Sotah 11b - Shifra and Puah

Maharal (Gur Aryeh) asks why does the Torah refer to yocheved and miriyam as shifra and puah rather than referring to them by their actual names? He explains that prior to the birth of moshe the torah did not want to give any recognition to his family members, especially his parents, because that would indicate that Moshe's parents were responsible for who he was. Although normally that is the case, that the zechuyos and contributions of the parents form the child and without these specific parents the child will not exist, by Moshe this was not the case, his existence was not dependent on amram and yocheved as his parents. Moshe was already set and destined from the six days of creation to lead the Jews out of mitzrayim. That is why the torah doesn't even mention amram and yocheved when describing moshe's birth.

The Chasam Sofer (Torah Moshe, but i added a lot to his yesod) explains that Pharoh specifically requested of the Jewish women to murder the children, rather than asking the non-jewish midwives because he realized that the Jewish woman are not chayev misah for abortion, whereas the non-jewish woman are chayev misah for abortion. Pharoh wanted them to use the siman of "avnayim" to determine when the labor will begin so that they can be present and then use the siman of which way the child is facing to determine if it is a boy or a girl as the gemara explains, and to abort all the boys before the head comes out while it still has a status of an "u'bar". Pharoh's logic in why they would listen is because normally one is not allowed to commit murder to save their life because "מי יימר דדמא דידך סומק טפי דלמא דמא דהאי גברא סומק טפי", but this would only apply to a murder of a "life". For the goyim even the fetus has the status of "life" since they are chayev misah on abortion, and the sevara of מי יימר וכו would apply equally to murder and abortion. But for the Jewish women the fetus was not considered a full "life" since they are not chayev misah for abortion, therefore they should be able to determine that their lives are more precious than that of the child and abort the fetus to fulfill the command of the king and save their own lives. However, when confronted by Pharoh for not following through with this partial birth abortion, their claim was that by the time the arrived the fetus was fully born כי חיות הנה and they were not allowed to kill a born child even if it would cost them their own lives.