Also written 40+5 or 40w5d
The short answer
40 weeks 5 days = 9 months
At 40 weeks 5 days pregnant you are in your due date week — day 285 of a pregnancy counted as 40 weeks, or 9 months.
Not sure of your exact week and day? The pregnancy week calculator works it out from your last period, due date or conception date.
You have passed the 40-week mark — 40 weeks 5 days is 5 days past 40 weeks. Most babies arrive within two weeks either side of the due date, and your provider will be monitoring more closely and discussing options such as a membrane sweep or induction.
Months of pregnancy are counted in uneven buckets of 4 to 5 weeks, arranged so that the full 40 weeks fits into 9 calendar months. Week 40 sits inside month 9, and it stays there for all seven days of the week — so 40 weeks 0 days and 40 weeks 5 days are both "9 months pregnant".
If you want the strict calendar answer instead, divide by the real length of a month rather than by four: 285 days ÷ 30.4375 days per month = 9.4 calendar months. That figure drifts from the bucket-based month number, which is exactly why your care team sticks to weeks and days.
The days part matters clinically even when the month doesn't. Screening windows, term definitions and induction timing are all set by exact week and day — full term starts at 39 weeks 0 days, not "9 months". See the full weeks to months chart for every week.
Due date week — though only about 1 in 20 babies actually arrives on the estimated date itself. Most come within two weeks on either side.
Read the full week 40 breakdown →
| Week + day | Months pregnant | Days pregnant | Days to go |
|---|---|---|---|
| 40 weeks | about 9 months | 280 | — |
| 40 weeks 1 day | about 9 months | 281 | — |
| 40 weeks 2 days | about 9 months | 282 | — |
| 40 weeks 3 days | about 9 months | 283 | — |
| 40 weeks 4 days | about 9 months | 284 | — |
| 40 weeks 5 days (you) | about 9 months | 285 | — |
| 40 weeks 6 days | about 9 months | 286 | — |
At 40 weeks 5 days pregnant you are in your due date week — day 285 of a pregnancy counted as 40 weeks, or 9 months. Months of pregnancy are counted as uneven 4–5 week buckets so the full 40 weeks fits into 9 calendar months, which is why the extra 5 days doesn't change your month number.
"40+5" is the shorthand your midwife or doctor uses for 40 weeks 5 days — the number before the plus is completed weeks, the number after it is completed days into the current week. You may also see it written 40w5d. Both mean exactly the same thing.
40 weeks 5 days is 285 days, counted from the first day of your last menstrual period (40 × 7 = 280, plus 5). You are now 5 days past the 40-week mark.
40 weeks 5 days is in the third trimester, which runs from 28 weeks 0 days until birth. You are already full term, which starts at 39 weeks 0 days.