Full-Term Fetal and Placental Knowledge

Full-Term Fetal and Placental Knowledge

This article will provide information about the characteristics of the fetus and placenta during full-term pregnancy, including:

Amniotic Fluid:

• Function: Protects the fetus from impacts and trauma; Lubricates the birth canal after the amniotic sac ruptures, making delivery easier; Helps the fetal presentation to align correctly.

• Origin: Amniotic fluid is produced by the mother’s uterine lining and is partially reabsorbed by the fetus through swallowing and through the fetal skin. In addition, amniotic fluid is reabsorbed through the fetal airways.

• Role: Protects the fetus from trauma, helps the fetus balance water and electrolytes, nourishes the umbilical cord, prevents compression of the fetus on the umbilical cord and placenta.

• Renewal: Amniotic fluid is constantly renewed in a cycle of 3 hours/time.

• Amount: The average amount of amniotic fluid at 12 weeks of gestation is 50 ml. The highest amount of amniotic fluid is at 18-24 weeks of gestation.

Fetus:

• Full-term gestation: 38 – 42 weeks

• Average weight: 3000g

• Circulatory characteristics: There is a foramen ovale and ductus arteriosus, creating a difference compared to the circulatory system of an adult.

• Head characteristics: The head can be molded due to different diameters, allowing the fetal head to reduce its diameters when passing through the birth canal.

• Head diameters:

• Suboccipitobregmatic: 9.5 cm

• Biparietal: 8.5 cm

• Submentobregmatic: Smallest when the fetal head is maximally flexed.

Placenta:

• Placenta: Average diameter 15cm.

• Umbilical cord: Average diameter 1.5cm, average length 40-60cm. Consists of 2 arteries and 1 vein.

• Amniotic membrane: Chorion is derived from the uterine endometrium.

• pH of amniotic fluid: 7.1 – 7.3.

Additional information:

• Orange-colored cells: These are cells without a nucleus, which stain orange when stained with Nile blue. They begin to appear very early, from the fourth week of gestation, and are a factor in determining fetal maturity.

• Anterior fontanel: Has a quadrangular shape.

• Posterior fontanel: Has a triangular shape.

• Fetal presentation that can be delivered vaginally: Vertex, face chin anterior, breech.

• Oxygen and carbon dioxide exchange between maternal and fetal blood: Maternal blood pressure in the placental lake is lower than fetal blood and flows slowly. Carbon dioxide levels are lower, but oxygen levels are higher than fetal blood. Fetal hemoglobin has a high oxygen binding capacity.

• Protein passing through the placenta: In the form of amino acids.

• Vitamin K deficiency: Leads to bleeding disorders due to reduced prothrombin levels in newborns.

• HCG: Can be detected 8-9 days after fertilization (when implantation occurs).

Note:

• The information in this article is for informational purposes only.

• For more detailed information and to find out what’s right for your specific situation, please consult with a medical specialist.