Word: sperms
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...natural mistake given his maverick image. Will independents like him less when they learn more?) McCain's construction that life begins "at the moment of conception" opens a whole new set of questions. There is a world of mystery in what transpires between the moment when egg meets sperm and the point of implantation, when that fertilized egg nestles into the uterus and begins to grow...
Consider the obvious implications if rights attain the moment the egg and sperm meet: all kinds of embryo research become questionable, starting with the stem-cell research McCain says he favors. Couples who undergo in vitro fertilization and then choose not to implant all the embryos are surely violating the rights of those that are discarded or frozen. Some forms of contraception, such as IUDs and the morning-after pill, would presumably be illegal if they affect the ability of an egg to implant. Abortion opponents contend that the birth control pill itself, while designed to prevent ovulation...
...Fully fed and assured of more food whenever they wanted it, the youthful oysters turned their energies and attention to their sexual organs, leaving the rest of their system vulnerable to herpes infection. "Once sufficiently nourished to ensure for survival, oysters focus on development of sexual organs - creating sperm and ovaries mostly - and ignore their defense systems," explains Tristan Renault, the director of Ifremer's genetic and pathology laboratory. "Oysters are capable of only one function at once, especially in springtime. So if a threat is posed during this period of concentrated sexual development, they're very susceptible...
...research would suggest several other options are possible. Studies show that the right combinations of testosterone and a progestin can successfully and reversibly suppress sperm production in most men. Though a combination oral birth control pill wouldn't work - the necessary testosterone would get broken down too quickly in the liver - researchers have developed several other delivery methods: monthly injections, creams and twice-a-year synthetic implants into the arm. None of these birth control methods are as convenient or noninvasive as the Pill for women, but they are as safe and as reversible...
...clinical trials. But studies have also shown that 10% to 15% of men don't respond to hormonal treatments at all - a fairly high nonresponder rate. Researchers don't yet know how to explain those failures. One inherent stumbling block is that a male contraceptive must block millions of sperm, as opposed to a single egg. (The Pill had it easy.) Another is race: according to several proof-of-concept studies, Asian men maintained a suppressed sperm count with greater frequency than Caucasians, but researchers still don't know...