Polysomnography is used to diagnose, or rule out, many types of sleep disorders including narcolepsy, idiopathic hypersomnia, periodic limb movement disorder (PLMD), REM behavior disorder, parasomnias, and sleep apnea.
Calculating Due Date: Estimated Due Date. Based on the last menstrual period, the estimated due date is 40 weeks from the first day of the period. This is just an estimate since only about 5% of babies are born on their estimated due date.
Calculation Instructions: 1  Select Gender - Choose male for boys and female for girls. 2  Measure Date - Enter the day the measurement was taken. 3  Due Date - Enter the original due date. Note, this calculator assume 280 days between first day of last menstrual period (LMP) to birth. 4  Enter Head Circumference - distance around the child's head.