39 Weeks Pregnant

If you are 39 weeks pregnant today, your estimated due date is around .

Calculation method

The day your last period started — not the day it ended.

Cycle length (optional)

Usually 21–35 days. Leave at 28 if unsure.

Your estimated due date, week of pregnancy and trimester will appear here.

39 weeks pregnant: the key facts

TrimesterThird trimester
Month of pregnancyMonth 9 (approximately)
Week of pregnancyWeek 40 (39 weeks completed)
Weeks to the due date1 week
Days since conception (approx.)259 days
Baby’s size (rough comparison)About the size of a small watermelon

What typically happens at 39 weeks

From 39 weeks a pregnancy is considered full term.

The third trimester is about growth and getting ready for birth. Appointments usually become more frequent, and it is a good time to think about your birth preferences and practical preparations. You have reached full term.

Every pregnancy is different, and the timing of tests and appointments depends on your healthcare provider and country. If something worries you — for example bleeding, severe pain, fluid leaking or, later in pregnancy, a change in your baby’s movements — contact your midwife, doctor or maternity unit straight away.

39 weeks pregnant in days and months

39 weeks is 273 days of pregnancy, counted from the first day of the last period, which is 98% of the way through a 40-week pregnancy. In months, 39 weeks is roughly 9.0 calendar months — usually described as month 9 of pregnancy. Because the baby’s age is counted from conception, it is about two weeks younger than the pregnancy: roughly 37 weeks of fetal age.

Your dates if you are 39 weeks pregnant today

Being 39 weeks pregnant today means the first day of your last period was around and conception most likely happened around . Your estimated due date is . For dates based on your actual period, use the calculator above or the main Due Date Calculator.

Other weeks

37 weeks pregnant · 38 weeks pregnant · 40 weeks pregnant · 41 weeks pregnant · full pregnancy timeline

Frequently asked questions

How many months is 39 weeks pregnant?

39 weeks pregnant is roughly month 9 of pregnancy. Months are approximate because a calendar month is about 4.3 weeks.

What trimester is 39 weeks?

The third trimester, which starts at 28 weeks.

When is my due date if I am 39 weeks pregnant?

About 1 week from today. The exact date is shown at the top of this page; for a date based on your last period, use the calculator.

Formulas reviewed and page updated October 6, 2026.