Allaah has given importance to the caring and maintaining of our flesh and blood since their inception - from the time that a Muslim thinks about getting married. The Messenger ordered every youth to strive towards marriage on the condition that he can accommodate a wife, i.e. he has the ability to fulfill the responsibilities of marriage and the obligations of marital life.
'Alqamah reported: "Once while walking with 'Abdullaah he said: 'We were in the company of the Prophet one time when he said: 'Whoever amongst you is able to accommodate (a wife), should get married, because it is the best means for lowering one's gaze and protecting one's private parts. And whoever is not able to, should observe fasting, for indeed it will restrain his sexual vigor.'"
Thereafter, he ordered us to choose a righteous wife. This is since the Messenger informed us of the effect that a person's immediate family has over him in the narration reported by Abu Salamah bin 'Abdir-Rahmaan who related from Abu Hurairah that the Messenger of Allaah said: "There is no child except that he is born upon true faith (Fitrah), but it is his parents that make him a Jew or a Christian or a Zoroastrian. Just as an animal gives birth to a baby animal that is whole, do you find it mutilated?" Then Abu Hurairah recited:
"...the Fitrah of Allaah which He created mankind upon." [Surah Ar-Room: 30]
Abu Hurairah reported that the Prophet said: "A woman is married for four (reasons): Her wealth, her lineage, her beauty and her religion. So choose the woman with (good) religious qualities, may your hands be covered in dust."
Afterward, he commanded us to observe the reported words of remembrance at the time of intercourse. Ibn 'Abbaas narrated that the Prophet said: "If one of you were to say at the time of having intercourse with his wife: 'In the Name of Allaah, O Allaah, protect us from the Devil and protect what you bestow upon us (of offspring) from the Devil', and then it is ordained that you should have a child (on that occasion), he (i.e. Satan) will not bring harm to him." [Agreed Upon]
And in the wording of Muslim, it states: "If one of them were to say at the time of having intercourse with his wife: 'In the Name of Allaah, O Allaah, protect us from the Devil and protect what you bestow upon us (of offspring) from the Devil', and then He ordains that the couple should have a child in that encounter, no Devil will be able to bring harm to him ever." [Agreed Upon]
Then he commanded us to safeguard the fetus and forbade us from aborting it. 'Aa'ishah narrated from Judaamah bint Wahb, the sister of 'Ukkaashah that she said: "I was present in the company of Allaah's Messenger along with some people when he said: 'I intended to prohibit al-gheelah,9 but I examined the Romans and the Persians and found that they feed their children breast milk (from pregnant women) and that it doesn't harm their children at all.' Then they asked him about al-'azl,10 so Allaah's Messenger said: 'That is the invisible form of burying newborns alive.' Then he recited: 'And when the newborn female that was buried alive is asked...'"
So if the Prophet hated al-'azl and called it the invisible form of burying newborns alive, then abortion takes all the more precedence.
9 Translator's Note: Gheelah is when a man has intercourse with his wife while she is in a state of breastfeeding. It is also said tat it means milk from a woman who is pregnant and breastfeeding.
10 Translator's Note: Al-'Azl is the act of a man pulling out during intercourse so as to not get his wife pregnant. It can be translated as coitus interuptus.