How is gestational age determined from fetal heart rate patterns?

Determining gestational age through fetal heart rate patterns involves evaluating the normal range and variability of heart rate changes. As pregnancy progresses, the fetal heart rate undergoes predictable changes. For instance, a specific range of heart rates is associated with different gestational ages, and the patterns of variability and accelerations can indicate the maturity of the fetal autonomic nervous system.

Different gestational ages will have characteristic fetal heart rate patterns; for instance, the baseline heart rate typically stabilizes and variability increases as the pregnancy advances. This knowledge allows clinicians to assess whether the fetal heart rate patterns are appropriate for the gestational age, helping identify issues such as fetal distress or growth restriction.

The other options do not directly relate to the determination of gestational age via heart rate patterns. Monitoring maternal weight or blood pressure does not provide specific insight into the gestational age of the fetus. While ultrasound measurements are indeed a reliable method for determining gestational age, they do not utilize fetal heart rate patterns, thereby making those options less relevant in this context.