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Fathers may carry traces of their childhood trauma in their sperm cells, a new study finds. The new research, published Jan. 3 in the journal Molecular Psychiatry, looked at the "epigenetics" of ...

When ejaculation takes place inside the vagina, the sperm swim through the cervix into the uterus. If an egg is waiting, they might fertilise it and when that happens, the cells begin to divide ...

Based on these observations, he asserted that, though it was different in its segregation into sperm cells ... male and female cells, one pair in the males was different in size.