Does Measuring SFH Detect Fetal Growth Restriction?

There is insufficient evidence to determine whether measurement of symphysis fundal height (SFH) can effectively detect intrauterine growth restriction (IUGR), concludes a new systematic review.¹

Fetuses with IUGR have an increased risk of cesarean delivery, hypoxia, meconium aspiration, hypoglycemia, polycythemia, hyperviscosity, and motor and neurological disabilities. Certain maternal characteristics, such as being underweight, having poor nutrition, birth defects or chromosomal abnormalities, illicit drug use, smoking cigarettes, alcohol use, pregnancy induced hypertension, placental abnormalities, umbilical cord abnormalities, multiple pregnancy, gestational diabetes, and oligohydramnios, also may increase risk of IUGR during pregnancy.²

SFH measurement-the length between the mother’s symphysis pubis to the top of the womb-and abdominal palpation are the simplest ways to assess fetal growth. In many clinical practices, however, SFH measurement has replaced abdominal palpation because the latter has been reported to be a poor predictor of fetal growth.³ Yet, there is little evidence showing that SFH has better predictive value.

Researchers in Malaysia sought to compare SFH measurement with serial ultrasound measurement of fetal parameters or clinical palpation to detect abnormal fetal growth, both IUGR and large for gestational age. Only 1 trial fit the predetermined selection criteria; it involved 1639 women and compared repeated SFH measurement with clinical abdominal palpation.

Incidence of small for gestational age and perinatal death were the primary outcomes of the included study, and researchers found no differences in these outcomes between the SFH measurement group and the abdominal palpation group. The reported secondary outcomes, which were neonatal hypoglycemia, admission to a neonatal ICU for IUGR, induction of labor, and cesarean delivery, were also similar between study groups.

Because of insufficient evidence, researchers were unable to determine whether SFH measurement is an effective tool for detecting IUGR, which is consistent with the conclusion of another similar study.³ Ultrasonography can detect abnormal fetal growth, but compared with manual measurement of fundal height, which provides results that are nearly equivalent to those found with ultrasound, it is a high-cost tool that may not be available in all areas. ⁴ When there is a discrepancy between gestational age and size, ultrasonography is best.⁴ One of the most important factors in detecting abnormal fetal growth is ensuring that the pregnancy has been dated correctly.

Pertinent Points:
- There is insufficient evidence to determine whether measurement of SFH can effectively detect IUGR.
- An accurate gestational age will provide more meaning to any measure-manual or ultrasound-of gestational size.