Estimate survival outcomes based on gestational age statistics.
Yes
No
Estimated Survival Rate:
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Survival Without Major Morbidity:
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Disclaimer: This calculator provides estimates based on general population data (NICHD/Vermont Oxford Network benchmarks). Individual outcomes vary based on sex, plurality, and clinical setting. Consult a neonatologist for personalized medical advice.
Understanding Neonatal Survival Rates
The "limit of viability" has shifted significantly over the last decade due to advancements in neonatal intensive care (NICU). Generally, infants born at 22 weeks are considered at the threshold of viability, while those born after 28 weeks have excellent survival prospects in modern facilities.
Key Factors Influencing Outcomes
Gestational Age: Every day spent in utero significantly increases the chances of survival and reduces the risk of long-term disability between 22 and 26 weeks.
Antenatal Steroids: Administering corticosteroids to the mother before delivery helps mature the infant's lungs and reduces the risk of brain bleeds (IVH).
Birth Weight: While gestational age is the primary predictor, infants who are "small for gestational age" may face additional challenges.
Biological Sex: Statistically, female premature infants tend to have slightly better survival rates than males at the same gestational age.
Statistical Milestones
Below are typical benchmarks for survival in tertiary care centers:
Week
Approx. Survival
Morbidity Risk
23 Weeks
25% – 50%
High
25 Weeks
75% – 85%
Moderate
28 Weeks
90% – 95%
Low
32 Weeks
>98%
Very Low
function calculateNeonatalStats() {
var weeks = parseInt(document.getElementById('gestWeeks').value);
var days = parseInt(document.getElementById('gestDays').value) || 0;
var weight = parseInt(document.getElementById('birthWeight').value) || 0;
var steroids = document.getElementById('steroids').value;
var resultDiv = document.getElementById('neonatalResult');
var survivalText = document.getElementById('survivalRate');
var morbidityText = document.getElementById('morbidityRate');
var statusText = document.getElementById('statusMessage');
if (isNaN(weeks) || weeks < 20) {
alert("Please enter a valid gestational age (minimum 22 weeks for survival data).");
return;
}
// Logic based on NICHD benchmarks (simplified average probabilities)
var survival = 0;
var healthySurvival = 0;
var note = "";
// Data points representing % survival and % survival without major disability
if (weeks = 29 && weeks = 32 && weeks = 34) {
survival = 99;
healthySurvival = 97;
}
// Adjustments for Steroids (+5-10% in low survival brackets)
if (steroids === "yes" && weeks < 30) {
survival += 5;
healthySurvival += 5;
}
// Adjustment for weight (Low birth weight for age reduces survival)
// Average at 24 weeks is ~600g. If 0 && weight 22) {
survival -= 10;
healthySurvival -= 5;
}
// Cap percentages
if (survival > 99) survival = 99;
if (survival 98) healthySurvival = 98;
if (healthySurvival < 1) healthySurvival = 1;
// Display results
resultDiv.style.display = "block";
survivalText.innerHTML = survival + "%";
morbidityText.innerHTML = healthySurvival + "%";
if (note !== "") {
statusText.innerHTML = note;
} else {
statusText.innerHTML = "Estimated for " + weeks + " weeks and " + days + " days.";
}
// Scroll to result
resultDiv.scrollIntoView({ behavior: 'smooth', block: 'nearest' });
}