1 Corinthians 7:4 (ESV)

4 For the wife does not have authority over her own body, but the husband does. Likewise the husband does not have authority over his own body, but the wife does.

To give one’s spouse his (or her) conjugal rights includes giving one’s body. Again, this goes for both husband and wife. This is not a matter of male authority in the home. Rather, it has everything to do with the one-flesh union between husband and wife.