This version was machine-translated from German and has not been medically reviewed. The authoritative version is the German version.
Estimated due date (EDD) and last menstrual period (LMP)
Convert due date, last menstrual period and gestational age at birth into one another
About this calculator
The remaining values are calculated from the date of birth and one further entry (gestational age at birth, calculated due date or last menstrual period): Due date (280 days after the last menstrual period), gestational age at birth and – back-calculated from the due date – a calculated LMP equivalent (EDD − 280 days) that need not correspond to the actual last menstrual period.
Frequently asked questions
Estimated due date (EDD) and last menstrual period (LMP): What does this calculator compute?
The remaining values are calculated from the date of birth and one further entry (gestational age at birth, calculated due date or last menstrual period): Due date (280 days after the last menstrual period), gestational age at birth and – back-calculated from the due date – a calculated LMP equivalent (EDD − 280 days) that need not correspond to the actual last menstrual period.
Estimated due date (EDD) and last menstrual period (LMP): Which sources is this calculator based on?
Naegele FC; Loytved CAL, Fleming V (ZHAW): Textbook of Obstetrics for Midwives, edition 7, Heidelberg: Mohr 1847, p. 89–90 – cited from Loytved CAL, Fleming V: Naegele's rule revisited (Sexual & Reproductive Healthcare 8:100–101, 2016) (2016); American College of Obstetricians and Gynecologists, American Institute of Ultrasound in Medicine, Society for Maternal–Fetal Medicine: Methods for Estimating the Due Date. Committee Opinion No. 700 (Obstet Gynecol 129:e150–e154) (2017); DGGG, OEGGG, SGGG: S2k guideline Induction of labor (AWMF register number 015-088), as of 12/2020 with addendum 04/2021, version 1.1 – Section on indications for induction of labor, p. 29 (2021); DEGUM, ÖGUM, SGUMGG, DGGG, ÖGG et al.: S2e guideline First-trimester diagnostics and therapy @ 11–13+6 weeks of gestation (AWMF register number 085-002), as of 07/2025 – Recommendation 4.1 (dating by crown-rump length) (2025)