^^^ Great response!I think in the marriage contract, the wife can write if she doesn't want her husband to take another wife.
umm.. actually not like that..!!! she cannot say like "U can never marry a second wife..!!"
Her right is like this- If her husband marries for the second time she can stipulate her right to delegated divorce, she can demand seperation and maintenannce of her and her children and she can also claim Deferred Dower.
Besides In Pakistan and Bangladesh(dont know about India), we have our national legislation and a man who contracts another marriage without permission,
(a)shall pay immediately the amount of dower, whether prompt or deferred and,
(b) on conviction upon complaint be punishable with simple imprisonment which may extend to one year or with fine which may extend to 5000/- or with both.