The science of embryological development isn’t pro life it’s just fact. It is a fact that, as you said, can only strengthen the pro life viewpoint.
Life begins at conception. At conception a new and unique human being is formed.
it may not have legal personhood but it’s still a human being. There’s no stage of life where you are not a human being. You are always the exact same human being from the second of conception to your last dying breath.
Not really a difficult concept in my opinion. - gabbie