From the Guidelines
The height of the uterus, also known as fundal height, increases predictably throughout pregnancy, with the fundus becoming palpable above the pubic symphysis at around 12 weeks, reaching the umbilicus by 20 weeks, and corresponding to gestational age in weeks (with a margin of ±2 cm considered normal) between 16 and 36 weeks of gestation 1.
Key Points to Consider
- In early pregnancy (weeks 1-12), the uterus remains within the pelvis and is not typically palpable above the pubic symphysis.
- Around 12 weeks, the fundus becomes palpable just above the pubic symphysis.
- By 16 weeks, the fundus reaches halfway between the pubic symphysis and umbilicus.
- At 20 weeks, the fundus is typically at the level of the umbilicus.
- After this point, fundal height in centimeters roughly corresponds to gestational age in weeks (with a margin of ±2 cm considered normal).
- By 36 weeks, the fundus reaches the xiphoid process, and then may drop slightly in the final weeks as the fetal head engages in the pelvis.
Clinical Application
- This measurement helps clinicians track fetal growth, with measurements consistently smaller or larger than expected potentially indicating growth restriction, macrosomia, abnormal fetal position, multiple gestation, or incorrect dating.
- Regular fundal height measurements are a standard part of prenatal care, though ultrasound provides more accurate assessment when abnormalities are suspected 1.
- It's worth noting that while the evidence from 1 discusses fetal growth restriction, it does not directly impact the measurement of uterine height at different weeks of gestation, and therefore does not alter the recommendation based on 1.
From the Research
Uterus Height at Different Weeks
- The height of the uterus at different weeks of gestation is not directly addressed in the provided studies 2, 3, 4, 5.
- However, a study on the anatomical development of the fetal uterus found that the distance between the fundus of the uterus and the promontory significantly correlated with the distance between the fundus of the uterus and the pubic symphysis (p<0.001) 4.
- The same study found that the orthogonal lengths of the uterine corpus and cervix correlated with gestational age (p<0.001) 4.
- Another study attempted to establish normal values for uterine involution postpartum, but the results are not directly applicable to uterus height at different weeks of gestation 3.
- The other studies focused on symphysial fundal height measurement in pregnancy 2 and the biological roles of uterine glands in conceptus implantation and uterine receptivity 5, but did not provide information on uterus height at different weeks.