What pregnancy week 15 means
Senses are developing. “15 weeks pregnant” means 15 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 13 weeks. Week 15 runs from 15 weeks 0 days to 15 weeks 6 days; on the following day the pregnancy is 16 weeks.
Your baby at 15 weeks
The skeleton continues to harden, and the baby is moving the joints constantly. The eyes are sensitive to light even though the eyelids are still fused.
A common way to picture it: the baby is now about the size of an apple — roughly about 10 cm and about 70 g. These are averages; babies grow at different rates, and ultrasound measurements vary.
Your body at 15 weeks
Some people notice a stuffy nose or nosebleeds, caused by increased blood flow to the mucous membranes. Gums may also bleed more easily when brushing.
Care and appointments around week 15
Second-trimester blood screening (such as the quad screen) is commonly offered between about 15 and 22 weeks if earlier screening was not done.
The timing of tests and appointments differs between countries and care providers. If anything worries you — such as bleeding, severe pain, fluid leaking, fever — contact your midwife, doctor or maternity unit straight away rather than waiting for your next appointment.
Week 15 in your pregnancy timeline
Week 15 is in the second trimester (weeks 14–27) and in pregnancy month 4, which covers roughly weeks 14–17. The third trimester begins in 13 weeks.
| 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 15 weeks 0 days today. For dates based on your own last period, use the calculator above or the main Pregnancy Calculator.
15 weeks pregnant in days and months
15 weeks is 105 days of pregnancy — 38% of a 40-week pregnancy. Counted in calendar months, 15 weeks is about 3.4 months, which is usually described as month 4 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.