Docs/Sources/Pregnancy Due Dates

Pregnancy Due Dates

Calculate pregnancy due dates

OperationalCredits 2 per callp50 200msLifestyle

Overview

Includes pregnancy milestones, percentage completion, and important dates like trimester transitions, perfect for pregnancy tracking and prenatal care applications.

Formula

One function covers the whole catalog: the first argument names the source, the rest are its inputs, and the "field" pair says which single value lands in the cell. Formulas covers the grammar that applies to all of them.

=VERVE("duedatecalculator", A2, "field", "calculation_method")

A2 holds the last_period you are looking up. Drag the formula down and each row resolves on its own.

With literal values

Nothing has to come from a cell — typed values work the same way.

=VERVE("duedatecalculator", "2025-06-01", "field", "calculation_method")

Inputs

Required inputs are positional, in the order below. Everything else is passed as a "name", value pair after them — the same shape as SUMIFS. Premium inputs are accepted on every plan but only take effect on plans that include them.

InputTypeWhere it goesDescription
last_periodRequiredstringargument 2 (A2)First day of last menstrual period (YYYY-MM-DD)
date

What lands in your sheet

The "field" pair is what makes the formula resolve to one cell. Its value is a dot-path from the table below, so swapping it is how you pull a different value — one formula per column.

Seeing everything at once

Drop the "field" pair and the formula returns the whole response instead: two columns, field name on the left and value on the right, spilling from the cell you typed in.

=VERVE("duedatecalculator", A2)
Good for exploring, not for filling down

The second row's table would land on top of the first's, and every cell after the first reads #REF! (#SPILL! in Excel). Keep one per sheet, or name a field, and leave the cells below and to the right empty.

Response fields

Paths are relative to data. Each one is exactly what the "field" pair accepts, so swapping it is how you pull a different value into a cell. On a plan without a Premium field the cell reads #PREMIUM(field) rather than a value, so a locked field never looks like a real answer.

Use as "field"TypeExample cell valueDescription
calculation_methodstringlast_periodMethod used for calculation: last_period or conception_date
last_period_datePremiumstring2024-01-01Estimated first day of last menstrual period
estimated_conception_datePremiumstring2024-01-15Conception date provided as input
due_datestring2024-10-07Estimated delivery date in ISO format
current_progressobject{…}How far along the pregnancy is today, in days and weeks
current_progress.days_pregnantPremiumnumber715Total number of days pregnant
current_progress.weeks_pregnantPremiumnumber102Number of complete weeks of pregnancy
current_progress.days_into_weekPremiumnumber1Additional days beyond complete weeks
current_progress.formattedPremiumstring102 weeks, 1 daysHuman-readable pregnancy duration with weeks and days
current_progress.trimesterPremiumnumber3Current trimester number: 1, 2, or 3
current_progress.percentage_completePremiumnumber255.36Pregnancy completion percentage relative to due date
time_until_dueobject{…}How long until the due date, with a formatted summary
time_until_due.daysPremiumnumber0Complete days remaining until due date
time_until_due.weeksPremiumnumber0Complete weeks remaining until due date
time_until_due.days_extraPremiumnumber0Additional days beyond complete weeks remaining
time_until_due.formattedPremiumstringPast due dateHuman-readable time remaining until delivery
time_until_due.is_overduePremiumbooleantrueWhether pregnancy has passed the due date
upcoming_milestonesPremiumarray[]Array of upcoming pregnancy milestones and dates
important_datesobject{…}Key milestones: the end of each trimester and viability
important_dates.end_first_trimesterPremiumstring2024-04-01Estimated end date of first trimester
important_dates.end_second_trimesterPremiumstring2024-07-08Estimated end date of second trimester
important_dates.full_term_beginsPremiumstring2024-09-16Date when pregnancy reaches full term status
disclaimerstringThis is an estimate only. Due dates can vary. Consult your healthcare provider for medical advice.Medical disclaimer about estimated due dates

Filling a whole column

Both platforms make one batched call for a column rather than one request per cell, and both cost the same — 2 credits per row looked up. How you write it differs, because the two runtimes batch at different points.

Rows 2–100 in one call
=VERVE("duedatecalculator", A2:A100, "field", "calculation_method")

In Google Sheets, give the arguments ranges and the answers spill down from the cell you typed in. Custom functions there run synchronously and in isolation, so dragged cells cannot be coalesced — the range form is how a column becomes one call. The "field" pair is required here: a per-row two-column table has nowhere to spill. Use a full column per input (A2:A100, not A2) — a single-cell reference is read as row 1 only and the rest of the column comes back blank.

In Excel, type the formula once and fill down — no range form and none needed, because its runtime is asynchronous and the add-in coalesces the calls a fill produces into a single batched request. Do not hand VERVE.CALL a range: Excel flattens it into positional arguments, so A2:A100 arrives as a hundred separate arguments and the cell reads #ERR rather than filling.

Either way, column A holds your last_period values and the answers land beside them, one row each, blank rows skipped.

When a cell doesn't fill

A failed lookup returns readable text starting with #ERR rather than a spreadsheet error, because Excel cannot show a custom message on a real error — you would get a bare #VALUE! with no reason. The trade-off is that IFERROR() will not catch it; test with LEFT(cell, 4) = "#ERR" instead. Error handling covers the rest.

Cell readsWhat happened
#ERR Not connectedNo API key saved. Open the side panel and connect your account.
#ERR Replace <name> with a cell or valueA preview formula was copied as-is. Swap the placeholder for a cell reference.
#ERR No "x" in duedatecalculatorAn option name this source does not take. The message lists the ones it does.
#ERR No data point "…"The "field" path is not in the response. Check it against the table above.
#PREMIUM(field)The field exists but your plan does not include it.
#ERR Out of creditsThe cycle's credits are spent. Usage resets on your billing date.

Before the formula works

The add-in reads the API key you saved once in the side panel — the key never goes in the formula, so a shared sheet does not leak it and a collaborator without access simply sees the last calculated values.

  1. Install the add-in for Google Sheets or Excel.
  2. Open the side panel and sign in, or paste a key from your dashboard.
  3. Type the formula above into any cell.

Use cases

Pregnancy Tracking
Build pregnancy tracking applications with accurate due date calculations based on last menstrual period or conception date
Prenatal Care
Calculate gestational age for prenatal care appointments, monitoring fetal development, and scheduling medical tests
Maternity Planning
Create maternity planning tools with delivery date estimates, trimester breakdowns, and important date tracking
Milestone Tracking
Provide pregnancy milestone information with week-by-week pregnancy timeline and key development stages

Other ways to use Pregnancy Due Dates

Set up Pregnancy Due Dates on VerveSheets, or reach the same source a different way. Your VerveSheets account and credits work on all of them — one key, one balance.

Call it as a REST APIOne HTTPS endpoint and an x-api-key header, with SDKs for Node, Python and .NET.APIVerveReference →
Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.VerveKitReference →
Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.VerveContextReference →

More in Lifestyle:

Was this page helpful?