How Can You Know The Due Date If You Don't Know Your Last Cycle Start Date

Because I'm wondering Care Providers Seem To Take the due date have a very strict reference. If you're late you get induced, if you're early it's 'high risk'. What If You Were purpose Wrong About the date of your last cycle? You Might end up HAVING Unnecessary interventions. Is your cycle date The Things They Rely on hand, or Do They Consider Other Factors in Determining The due date?