No. Sex is proper to the Marriage for the unification of the spouses and an openness to begetting children, even if conception is not likely. As long as the marital act is ordered, per se, to conceiving, it’s all good.
If you can still complete the act in the manner its ordered to, you can still have sex. Impotence (inability to perform) would be a matter needing to abstain from other relations.
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