All perfect praise be to Allah, The Lord of The Worlds and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions.

The concept of marriage and procreation in Islamic Sharia is based on great objectives and interests such as building strong and pious family which is the cornerstone of settling on earth according to Allah's, The Exalted Sharia as well establishing good and capable individual who can grant and build. In this regard, the Prophet (PBUH) said (What means): "The stronger believer is better and more beloved to Allah than the weak believer, although both are good." [Related by Moslim]. In addition, he said (What means): "Marry women who are beloved (due to their good characteristics), prolific in bearing children, for I shall outnumber the Prophets by you on the Day of Resurrection." [Related by Abu Dawood].

This great objective within family order enable us to realize the importance of the offspring's safety from the latter disease and to make proper measures and precautions which ensure healthy and intact offspring both physically and psychologically.

Thus, there is no harm in making legislation which help in the control of marriage in accordance to the objectives of Sharia as much as possible; especially, the ones pertaining to the restriction of the marriage among ill or carriers of fatal diseases through which they are transmitted to their kids due to their marriage or might be transmitted between the spouses themselves, that's why this kind of marriage might be a main factor in wearing away society as well health institutions due to the huge expenses on medication in this regard. 

Yet, Allah, The Exalted has created a plenty healthy Muslim women whom you can choose from so the patient or the carrier might choose one of the healthy women by which the probability of being afflicted with a disease is eliminated or weaken, and this isn't considered an act to make the lawful unlawful; rather, it is a sort of restricting the lawful for the purpose achieving benefit and warding off corruption. Further, this responsibility lies on the shoulders of people in charge and takes effect after conducting the proper study and imperative deliberations.

As for the ruling of making abortion for afflicted fetus, it is impermissible to conduct this procedure if it was more than 4 months old, but if the fetus was less than 4 months its ruling is stated by the Board of Iftaa in resolution No. (35) as follow: "If it became four months old or more, then aborting it is impermissible, even if it was deformed, in case the doctors determined that it is likely to survive. However, if it jeopardizes the mother`s life, then it is permissible to abort it. Moreover, if it didn`t become four months old, and it was confirmed that its deformity will make its life unstable, then it is permissible to abort it with the consent of both spouses."

Therefore, if the fetus is afflicted with drepanocytic anemia and was less than four months old, then aborting it is permissible. And Allah knows best.