What implication does prenuptial agreement in a family-based immigration petition?

It is important to note that the petitioner has the responsibility to prove to the satisfaction of the adjudicator in USCIS that they entered into the marriage for love, not solely for obtaining immigration benefit, green card, K-visa etc. USCIS officers expect proof of commingled assets including jointly held and actively used bank accounts, CDs, and stocks, housing held in joint tenancy, joint car loans and mortgages, and joint health, life, and car insurance. Therefore, the couples that keeps their financial lives primarily separate with a prenuptial agreement may have a much tougher case to make. 

Marital and prenuptial agreements may also muck up the waters with potentially compromising provisions to the immigrant that could appear as if there is a financial arrangement in exchange for the U.S. citizen’s compliance with the immigration process 

Often time, in the event of lacking commingled fund,  marital and prenuptial agreements have been used by the petitioning U.S. citizen spouses as proof of the immigrant’s intent to marry only for a green card (permanent residency status) if the US citizen spouse to maintain control throughout the immigration process and especially, the finances.  For this reason and due to the fact that these agreements are naturally suspect by immigration, they must be carefully drafted. Both parties should always consult a family lawyer and the immigrant should consult an immigration lawyer in addition before signing any kind of prenuptial agreement.