Cover design The front cover of Human Reproduction shows two examples of faulty head-neck attachments in human spermatozoa. The configuration of the neckpiece of a normal spermatozoa is shown in the upper panel with the implantation fossa (curved arrow), basal plate (arrowheads), nuclear envelope (NE) and proximal centriole (asterisk) indicated. The lower left panel depicts an abnormal head-tail alignment with a defective head-mid-piece connection while the head and mid-piece in the lower right panel are at a 90;° angle. A vesicular structure (V) at the head-mid-piece junction is indicated. These abnormalities and numerous acephalic spermatozoa were observed in a series of 10 sterile men. The spermatozoa on the lower left panel come from a patient with a mixture of normal and acephalic spermatozoa and spermatozoa with abnormally aligned head-mid-pieces and loose heads. Four ICSI attempts with this patient resulted in fertilization, pronuclear development, but no cleavage. For further details, see pp. 1811-1818.
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