no. 1835 for the year 2008 which includes the following:
In France, a woman takes her husband's last name. What is the stance of religion on this? Is a Muslim blameworthy for doing this?
 

It is the cultural norm in Western countries for an unmarried woman to go by her maiden name and for a married woman to adopt her husband's family and prefix it with the titles 'Mrs', 'madam', or the like to indicate her marital status. This western custom is equivalent to our custom of saying: 'So-and-so is married to a man from such-and-such a family'. In western culture, this practice is a kind of identification that does not involve deception in familial relationships.

The purpose of identification may be due to a variety of reasons such as loyalty, such as the case in the name 'Ikrima mawla Ibn 'Abbas; profession, such as in 'Al-Ghazali'; or a title or nickname such as in' Al-A'ra'j, 'al-Jahidh', and 'Abu Mohammed al-A'mash'. A person may also be attributed to his mother though his father may be known such as in the name 'Isma'il ibn 'Ulayya'. Furthermore, a wife may even be attributed to her husband; the Qur`an mentions a few examples such as:
The wife of Noah and the wife of Lut. [At-Tahrim, 10]
The wife of Pharaoh. [At-Tahrim, 11]
Sa'id al-Khudri (may Allah be pleased with him) reported that Zeinab, Ibn Mas'ud's wife (may Allah be pleased with them both), asked for permission to meet the Prophet . He was told, "O Messenger of Allah! Zeinab asks for permission to meet you."
The Prophet asked, "Which Zeinab?"
He was told, "Ibn Mas'ud's wife."
The Prophet replied, "Allow her to enter." And so they did [Bukhari and Muslim].

Islamic law forbids attributing a person to other than his father with any designation or word implying a genealogical affiliation although affiliation and identification in their general sense are not prohibited. In some places or situations, various forms of identification may become so prevalent that they are established as a custom. There is no harm in this provided it does not lead to lineage confusion that is rejected in Islamic law i.e. paternal attribution to other than a person's father by using a patronym or its equivalent. Moreover, adopting a husband's family name is not from among the imitations considered objectionable in Islamic law. Imitation is only objectionable if the imitated act is prohibited in itself or if the doer intends to imitate a disbeliever. In the absence of any these two conditions, the doer is not blameworthy. This is evidenced by Jaber Ibn 'Abdullah's report in which he said, "The Messenger of Allah was ill so he led us in prayer while seated. He looked behind him and saw us standing, so gestured to us to sit down. After making the closing salutations, he said, 'You were about to do an act similar to that of the Persians and Romans. They stand before their kings while their kings remain seated. Do not do this but follow the actions of your imams; if they offer prayers while standing, do likewise and if they offer prayers while seated, pray in that position' " [Recorded in the Sahih of Muslim (624)]. In the Arabic language, when the verb 'kada' which means 'about to' occurs in the affirmative, it denotes negation. Although the Companions did remain standing while Prophet Mohammed remained seated, they did not intend to imitate the Persians or Romans and therefore were not described as imitators. For this reason, Ibn Nujaym, the Hanafi scholar, wrote in Al-Bahr Ar-Ra` iq (2/11): "Know that imitating the people of the Book is not disliked in every aspect for we eat and drink as they do. What is forbidden is deliberately imitating them and their reprehensible acts."

A wife adopting her husband's family name
There is nothing in the practice of a wife adopting her husband's family name that refutes parental attribution to her father; it is only for the purpose of identification as previously mentioned. The equivocal prohibition was mainly due to the widespread omission of the patronym 'ibn' linking a person's name to his father's. Although it is possible to drop these connecting terms from names due to overuse and to keep them short, this has created confusion in compound names and others that are not intended to show paternal attribution. Official bodies abolished the use of compound names because the individual components of the name may imply paternal affiliation. Societies which formerly used the patronym 'ibn' but in which its omission has become the norm, do not allow a woman to take her husband's name as this will lead to lineage confusion. The case differs in other cultures where a wife takes her husband's family name and prefixes titles such as 'Mrs.' 'madam' etc... that clearly establish the relationship between them. In such cultures, it is permissible to adopt this custom provided it does not contravene the principles of Islamic law.
Islamic law takes customs into account provided they are consistent with it. The legal maxim states "Custom is an arbitrator". Islamic law does not call upon Muslims to defy or deliberately contravene customs; rather, it encourages Muslims not to alienate themselves from the societies they live in but rather assimilate themselves into them. This makes it possible for them to co-exist with members of the society they live in and call them to the true word of Allah without clashing or engaging in contrived disputes. All of this must be compatible with the principles of Islamic law. 

Allah the Almighty knows best.