BabyData pregnancy calculators
UK due date, ovulation, pregnancy weeks and maternity pay calculators. Not medical advice.
Should I use this
Quality & Safety
Based on automated analysis of tool definitions and protocol compliance.
Context Cost
This is the approximate number of tokens consumed each time the server's tools are loaded into a model's context. Higher counts reduce the attention available for other tasks.
Install
One-Click Install
Add this to your `claude_desktop_config.json` file:
{
"mcpServers": {
"pregnancy-calculators": {
"url": "https://babydata.co.uk/mcp"
}
}
}Remote endpoints
https://babydata.co.uk/mcpstreamable-httpWhat it can do
Tool inventory
Tools (4)
🟢calculate_due_date(method, date, embryoAge, asOf)
Estimate a pregnancy due date and current stage using Naegele's rule, from the last menstrual period (LMP), conception date, or an IVF embryo-transfer date. Returns the estimated due date, weeks pregnant now, trimester and weeks remaining. Informational only, not medical advice.
Input Schema
{
"type": "object",
"properties": {
"method": {
"type": "string",
"enum": [
"lmp",
"conception",
"ivf"
],
"description": "Dating method (default lmp)."
},
"date": {
"type": "string",
"description": "The relevant date as YYYY-MM-DD: LMP, conception, or IVF transfer date."
},
"embryoAge": {
"type": "number",
"description": "Embryo age in days at IVF transfer (commonly 3 or 5; default 5)."
},
"asOf": {
"type": "string",
"description": "Reference date YYYY-MM-DD for \"weeks pregnant now\" (default today)."
}
},
"required": [
"date"
],
"additionalProperties": false
}🟢calculate_ovulation(lastPeriod, cycleLength)
Estimate the likely ovulation day, the fertile window and the next period from the first day of the last period and the average cycle length. Informational only.
Input Schema
{
"type": "object",
"properties": {
"lastPeriod": {
"type": "string",
"description": "First day of last period as YYYY-MM-DD."
},
"cycleLength": {
"type": "number",
"description": "Average cycle length in days, 20 to 45 (default 28)."
}
},
"required": [
"lastPeriod"
],
"additionalProperties": false
}⚪pregnancy_weeks(lmp, dueDate, asOf)
Work out how many weeks and days pregnant someone is, the trimester and progress through the 40 weeks, from either the LMP or the due date. Informational only, not medical advice.
Input Schema
{
"type": "object",
"properties": {
"lmp": {
"type": "string",
"description": "First day of last period as YYYY-MM-DD."
},
"dueDate": {
"type": "string",
"description": "Due date as YYYY-MM-DD (LMP is worked back as dueDate minus 280 days)."
},
"asOf": {
"type": "string",
"description": "Reference date YYYY-MM-DD (default today)."
}
},
"additionalProperties": false
}⚪maternity_pay(weeklyEarnings, annualSalary)
Estimate UK Statutory Maternity Pay over the 39 weeks under gov.uk rules: 90% of average weekly earnings for 6 weeks, then the lower of the statutory flat rate or 90%. Uses the 2026-27 gov.uk flat rate of £194.32 a week, which changes each April. Estimate only, not advice.
Input Schema
{
"type": "object",
"properties": {
"weeklyEarnings": {
"type": "number",
"description": "Average weekly earnings before tax (GBP)."
},
"annualSalary": {
"type": "number",
"description": "Annual salary before tax (GBP), converted at /52."
}
},
"additionalProperties": false
}Community
Evidence