If you have important WhatsApp conversations on your iPhone, it is extremely necessary to backup iPhone WhatsApp messages to avoid losing them, since data loss can easily happen due to accidental deletion, iOS update, factory settings restore, jailbreak, damage, corruption, etc.
You can backup iPhone WhatsApp data with iTunes, but you have no choice to selectively backup the iPhone chat history you want, and you cannot access the backed up WhatsApp messages directly for they are in a proprietary database format. In fact, it is the best choice for you to backup iPhone WhatsApp messages to PC with iPhone Data Recovery, so that you can free view the detailed data at any time and you won't lose them even though you delete them on your device. Below are the details.
With iPhone Data Recovery, you can easily backup all precious WhatsApp chat log to computer in readable formats. This backup software allows you to selectively choose what to back up, freely view all detailed messages, and cause no data loss on iPhone 6/6 Plus/5S/5C/5/4S/4. Download and install it on your Windows 10/8.1/8/7/XP/Vista and do as follows to backup your WhatsApp conversations. For Mac users who run OS X 10.10, Mavericks (10.9), Mountain Lion (10.8), 10.7, 10.6, go to iPhone Data Recovery for Mac.
Since iTunes backs up your iPhone contents into unreadable database and files, if you want to view the data in iTunes, you can do it with iTunes Data Recovery. We have dedicated an article about how to view iTunes backup. You can check it out whenever you need.
Remember that iPhone Data Recovery allows you to backup and restore iPhone WhatsApp messages to PC. Try to learn more about it.