transfer were reported in 1984 and 1985 by groups in Australia, the Netherlands and the United Kingdom. Since that time, the original…

Abstract Preimplantation genetic diagnosis (PGD) was developed in the late 1980s to help couples who are at risk of transmitting an inherited disease to their offspring, as an alternative to…

Abstract During the transition from morula to blastocyst the embryo enters the uterus, where it is sustained by oxygen and a rich supply of metabolic substrates in uterine secretions. The…

Abstract At least 50% of couples referred for infertility investigation and treatment are found to have a contributing male factor. Male factor infertility can represent a variety of defects, which…

Abstract Every cell in an individual has a unique chromosome complement, with 20 000–25 000 genes coded into a DNA sequence of 3 billion base pairs, packed into 23 pairs of chromosomes:…

Abstract In the armory of medical technology available for alleviation of disease and quality of life enhancement, there is nothing to match the unique contribution of assisted reproductive technology (ART)….

Abstract From the beginning of the twenty-first century onwards, laboratories that offer human ART treatment or are involved in the handling of human gametes and/or tissue became subject to increasing…

Abstract After completing fertilization with fusion of the pronuclei during syngamy, the zygote now has a diploid complement of chromosomes, undergoes its first mitotic division and then continues to divide…

Abstract Mature human gametes ready for fertilization differ in their state of nuclear maturation: the spermatozoon has completed meiosis and the oocyte is arrested at metaphase II. However, both gametes…