There are many reasons as to why the marital rape laws have still not been implemented and criminalised in section of 375 under the Indian Penal Code, which are as follows:

1. According to the common beliefs, the crime of marital rape is quite uncommon, which is in fact not true. The crime of marital rape is very much common, although almost half of these are not reported by women since they tend to remain either unaware about the fact that they have been raped or they would like to remain in their marriage and be far from the societal judgements and stigma.
2. Another reason given for the non-implementation of marital rape laws is the problem of proving marital rape. Given, that marital rape maybe a little difficult to prove since it takes place on an individual level, in a personal space, however there are ways in which a rape can be proved and hence not criminalising marital rape simply on this ground cannot be justified.
3. There are many arguments stating that the implementation of marital rape laws will pave way for wives who are angry or sought to seek revenge can use these laws to their own advantage and thus blame and seek unnecessary redressal using the provisions of such laws. It is important to realise that if proving an actual marital rape is difficult, then proving an untrue marital rape case would be a lot more difficult. Moreover, the court cannot punish any person without ensuring that the facts and evidence provided against him are beyond reasonable doubt. Also if this argument is kept in mind while formulating laws, then no laws will be formulated given they maybe used to the advantage of the person whether woman or man. Thus not criminalising laws for this purpose is non-justifiable. 
4. The last issue which is used as an argument to prevent the formulation of laws related to marital rape is social concern. There is a common belief that formulating such a law or even a provision for the same under section 375 will destroy the trust and belief system that holds marriages together. At this stage it becomes important to realise the fact that if in any marriage, the husband has raped or has coerced the wife into having sexual intercourse with him using force or violence, then such a marriage has already been broken. A provision or law for such a rape would rather help the wife or the women by bringing her out of the mental and physical trauma, allow her to be independent and build life. Moreover, it would also help prevent the wife from suiciding or carrying out any crime in return. 
5. Lastly, the custom of marriage has been prevalent in India since the beginning and since time immemorial, women have been considered subordinate to men in all aspects economic, social, financial and emotional. They have been subject to the doctrine of suppressing the rights of women after marriage. Moreover, the immense poverty, lack of financial support, emotional imbalance, the prejudices of the society as a whole have been constant obstacles which have led to the non-criminalisation of marital rape.