Obstetrics
11 calculators
Pregnancy dating, estimated fetal weight, pre-eclampsia criteria, obstetric haemorrhage estimation, and perinatal screening.
Related Categories
EDD
Estimates the expected date of delivery from the last menstrual period.
Obstetrics & GynecologyGestational Age
Estimates gestational age from weeks and days.
Obstetrics & GynecologyBishop Score
Scores cervical readiness for induction of labor (Bishop 1964). Five components (dilatation, effacement, station, consistency, position) are each scored 0–3 (or 0–2) and summed to a total of 0–13; higher scores predict a higher likelihood of successful induction and vaginal delivery.
Obstetrics & GynecologyBiophysical Profile (BPP)
Scores fetal well-being (Manning 1980) from five components — fetal breathing, gross body movement, fetal tone, amniotic fluid volume, and (in the full BPP) a non-stress test — each scored 0 or 2 for a total of 0–10. Higher scores indicate reassuring fetal status; lower scores identify fetuses at risk who warrant delivery planning.
Obstetrics & GynecologyHELLP Syndrome Criteria (Tennessee)
Assesses the HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets) using the Tennessee (Sibai) diagnostic criteria: hemolysis (LDH ≥ 600 U/L or schistocytes/low haptoglobin), AST ≥ 70 U/L, and platelets < 100,000/µL. HELLP is a severe form of preeclampsia with substantial maternal and fetal risk.
Obstetrics & GynecologyHadlock Estimated Fetal Weight
Estimates fetal weight from four standard ultrasound biometric measurements (BPD, head circumference, abdominal circumference, and femur length) using the Hadlock four-parameter formula (1985). Output is the estimated fetal weight in grams, with the characteristic ±1 SD error of approximately 7.5%.
Obstetrics & GynecologyPreeclampsia Criteria (ACOG 2020)
Assesses the diagnostic criteria for preeclampsia and the presence of severe features using ACOG Practice Bulletin No. 222 (2020): hypertension after 20 weeks with proteinuria or end-organ dysfunction, with severe features including BP ≥ 160/110, thrombocytopenia, renal insufficiency, liver involvement, pulmonary edema, and cerebral/visual symptoms.
Obstetrics & GynecologyGestational Weight Gain (IOM 2009)
Provides the Institute of Medicine (IOM/NRC 2009) recommended total gestational weight gain and second/third-trimester rate based on pre-pregnancy body mass index (BMI). Categories: underweight (< 18.5), normal (18.5–24.9), overweight (25–29.9), and obese (≥ 30).
Obstetrics & GynecologyMagnesium Sulfate Dosing (Preeclampsia/Eclampsia)
Calculates the total 24-hour magnesium sulfate dose for seizure prophylaxis in preeclampsia with severe features or eclampsia using standard intravenous regimens (ACOG 2020): a 4–6 g IV loading dose over 20–30 minutes followed by a 1–2 g/hour maintenance infusion.
Obstetrics & GynecologyEstimated Blood Loss (Obstetric)
Estimates intraoperative blood loss in obstetrics by two methods: gravimetric (weighed sponges/drapes, 1 g ≈ 1 mL blood) and hematocrit-based (EBL = estimated blood volume × (pre-Hct − post-Hct)/pre-Hct, using a pregnancy blood volume of approximately 85 mL/kg). Postpartum hemorrhage is defined as cumulative blood loss ≥ 1000 mL within 24 hours.
Obstetrics & GynecologyEdinburgh Postnatal Depression Scale (EPDS)
Screens for postpartum (and antenatal) depression using the 10-item Edinburgh Postnatal Depression Scale (Cox 1987). Each item is scored 0–3 for a total of 0–30. A total ≥ 10 (or ≥ 13 in some settings) is screen-positive, and any positive response on item 10 (self-harm) requires immediate evaluation.
Obstetrics & Gynecology