Tracking your baby’s growth during pregnancy is both exciting and reassuring. A fetal growth chart gives you an idea of how your baby is developing each week in terms of length and weight. Keep in mind that every baby grows at their own pace, so these measurements are estimates. Here's a guide to fetal growth, broken down by trimester.

First Trimester: Weeks 1-13

During the first trimester, your baby grows rapidly from a cluster of cells to a recognizable fetus. Although growth is significant, the baby is still tiny.

• Week 4: Your baby is around the size of a poppy seed, about 0.1 inch long, and weighs almost nothing.

• Week 8: At this stage, the baby is about the size of a raspberry—around 0.6 inches long and weighing about 0.04 ounces.

• Week 12: By the end of the first trimester, the baby is roughly the size of a plum, measuring about 2.1 inches long and weighing around 0.5 ounces.

Second Trimester: Weeks 14-26

The second trimester is known as the growth phase. Your baby will significantly increase in size, and this is the time when most moms feel the first kicks!

• Week 16: Baby is about the size of an avocado, measuring around 4.6 inches and weighing about 3.5 ounces.

• Week 20: Halfway through pregnancy, your baby is the size of a banana, approximately 6.5 inches long from head to rump, and weighs around 10.5 ounces.

• Week 24: At 24 weeks, your baby is about the size of an ear of corn, measuring 12 inches long and weighing around 1.3 pounds.

Third Trimester: Weeks 27-40

In the third trimester, your baby gains the majority of their weight and prepares for life outside the womb.

• Week 28: Your baby is around 14.8 inches long and weighs 2.2 pounds, about the size of a large eggplant.

• Week 32: Now about the size of a squash, your baby is 16.7 inches long and weighs 3.75 pounds.

• Week 36: At this stage, your baby is about the size of a honeydew melon, measuring approximately 18.7 inches long and weighing about 5.8 pounds.

• Week 40: Full-term! Your baby is around 20 inches long and weighs about 7.6 pounds, about the size of a small pumpkin.

Understanding Variations

While these measurements offer a general guide, it’s important to remember that every baby grows at their own rate. Ultrasound measurements and growth scans can give you more personalized information about your baby’s development. Some factors, like genetics and maternal health, can influence growth patterns. If
your baby’s measurements fall outside these ranges, don’t worry—your healthcare provider will monitor their growth closely to ensure everything is progressing as it should.

Watching your baby grow is one of the most thrilling parts of pregnancy. This week-by-week guide to fetal length and weight gives you an idea of what to expect as your baby develops. Remember to enjoy the journey, and know that both you and your baby are doing amazing work!