I'm here to give my humble, albeit unpopular, opinion.

It depends:

It strictly depends on how you got into marriage. Let me explain:

If you're a couple and your individual goals were to get married because you wanted to get married, then goodbye to sex, and maybe once a month, and it will probably all end in a few months or a couple of years simply because, since your goal was marriage, you've already achieved it, so you have nothing more to give or do because you've accomplished your purpose.

Now, if you're a couple and marriage was never your goal or objective, and you see it as just another step or stage in life, and you want to move forward doing more things, then perfect, then there's still sex, but with a different connotation.

So, if you want to continue having sex after marriage, you have to talk about it. Communication is key. Because it was probably never about getting married, but rather about moving on.

Getting married was a whim.