From a discussion in Book X of Aristotle’s History of Animals on the causes of infertility:
There are various signs by which you can tell that the man is not responsible [for a failure to conceive]; and it is very easy to tell this if he has intercourse with other women and produces children. And it is a sign that they do not keep pace with one another if, although all the conditions described are met, he does not produce children. For it is plain that this alone is the cause; for if the woman too contributes something to the semen and to the process of generation, it is plain that the partners must keep pace with one another. Thus if the man ejaculates quickly and the women with difficulty (for women are for the most part slower), that prevents conception; and that is why partners who do not produce children with one another do produce children when they meet with partners who keep pace with them during intercourse. For if the woman is excited and prepared and has the appropriate thoughts, and the man has previously been pained and has grown cold, they must necessarily then keep pace with one another.
I’m having trouble squaring that passage with Book II, chapter 4 of the Generation of Animals, where Aristotle says that conception is possible even if the female does not take the pleasure in sex that she typically takes.