_id

683a15f3c782e11e38d1b0ba

id

423

title

Pregnancy Due Dates Calculator

full_title

Pregnancy Due Dates Calculator

short_title

Pregnancy Due Dates

med_description

Calculates pregnancy dates from last period, gestational age, or date of conception.

short_description

From LMP, EGA, or date of conception.

slug

pregnancy-due-dates-calculator

description

The Pregnancy Due Dates Calculator Calculates pregnancy dates, forward from last period or backward from due date.

keywords

pregnancy due date, preg calc, pregnancy due date calc, pregnancy weeks, lnmp calc, lnmp preg calc, lnmp pregnancy calc, lmp calculator, lmp pregnancy, lmp pregnancy calculator, pregnancy calculator, precnancy calc

complaint

[ "Abdominal Pain" ]

formula

Estimated gestational age (EGA) = time since 1stday of last menstrual period (LMP) Estimated date of conception (EDC) = two weeks* since 1stday of LMP Estimated due date (EDD) = 1stday of LMP + 40 weeks* (Naegele's Rule) *Assumes 28 day cycle. If cycle is longer than 28 days, this calculator adds the number of days more than 28 to obtain EDD. Example: if cycle length is 35 days, add 7 days (= 35 – 28) to 40 weeks.

evidence

measurements

[ { "name": "cyclelength", "unit": "cyclelength", "error_min": "7", "error_max": "63", "warn_min": "7", "warn_max": "63", "conversion": "1", "normal_max_si": "0", "normal_max_us": "0", "normal_min_si": "0", "normal_min_us": "0", "units_si": "days", "units_us": "days" }, { "name": "", "unit": "date", "error_min": "0", "error_max": "0", "warn_min": "0", "warn_max": "0", "conversion": "", "normal_max_si": "0", "normal_max_us": "0", "normal_min_si": "0", "normal_min_us": "0", "units_si": "", "units_us": "undefined" }, { "name": "Gestational Age", "unit": "gestational_age", "error_min": "0", "error_max": "0", "warn_min": "0", "warn_max": "0", "conversion": "0", "normal_max_si": "0", "normal_max_us": "0", "normal_min_si": "0", "normal_min_us": "0", "units_si": "", "units_us": "" } ]

information

refrences

{ "Clinical Practice Guidelines": [ { "href": "https://www.acog.org/Clinical-Guidance-and-Publications/Committee-Opinions/Committee-on-Obstetric-Practice/Methods-for-Estimating-the-Due-Date?IsMobileSet=false#6", "text": "Methods for estimating the due date. Committee Opinion No. 700. American College of Obstetricians and Gynecologists. Obstet Gynecol 2017;129:e150–4." } ], "Manufacturer Website": [], "Original/Primary Reference": [], "Other References": [ { "href": "https://www.ncbi.nlm.nih.gov/pubmed/26171896", "text": "Whitworth M, Bricker L, Mullan C. Ultrasound for fetal assessment in early pregnancy. Cochrane Database Syst Rev. 2015;(7):CD007058." }, { "href": "https://www.ncbi.nlm.nih.gov/pubmed/9579429", "text": "Chervenak FA, Skupski DW, Romero R, et al: How accurate is fetal biometry in the assessment of fetal age? Am J Obstet Gynecol 1998; 178:678." } ], "Outcomes": [], "Validation": [], "Validations": [] }

pearls

According to ACOG, ultrasound measurement in the first trimester (up to and including 13 6/7 weeks of gestation) is the most accurate method to establish or confirm gestational age.

usecase

Patients who are pregnant or may be pregnant.

reasons

Accurate estimates of gestational age may positively affect pregnancy outcomes, including lower risk of post-term induction and earlier detection of multiple gestations (Whitworth 2015).

next_advice

Use to track and estimate pregnancy.

next_actions

next_management

diseases

[ "Pregnancy" ]

input_schema

[ { "conditionality": "", "default": 28, "fhir_rules": null, "inct": null, "label_en": "Cycle length", "name": "cyclelength", "optional": false, "tips_en": "", "type": "textbox", "unit": "cyclelength" }, { "conditionality": "", "default": null, "label_en": "Dates to enter", "mdcalc_info_concept": null, "name": "date_type", "option_fhir_rules": null, "optional": false, "options": [ { "label": "Last menstrual period", "value": 0 }, { "label": "Estimated gestational age (EGA) as of today", "value": 1 }, { "label": "EGA as of another date", "value": 3 }, { "label": "Estimated date of conception", "value": 4 }, { "label": "Estimated due date", "value": 2 } ], "show_points": false, "tips_en": "\"Last menstrual period\" should be first day of LMP; EGA on other date can be taken from a past ultrasound", "type": "radio" }, { "conditionality": "date_type == 0 || date_type == 2 || date_type == 4", "default": null, "fhir_rules": null, "inct": null, "label_en": "Date", "name": "date", "optional": false, "tips_en": "", "type": "textbox", "unit": "date" }, { "conditionality": "date_type == 3", "default": null, "fhir_rules": null, "inct": null, "label_en": "Date of EGA (e.g. date of ultrasound)", "name": "date2", "optional": false, "tips_en": "", "type": "textbox", "unit": "date" }, { "conditionality": "date_type == 1 || date_type == 3", "default": null, "fhir_rules": null, "inct": null, "label_en": "EGA", "name": "gestational_age", "optional": false, "tips_en": "Format: e.g. 7w3d", "type": "textbox", "unit": "gestational_age" } ]

instructions

• Enter date of last menstrual period, gestational age (on today's date or other ultrasound date), date of conception, OR estimated due date to estimate the other dates.
• Only EDD is affected by cycle length ≠28 days when calculating from LMP, EGA, and EDC.
• When starting with EDD, all results change depending on cycle length.

published

2022-04-21T20:29:42.492Z

purpose

[ "Formula" ]

search_terms

[ "preggers", "edd", "preg wheel", "pregnancy wheel", "edc", "pregnant" ]

seo

{ "keywords_en": "pregnancy due date, preg calc, pregnancy due date calc, pregnancy weeks, lnmp calc, lnmp preg calc, lnmp pregnancy calc, lmp calculator, lmp pregnancy, lmp pregnancy calculator, pregnancy calculator, precnancy calc", "meta_description_en": "The Pregnancy Due Dates Calculator Calculates pregnancy dates, forward from last period or backward from due date." }

specialty

[ "Emergency Medicine", "Family Practice", "OB-Gyn", "Pediatrics", "Primary Care" ]

departments

[ "Reproductive" ]

tags

[]

version_number

1

versions

[]

related

[ { "calcId": 10433, "short_title_en": "VBAC (MFMU)", "slug": "vaginal-birth-after-cesarean-vbac" }, { "calcId": 3320, "short_title_en": "Bishop Score", "slug": "bishop-score-vaginal-delivery-induction-labor" }, { "calcId": 3937, "short_title_en": "BWH Egg Freezing Counseling Tool", "slug": "bwh-egg-freezing-counseling-tool-efct" } ]

ismed

false

section

[ "whenToUseViewed", "pearlsPitfallsViewed", "whyUseViewed", "nextStepsViewed", "evidenceViewed" ]

cleaned_departments

[ "gynecology" ]

cleaned_use

[ "Patients who are pregnant or may be pregnant." ]

pub

false