McDougal said Trump did not use condoms with her, either. (vox.com)
So using condoms with another type of birth control (like the implant, IUD, or pill) gives you backup protection in case either method fails. (plannedparenthood.org)
The five risks at Wave 2 were have not used a condom in past year (4.3 %), drinking during most recent sex (10.7 %), using drugs during most recent sex (7.4 %), sex for drugs or money (3.5 %), and ever had anal sex (15.2 %). (academic.oup.com)