From time to time I've read "scholars" opine that people in OT times (or primitive people generally) didn't think the mother made a constitutive contribution in procreation. She was just an incubator. Sometimes they describe it like preformationism, where the man injects homunculi into the woman.
Now, for all I know, there were ancient people who thought in those terms. However, I'm skeptical about imputing that to ancient people or primitive people in general. It doesn't require a knowledge of modern embryology to sense holes in that theory. The evidence available to prescientific people made that theory dubious.
i) You don't have to be terribly observant to notice that family resemblance isn't confined to fathers and their offspring. Kids bear a resemblance to the mother as well as the father. Sometimes kids resemble one parent more than another.
I imagine that this even functioned as a prescientific maternity or paternity test. If, however, the mother was thought to make no positive contribution to the constitution of the child, why would it look like her at all?
Jews were very concerned with maternity, paternity, and heredity (i.e. legitimate heirs). So that's something they'd pay attention to.
ii) If men were thought to make the sole constitutive contribution in procreation, how could they beget females as well as males? Wouldn't you expect them to beget a version of themselves, what was most like them, if they alone made the constitutive contribution in sexual reproduction? After their kind (i.e. male=male)?
iii) Babies don't look like miniature adults. In addition, primitive people had the sad experience of miscarriage. And preemies look even less like miniature adults.
iv) Finally, if ancient people ate bird eggs, that would acquaint them with stages of gestation. They'd find wild eggs at different stages of gestation. And the domestication of chickens antedates OT times.
If they drew analogies between that and human pregnancy, it's inconsistent with preformationism.
I'm not suggesting that everyone wondered about these things. But the ancient world had its share of attentive, inquisitive people.