Pregnancy Month 4

Overview of month 4

Month 4 covers roughly weeks 14 to 17 and opens the second trimester. Many people find this one of the most comfortable stretches of pregnancy: energy returns, nausea fades and the bump becomes more visible.

Weeks in pregnancy month 4

Week	What typically happens
14 weeks	The second trimester begins; energy often starts to return.
15 weeks	Second-trimester blood screening is commonly offered from now.
16 weeks	Some people notice the first flutters of movement.
17 weeks	Cartilage is turning into bone and fat stores begin.

Your baby in month 4

The baby can make facial expressions, fine lanugo hair covers the skin, and the skeleton keeps hardening. The baby is around 13 cm long by the end of the month and is building the first fat stores.

Your body in month 4

Appetite often improves. Round ligament pain, a stuffy nose, bleeding gums and the first flutters of movement (especially in a second pregnancy) are common.

Care during month 4

Second-trimester blood screening may be offered from about 15 weeks. Visits are commonly every four weeks during this trimester. Schedules vary between countries and providers; your own care team will tell you what applies to you.

Why pregnancy months are approximate

A 40-week pregnancy does not divide evenly into nine calendar months: each calendar month is about 4.3 weeks, so nine months is roughly 39 weeks, and the due date falls a week or so later. Different books and apps therefore group weeks into months slightly differently. This site uses the common grouping in which month 4 spans about weeks 14 to 17. When you talk to a healthcare professional, you will hear weeks and days — for example “15 weeks and 2 days” — because that is far more precise. To see exactly where you are, use the Pregnancy Week Calculator.

Pregnancy weeks to months
Pregnancy month	Weeks pregnant (completed)	Trimester
Month 1	Weeks 1–4	First
Month 2	5 to 8 weeks	First
Month 3	9 to 13 weeks	First
Month 4	14 to 17 weeks	Second
Month 5	18 to 22 weeks	Second
Month 6	23 to 27 weeks	Second
Month 7	28 to 31 weeks	Third
Month 8	32 to 35 weeks	Third
Month 9	36 to 40 weeks	Third

Frequently asked questions

Will I feel the baby move in month 4?

Possibly, especially if you have been pregnant before. Many first-time parents feel the first movements a little later, in month 5.

How many weeks is month 4 of pregnancy?

Month 4 covers roughly weeks 14 to 17 of pregnancy. Different sources group weeks into months slightly differently, which is why weeks are the preferred measure.

Which trimester is pregnancy month 4?

Month 4 is in the second trimester.