Does a detectable heartbeat prove personhood scientifically and biblically?

Heartbeat detection simply reveals what God made at conception: a human person (Psalm 139:13–16). Personhood does not begin with a detectable pulse; life begins when God knits the child together at conception. Heartbeat laws only serve to create no protection for people before a heartbeat, implying that it's OK to murder children prior to detection. Justice must guard the preborn from conception, without exceptions.

Additionally, from a biblical standpoint, abortion is an act of murder. So the expect that the very people who are intent upon murdering their own child, or the people who are being paid to murder someone's child would not lie while pretending to look for a heartbeat is naïve at best, and sinister at worst.