As per your query it is understood that a mutual consent divorce is filed and the after filing such case the wife got pregnant from another man and the husband wants to know about what legal action he can take.
The husband can file an appeal in the court to waive off the period of six months which is necessarily given after filing the mutual consent divorce on the grounds that the wife is pregnant from another man.
In the case of Amardeep Singh vs Harveen Kaur, the Bombay High Court waived the six months’ cooling-off period provided under Section 13B of the Hindu Marriage Act, 1955. This was done after it accepted a woman’s plea to dissolve her marriage as she was pregnant by another man whom she intended to marry after the divorce.
The Apex Court finally held that Section 13B (2) was a directory and the Court may consider waiving the cooling-off period.
The husband can make an appeal and deny to pay the maintenance of the child who is born from another person as the husband is not the biological father of that child.
The husband should not think of harassing his wife but to get out of such marriage as soon as possible. It can be a better option for both the parties.
Hope it helps!