Skip to content
Little Us
Try it free

Conceived in September: when is the baby due?

A baby conceived in September is due between 25 May and 23 June of the following year.

That is 38 weeks (266 days) after conception: a pregnancy is counted as 40 weeks from the first day of the last period, about two weeks before conception.

Calculate from
days

Usually 28 days. Count from the first day of one period to the first day of the next.

Calculated on your device. Nothing is sent.

Estimated due date

Enter a date to see your estimated due date.

Not medical advice. Every pregnancy is different: ask your midwife or doctor about yours.

Due date for each day in September

Due date for a conception on each day in September
ConceptionDue date
1 September25 May
2 September26 May
3 September27 May
4 September28 May
5 September29 May
6 September30 May
7 September31 May
8 September1 June
9 September2 June
10 September3 June
11 September4 June
12 September5 June
13 September6 June
14 September7 June
15 September8 June
16 September9 June
17 September10 June
18 September11 June
19 September12 June
20 September13 June
21 September14 June
22 September15 June
23 September16 June
24 September17 June
25 September18 June
26 September19 June
27 September20 June
28 September21 June
29 September22 June
30 September23 June

In a leap year, the date moves by one day when 29 February falls between conception and the due date.

Frequently asked questions

If we conceived in September, when is the baby due?

A baby conceived in September is due between 25 May and 23 June of the following year. The table on this page gives the due date for each day of conception, and the calculator works it out from your own date.

Why is the due date 40 weeks if the baby was conceived 38 weeks before?

Pregnancy is counted from the first day of the last period, about two weeks before ovulation and conception. So the 40 weeks include two weeks before the baby was conceived.

Will the baby come on the due date?

Probably not exactly. Only about 4% of babies are born on their due date, and most arrive in the two weeks before or after it. An early scan gives the most reliable date.