What causes abnormal fetal position?

Under normal circumstances, abnormal fetal position may be caused by multiple factors such as multiple pregnancies, fetal size, amniotic fluid abnormalities, uterine malformations, and placenta previa. It is recommended to seek medical attention promptly, identify the underlying cause, and receive symptomatic treatment under the guidance of a qualified healthcare provider. Specific analysis is as follows:

1. Multiple Pregnancy

In cases of multiple pregnancy, the presence of several fetuses within the uterus occupies more space, reducing the room available for each individual fetus to adjust its position. Particularly in late pregnancy, as fetal volume increases, spatial constraints become more pronounced, making it difficult for the fetus to naturally rotate into the cephalic (head-down) delivery position, thus leading to abnormal fetal presentation. Usually, no specific treatment is required. Regular prenatal check-ups are important to closely monitor fetal position and maternal health.

2. Fetal Size

When the fetus is too large, the intrauterine space becomes relatively limited, restricting the fetus’s ability to turn freely. Conversely, when the fetus is too small, excessive movement range may prevent it from settling into the optimal cephalic position. Both situations can lead to abnormal fetal position. Generally, no special treatment is needed. For cases of fetal macrosomia, it is important to control maternal blood glucose and weight. For smaller fetuses, enhanced nutritional support is recommended, and delivery plans may need to be arranged earlier if necessary to ensure maternal and fetal safety.

3. Amniotic Fluid Abnormalities

Abnormal amniotic fluid levels may result from factors such as intra-amniotic infection or premature rupture of membranes. Excessive amniotic fluid (polyhydramnios) increases intrauterine pressure and restricts normal fetal movement, while insufficient amniotic fluid (oligohydramnios) lacks adequate cushioning, limiting fetal mobility. Both conditions may contribute to abnormal fetal position and may be accompanied by symptoms such as breathing difficulties and abdominal distension. For polyhydramnios, the underlying cause should be identified and treated. For oligohydramnios, close monitoring of fetal status is essential, and delivery may need to be planned earlier to prevent fetal distress.

4. Uterine Malformation

Uterine malformations may arise due to factors such as chromosomal nondisjunction in germ cells or exposure to sex hormone medications. These structural abnormalities alter the internal geometry of the uterus, restricting fetal movement and impairing the fetus's ability to naturally assume the cephalic position, resulting in abnormal fetal presentation. This condition may also be associated with recurrent miscarriage or preterm birth. Surgical intervention at a reputable hospital may be considered, such as hysteroscopic resection of a uterine septum.

5. Placenta Previa

Placenta previa may be caused by endometrial injury or pathology, or placental abnormalities. In this condition, the placenta covers the cervical opening, obstructing the fetal descent pathway and preventing the fetus from rotating into the cephalic position, thereby causing abnormal fetal presentation. It may be accompanied by painless vaginal bleeding. Treatment may include medications such as cephalexin capsules, progesterone capsules, or Baotailing capsules, as prescribed by a physician.

In daily life, adequate rest should be maintained to avoid excessive fatigue. A balanced diet is important, with increased intake of protein-rich foods. Appropriate physical activity may also help correct abnormal fetal position.