For uncomplicated pregnancies in the United States, most people go off work on disability at 36 weeks. Standard disability after delivery is 6 weeks for a vaginal delivery and 8 weeks for a c-section. There are programs such as Family Medical Leave that can extend the time off. This additional time off is often unpaid.
Each state has different rules for disability. In California we have SDI. This is a disability insurance policy that is automatically deducted from your paycheck. SDI requires that the doctor give a diagnosis code to justify the disability. For example, V22.0 is a routine first pregnancy. For this code the state allows disability to be paid 4 weeks before the due date and 6 weeks after the delivery. To get more time off, a different code will need to be given.
There are reasons that someone will need to be out of work before 4 weeks prior to the due date. Preterm labor, preeclampsia, and hypertension requiring bed rest are all examples of diagnoses that may require more time off work. Discuss with your doctor when you should go off; it will depend on your unique situation.
Some women want to work longer than 36 weeks. It is often safe and reasonable to continue to work until you go into labor if this is your choice. Be aware that in most cases you cannot “bank” the disability. For instance, if you live in California and decide not to go off work until 2 weeks prior to your due date, you cannot use the 2 weeks as extra time after the baby comes. You will still only receive 6 weeks off after delivery if you deliver vaginally.