When I read this verse in Jeremiah I was in awe. This verse opened my eyes to our Father's deep love for all his children not just when they pop out but when they are tiny. It also meant that we cannot forget that the beginning of life is happening in a mother's womb and that at each step of its 'knitting' it's precious. 
In Psalm 139 13-14 The Psalmist reminds us that each baby is wonderfully made. 
What do scientists make of those amazing verses? According to Dr. Alfred M. Bongiovanni, professor of obstetrics at the University of Pennsylvania, 'human life begins at the time of conception. I submit that human life is present throughout this entire sequence from conception to adulthood and that any interruption at any point throughout this time constitutes a termination of human life.” 
Speaking of the early stages of a child’s development in the womb, Professor Bongiovanni says, “I am no more prepared to say that these early stages represent an incomplete human being than I would be to say that the child prior to the dramatic effects of puberty is not a human being. This is human life at every stage.”
Also Dr. Jerome LeJeune, genetics professor at the University of Descartes in Paris, states, “after fertilization has taken place a new human being has come into being.” He says this “is no longer a matter of taste or opinion. Each individual has a very neat beginning, at conception.
Professor Micheline Matthews-Roth of Harvard University Medical School argues, “It is scientifically correct to say that an individual human life begins at conception.”
To conclude, I share these verses found in the Book of Job, ch 10 v 8:12 when Job is in utter adversity and rightly worried about his future! 
“Your hands shaped me and made me.

    Will you now turn and destroy me?

Remember that you molded me like clay.

    Will you now turn me to dust again?


Did you not pour me out like milk

    and curdle me like cheese,


clothe me with skin and flesh

    and knit me together with bones and sinews?


You gave me life and showed me kindness,

    and in your providence watched over my spirit.