Final answer:
Fetal Heart Tracings analyze various heart rate patterns to assess fetal well-being. Fetal development includes the regular detection of heartbeat around 5-6 weeks gestation, and growth until birth with the potential of IUGR. After birth, the Apgar test assesses the newborn's condition.
Step-by-step explanation:
Fetal Heart Tracings (FHT) are a method to assess the well-being of a fetus by analyzing patterns in heart rate. FHT evaluates several key elements including:
- Normal fetal heart rate pattern
- Sinusoidal rhythm
- Late deceleration
- Variable deceleration
- Early deceleration
During the stages of pregnancy, the fetal heart undergoes significant development. A regular heartbeat can usually be detected around the 5th to 6th week of gestation.
Between week 27 and birth, the fetus experiences significant changes including brain development, and the maturation of respiratory and digestive systems. Fetal blood circulation is distinct from postnatal circulation due to the presence of shunts like the ductus arteriosus and the foramen ovale that bypass the non-functioning lungs.
Fetal hemoglobin differs from adult hemoglobin, having a greater affinity for oxygen which is crucial for efficient oxygen transfer from the mother's blood. Fetal growth in size is typically linear until the latter weeks of pregnancy. Intrauterine Growth Restriction (IUGR), primarily caused by placental insufficiency, can impede this growth. The average weight for a full-term newborn is 3.4 kg (7.5 lb). A birth weight of less than 2.5 kg (5.5 lb) is considered low and is predominantly caused by IUGR or preterm birth.
Fetal viability is a term referring to the age at which a fetus is likely to survive outside of the womb with appropriate medical care, typically around 26 weeks gestation.
Upon birth, the Apgar test assesses the newborn's transition from the womb. This test includes the evaluation of skin colour, heart rate, reflex, muscle tone, and respiration, and leads to a score indicating the newborn's condition.