Post Term Pregnancy: Symptoms, Causes, Complications, Risks, Management & Treatment

Find out all about post-term pregnancy, its causes, symptoms, complications and associated risks.

Introduction

The average pregnancy duration is estimated to be 9 months. Medical professionals are responsible for providing the expectant mothers with a due date considering the last menstrual cycle and other conception details in the first ultrasound examination of a mother-to-be. The Estimated Delivery Date (EDD) is calculated to be 40 weeks/ 280 days from the last menstrual period (LMP) of a woman. It is therefore vital to keep track of your menstrual dates regularly. Irregular periods can contribute to miscalculation of LMP and thereby causing inaccurate calculation of the due date of a pregnant mother.

What is Post-term Pregnancy?

An extension of the gestational period of a woman beyond 42 weeks is called a Post-term Pregnancy. Also known as prolonged pregnancy/ Postdates, this type of condition poses a challenge to health care providers and a source of anxiety for the pregnant woman. This condition is usually diagnosed by doctors through Ultrasound examination, measuring the size of the uterus, monitoring the growth of the fetus, and watching the state of the amniotic fluid inside the womb.

What are the causes of Post-term Pregnancy?

Though the exact cause of why a pregnancy might extend beyond 42 weeks is unknown, there are various factors attributed to a potential post-term gestation.

• The most common of them is the dating of the last menstrual period being inaccurate. This is prevalent in women who suffer irregular periods or miss track of their period dates due to stress or anxiety.
• Previous Post Term Pregnancies, that is, when a mother has had a similar pregnancy before could also be a reason for the condition.
• Genetic factors like when the pregnant mother, herself, was a baby of post-term pregnancy; her twin sibling being a mother who went through such a pregnancy can be attributed to longer pregnancies.
• Primiparity where a woman is giving birth for the first time has been an influence in post-term pregnancies.
• Studies have revealed that abnormal BMI is an important yet modifiable factor in extended gestation. An obese woman has a higher chance of going through a post-term pregnancy, while a woman with a low BMI has the chance of having a preterm pregnancy. Conscious dietary changes and a healthy lifestyle can bring positive changes during pregnancy.
• Post-term pregnancies are sometimes indicative of a male fetus.

Post-Term Pregnancy Signs and Symptoms

The symptoms of a post-term pregnancy are almost none. It is usually known after the diagnosis. But there are some impacts that a post-term baby has while inside the womb.

• Dry skin could be caused due to the baby being in the womb for a prolonged period.
• Long nails and excess hair growth can be witnessed
• The baby might look abnormally thin with long hands and legs. This is attributed to the improper functioning of the placenta (Uteroplacental Insufficiency).
• Meconium stains can make the baby’s hands and nails look yellow or green.

What are the risks involved in a Post Term Pregnancy?

Post Term Pregnancy risks in the newborn can be critical. Some of them include

1. Neonatal Mortality

The odds of stillbirths after the said period of gestation are high. Though relatively small, the cases of newborn morbidity should be considered in labor.

2. Foetal Dysmaturity

Post maturity is a condition where the growth of the baby is restricted after a certain time because of inadequate nourishment inside the uterus. These babies tend to have distinctive appearances.

3. Body Size variation:

Some babies are born with larger body sizes (a condition called Macrosomia) where the weight of the infant could be over 5000 grams. This may cause threats to the mother in labor as well as birth injury in the infant.

4. Hypoglycemia

This condition is characterized by low levels of sugar in the blood. Neonatal hypoglycemia is caused due to the exhaustion of sugar supply in the blood of the baby.

5. Inhalation of Meconium

Meconium is the first stool that the baby passes from its body. In Post-term labor, there is a possibility of this substance getting released into the amniotic fluids and the baby could breathe it, causing fatal effects.

What are the Post-Term Pregnancy Complications in the Mother?

The condition is as strenuous for the mother as it is for the fetus. Longer labor is a typical struggle associated with this type of pregnancy. Since the fetal size could be bigger, there are risks of Cephalopelvic disproportion (where the baby finds it difficult to come through the vaginal path either because the baby’s head is larger or the mother’s pelvis is smaller) and shoulder dystocia (where the shoulder of the fetus gets stuck in the birth canal). In similar cases, the doctors may use a vacuum or forceps to aid the birthing process. Sometimes, in more serious cases, the health care providers may opt for a cesarean delivery to save the lives of both the mother and the baby. Other Complications include Infection or wound in the organs surrounding the uterus and vagina and loss of blood.

Post Term Pregnancy Management and Treatment:

Ultrasound examination from the early weeks of pregnancy is the best form of managing a post-term pregnancy. It can reduce considerable risks involved in labor and neonatal care. Once the mother is diagnosed with a post-term, a few tests are recommended to ensure that the mom and the baby are safe.

A Biophysical profile (a test done in pregnancy) is done to monitor the fetal movements, frequency of fetal heartbeat also known as Nonstress testing, and the volume of Amniotic fluid in the uterus. Sometimes the level of amniotic fluid may go down resulting in a condition called Oligohydramnios. Any abnormal variation in the mentioned tests could cause fetal stress.

In such cases, the care providers will make attempts to induce labor. With mothers having unfavorable cervix during labor, post-term pregnancy treatment involves employing methods like membrane sweeping, injecting oxytocin via drips, and giving prostaglandin to ripen the cervix. These can make the dilation happen faster and aid in reducing post-term delivery complications.

Summary

• Post-term Pregnancy is when the gestational age of a mother extends beyond 42 weeks.
• Several factors like a miscalculation of LMP, genetic factors, obesity, and hormonal reasons influence the possibilities of a post-term.
• The risks of post-term pregnancies can be seen in both the mother and the fetus.
• Frequent Ultrasound examinations and continuous fetal monitoring are required to manage the complications.
• Inducing labor after the due date can help in minimizing the post term pregnancy risks.

References

1. Galal M, Symonds I, Murray H, Petraglia F, Smith R. (2012). Postterm pregnancy. www.ncbi.nlm.nih.gov
2. Prajapati, S. Chavda, D. (2017). Retrospective study of post term pregnancy and its outcome.www.ijrcog.org