--- title: "13 weeks pregnant: baby the size of a pea pod | PERIOD." description: "13 weeks pregnant: your baby is the size of a pea pod, about 7 cm and 40 g. What happens this week for your baby and in your body." url: https://myperiod.app/en/pregnancy/13-weeks-pregnant lang: en publisher: PERIOD. B.V., Amsterdam --- [Pregnancy week by week](https://myperiod.app/en/pregnancy) # 13 weeks pregnant At 13 weeks you are in month 3 and the first trimester. Your baby is about the size of a pea pod: 7 cm and 40 g. As big as pea pod Length 7 cm Weight 40 g Month 3 Trimester first trimester To go 189 days Averages. Measured crown to rump up to week 20, crown to heel after that. Healthy babies vary a lot. ## Your baby this week Fingerprints are forming. Already one of a kind. ## Your body The second trimester begins; many women get more energy. ## Good to know The baby can swallow and practises with amniotic fluid. ## To sort around these weeks - Your booking appointment and usually a dating scan, which fixes your due date. - Decide when you tell people, and when you tell your employer. [Work out your due date](https://myperiod.app/en/tools/due-date-calculator)[How many weeks pregnant am I?](https://myperiod.app/en/tools/pregnancy-week-calculator) ## Follow your pregnancy week by week In PERIOD. baby you see every week how big your baby is, what is happening and what you can arrange. No ads, and we never sell your data. 4.8 ★★★★★ on the App Store 100,000+ women ## Frequently asked questions ### How many months is 13 weeks pregnant? 13 weeks pregnant falls in month 3 of your pregnancy. ### Which trimester is 13 weeks? At 13 weeks you are in the first trimester. ### How big is a baby at 13 weeks? On average 7 cm, about the size of a pea pod. Healthy babies vary a lot. ### How long to go at 13 weeks? Until your due date (40 weeks): 27 weeks, 189 days. ## [All weeks](https://myperiod.app/en/pregnancy) - [4](https://myperiod.app/en/pregnancy/4-weeks-pregnant) - [5](https://myperiod.app/en/pregnancy/5-weeks-pregnant) - [6](https://myperiod.app/en/pregnancy/6-weeks-pregnant) - [7](https://myperiod.app/en/pregnancy/7-weeks-pregnant) - [8](https://myperiod.app/en/pregnancy/8-weeks-pregnant) - [9](https://myperiod.app/en/pregnancy/9-weeks-pregnant) - [10](https://myperiod.app/en/pregnancy/10-weeks-pregnant) - [11](https://myperiod.app/en/pregnancy/11-weeks-pregnant) - [12](https://myperiod.app/en/pregnancy/12-weeks-pregnant) - [13](https://myperiod.app/en/pregnancy/13-weeks-pregnant) - [14](https://myperiod.app/en/pregnancy/14-weeks-pregnant) - [15](https://myperiod.app/en/pregnancy/15-weeks-pregnant) - [16](https://myperiod.app/en/pregnancy/16-weeks-pregnant) - [17](https://myperiod.app/en/pregnancy/17-weeks-pregnant) - [18](https://myperiod.app/en/pregnancy/18-weeks-pregnant) - [19](https://myperiod.app/en/pregnancy/19-weeks-pregnant) - [20](https://myperiod.app/en/pregnancy/20-weeks-pregnant) - [21](https://myperiod.app/en/pregnancy/21-weeks-pregnant) - [22](https://myperiod.app/en/pregnancy/22-weeks-pregnant) - [23](https://myperiod.app/en/pregnancy/23-weeks-pregnant) - [24](https://myperiod.app/en/pregnancy/24-weeks-pregnant) - [25](https://myperiod.app/en/pregnancy/25-weeks-pregnant) - [26](https://myperiod.app/en/pregnancy/26-weeks-pregnant) - [27](https://myperiod.app/en/pregnancy/27-weeks-pregnant) - [28](https://myperiod.app/en/pregnancy/28-weeks-pregnant) - [29](https://myperiod.app/en/pregnancy/29-weeks-pregnant) - [30](https://myperiod.app/en/pregnancy/30-weeks-pregnant) - [31](https://myperiod.app/en/pregnancy/31-weeks-pregnant) - [32](https://myperiod.app/en/pregnancy/32-weeks-pregnant) - [33](https://myperiod.app/en/pregnancy/33-weeks-pregnant) - [34](https://myperiod.app/en/pregnancy/34-weeks-pregnant) - [35](https://myperiod.app/en/pregnancy/35-weeks-pregnant) - [36](https://myperiod.app/en/pregnancy/36-weeks-pregnant) - [37](https://myperiod.app/en/pregnancy/37-weeks-pregnant) - [38](https://myperiod.app/en/pregnancy/38-weeks-pregnant) - [39](https://myperiod.app/en/pregnancy/39-weeks-pregnant) - [40](https://myperiod.app/en/pregnancy/40-weeks-pregnant) - [41](https://myperiod.app/en/pregnancy/41-weeks-pregnant) - [42](https://myperiod.app/en/pregnancy/42-weeks-pregnant) General information, not medical advice. If in doubt, call your midwife or GP. Sources: WHO fetal growth charts (Kiserud et al., PLoS Med 2017); Robinson and Fleming 1975; NHS, Your pregnancy and baby guide.