How is the IVF due date calculated?

Question

Accepted Answer

The IVF due date is calculated from the embryo transfer date and the embryo day. Per SART/ASRM standards, a Day 5 blastocyst transfer uses transfer date + 263 days, which is equivalent to LMP + 280 days. Day 3 cleavage transfer uses transfer + 261 days; Day 6 delayed blastocyst uses transfer + 262 days. Unlike the standard due date calculator that uses the last menstrual period, IVF cycles are anchored to the transfer date, making this calculator more accurate for IVF pregnancies. Actual delivery can vary by about ±2 weeks; your obstetrician's ultrasound-based dating takes priority.