What pregnancy week 27 means
Last week of the second trimester. “27 weeks pregnant” means 27 weeks have passed since the first day of the last menstrual period — the standard way pregnancy is dated. Conception usually happened about two weeks after that date, so the baby’s own age (fetal age) is roughly 25 weeks. Week 27 runs from 27 weeks 0 days to 27 weeks 6 days; on the following day the pregnancy is 28 weeks.
Your baby at 27 weeks
The baby has regular cycles of sleep and wakefulness and may respond to familiar voices. The brain is very active, and the lungs continue to mature.
A common way to picture it: the baby is now about the size of a head of lettuce — roughly about 36.6 cm and about 875 g. These are averages; babies grow at different rates, and ultrasound measurements vary.
Your body at 27 weeks
This is the last week of the second trimester. Restless legs, swollen feet and mild hand tingling are all common as fluid levels rise.
Care and appointments around week 27
If you were offered the glucose screening test and have not had it yet, it is usually completed by 28 weeks.
The timing of tests and appointments differs between countries and care providers. If anything worries you — such as bleeding, severe pain, fluid leaking, fever, or a change in your baby’s movements — contact your midwife, doctor or maternity unit straight away rather than waiting for your next appointment.
Week 27 in your pregnancy timeline
Week 27 is in the second trimester (weeks 14–27) and in pregnancy month 6, which covers roughly weeks 23–27. The third trimester begins in 1 week.
| Pregnancy start (first day of last period) | |
|---|---|
| Estimated conception | |
| Third trimester begins (28 weeks) | |
| Full term (39 weeks) | |
| Estimated due date (40 weeks) |
Dates assume you are exactly 27 weeks 0 days today. For dates based on your own last period, use the calculator above or the main Pregnancy Calculator.
27 weeks pregnant in days and months
27 weeks is 189 days of pregnancy — 68% of a 40-week pregnancy. Counted in calendar months, 27 weeks is about 6.2 months, which is usually described as month 6 of pregnancy. Months are only a rough grouping; healthcare professionals almost always talk in weeks and days because they are more precise. See Pregnancy Month Calculator for how weeks map to months.