Common Causes of Fetal Growth Stoppage at Six Weeks of Pregnancy

There are several common reasons why a fetus may suddenly stop growing in the womb. The most prominent include high maternal blood pressure, multiple pregnancies, infections, and smoking during pregnancy. Regular monitoring of the baby’s growth and development is essential to avoid complications. Growth delay at six weeks of pregnancy can be linked to certain health conditions affecting the mother. Here are the main causes according to the website thehansindia.

What Causes Fetal Growth to Stop at Six Weeks?

1. High Blood Pressure During Pregnancy

High blood pressure reduces blood flow to the placenta.

This is one of the most significant causes of slowed or stopped fetal growth. Pregnant women must monitor their blood pressure regularly to protect themselves and the baby. Reduced blood flow to the placenta limits the oxygen and nutrients reaching the fetus.

2. Multiple Pregnancies

Growth delay or stoppage occurs in 25–30% of twin pregnancies.

This happens because the placenta may not meet the nutritional needs of multiple fetuses, and the risk of high blood pressure is also higher.

3. Infections

Any infection during pregnancy—such as syphilis or rubella—can pass from the mother to the baby and slow fetal growth, especially in the first trimester.

4. Low Amniotic Fluid

Low levels of the fluid surrounding the baby may result from:

Mother’s health condition
Certain medications
Small tears in the amniotic sac

These factors reduce fluid levels and affect normal fetal development.

5. Placental Insufficiency

Sometimes, the placenta does not function properly, leading to:

Inadequate oxygen and nutritional supply to the baby
Reduced or stopped growth

Women may notice less fetal movement and a smaller uterus size.

6. Umbilical Cord Abnormalities

The umbilical cord connects the fetus to the placenta. It should contain one vein and two arteries. Any abnormality—such as having only one artery—can affect nutrient and blood supply, slowing growth.

7. Other Causes

Additional maternal or fetal factors include:

Small maternal body size
Poor maternal nutrition
Abnormal shape or size of the uterus
Chronic maternal illnesses (anemia, diabetes, heart disease, hypertension)
Chromosomal abnormalities
Genetic or structural fetal deformities
Smoking
Exposure to high radiation or chemicals

Risks of Fetal Growth Stoppage

Growth arrest during the sixth week may lead to serious complications, including:

Miscarriage
Premature birth
Infections
Breathing difficulties

When to See a Doctor

If any sign of slowed or stopped growth is detected, an ultrasound is performed to measure fetal development. Immediate medical evaluation is necessary to reduce potential risks and manage the condition.