Health Pregnancy

Delayed intrauterine growth: what is it and what are its causes?

The most important thing to avoid delayed intrauterine growth is to have healthy habits during pregnancy and even before conception. Once that state occurs, it becomes irreversible.

Delayed intrauterine growth: what is it and what are its causes?

Delayed, or restricted intrauterine growth, refers to an abnormal slowdown in the growth of the fetus within the uterus. The consequence is that the baby does not reach the appropriate size and therefore has a higher risk of complications at birth or even death.

Delayed intrauterine growth can be intrinsic or extrinsic. The first depends on the characteristics of the fetus, such as malformations. The second is influenced by factors outside the fetus and can be symmetric or asymmetric. The symmetric is originated by nutritional deficit of the mother; the asymmetric, due to a failure in the placenta.

Sometimes the growth is less during the whole gestation and then we speak of low profile CIR. If this only occurs in the third trimester, we speak of CIR with late flattening. Not all babies who are born smaller and with low weight correspond to cases of delayed intrauterine growth.

Causes of retarded intrauterine growth

Delayed intrauterine growth: what is it and what are its causes?

Delayed intrauterine growth implies an abnormal slowdown in the growth of the fetus within the uterus.

There are many factors that can lead to delayed intrauterine growth. Typically, these are classified into three groups: maternal, utero-placental and fetal.

Cardiovascular diseases in the mother, such as hypertension, reduce the amount of blood and oxygen that reaches the placenta. Something similar occurs with metabolic diseases that restrict the arrival of nutritional substances to the fetus.

On the other hand, delayed intrauterine growth is also caused by a failure in the placenta. For example, fibroids, uterine scars, premature aging of the placenta, placental infarction or others. This prevents the normal growth of the fetus.

Some chromosomal abnormalities (Down syndrome and others) or congenital malformations cause delayed intrauterine growth. The same occurs when there are intrauterine infections that affect the fetus, such as rubella, toxoplasmosis or cytomegalovirus.

Risk factor’s

Risk factors for delayed intrauterine growth can be divided into three groups: environmental, inappropriate habits, and socioeconomic factors. Let’s see.

Environmental factors. They include living at high altitudes, exposure to environmental pollution, hot weather conditions and low rainfall (climate change), and some drugs.
Inappropriate habits. The use of tobacco, alcohol, heroin, or cocaine has been associated with retarded intrauterine growth.
Socioeconomic factors. Malnutrition in the mother, strenuous jobs, poverty, and rotating shift work are factors that can alter the normal growth of the fetus.

Diagnosis of delayed intrauterine growth

A rudimentary and old way of establishing delayed intrauterine growth is with a measurement of the length of the uterus. It is taken from the pubis to the upper end of the abdomen. It is estimated that it is possible to obtain up to 70% correct diagnoses with this method.

Currently, the most effective method to diagnose this abnormality is ultrasound. This allows to detect, among other aspects, the following:

State of the placenta.
Amniotic fluid volume.
Fetus weight.
Diameter of the head of the fetus.
Measurement of abdominal circumference.
Doppler flowmetry allows you to measure the blood flow of the arteries that carry blood to the placenta. This makes it possible to detect any abnormality early, which is why it has an advantage over traditional ultrasound. Both methods also lead to establish if there are congenital anomalies.

How is retarded intrauterine growth treated?

Delayed intrauterine growth increases the risk of fetal death before birth. Therefore, from the diagnosis, a careful follow-up of the pregnancy must be carried out, using periodic ultrasounds.

Such follow-up also usually includes a resting cardiotocogram. This allows you to listen to the baby’s heart rate for a period of 20 to 30 minutes. It also helps to establish the general state of well-being of the baby and the presence of contractions.

If there are failures in the placenta or the growth of the fetus stops, the usual thing is that the delivery is advanced. In most cases, a cesarean section is performed. If the pregnancy is advanced and there are no failures in the placenta, a vaginal delivery may be attempted.

Tips to prevent intrauterine growth retardation

Delayed intrauterine growth: what is it and what are its causes?

Control of risk factors is the best prevention of this pathology.

Delayed intrauterine growth can be prevented, mainly by controlling risk factors. Once this anomaly is installed, there is no way to reverse it, hence the importance of applying prevention measures.

The most important thing is that the mother avoid the consumption of substances with toxic potential, such as tobacco, alcohol and drugs. It is not advisable to take any drug without medical advice. It is also important to avoid stress.

The mother must have a balanced diet, rich in blue fish, fruits and vegetables. It is also advisable for her to exercise regularly and take care of her emotional health. If she has any disease, she must follow all medical recommendations to keep it under control.

It is very important to see a doctor from the beginning of pregnancy. In this way, it can be detected if there are risk factors. On the other hand, regular consultations should be carried out without delay to detect any possible anomalies in time.

After delivery, medical follow-up is necessary

If there are no complications associated with delayed intrauterine growth, once the baby is born, its development is continuously monitored. In most cases this allows it to grow normally and reach normal weight and height.

It is common that if growth has been significantly delayed, the baby experiences more stress during delivery and a cesarean section is necessary. Typically, delayed intrauterine growth does not recur in subsequent pregnancies.