OVERVIEW

What is fetal position?

Fetal position refers to the posture of the fetus in the uterus. Since the exit of the uterus is at the bottom, the presenting part during delivery serves as the indicator of fetal position, such as:

• Vertex position means the baby's head is facing downward, near the uterine exit.
• Breech position means the baby's buttocks are facing downward, with the head upward.

Additionally, the baby's orientation matters. If the baby is in a vertical or upside-down position when the mother stands, this is a normal longitudinal fetal position. If the baby lies horizontally when the mother stands, this is a transverse fetal position.

Can fetal position change?

Fetal position can change.

• At earlier gestational ages, the fetus can move freely in the uterus, causing the position to change constantly.
• As gestational age increases and the fetus grows, space in the uterus becomes limited. After 28 weeks, the fetal position gradually stabilizes.
• After 38 weeks, the chance of the fetal position changing naturally is low. About 25% of breech-positioned fetuses may turn to a vertex position after 36 weeks, but if there are fetal or uterine abnormalities, the likelihood of natural change is minimal.

What is an abnormal fetal position?

The normal delivery position is occiput anterior. Any other position is considered abnormal, including persistent occiput posterior, persistent occiput transverse, face presentation, breech position (including footling or frank breech), and transverse lie (shoulder presentation).

The most common abnormal position is breech, where the baby's buttocks are down and head is up, with the buttocks emerging first during delivery (also called breech presentation). This occurs in 3%–4% of full-term deliveries.

Before 30 weeks, abnormal fetal positions do not require intervention, as the position is not yet fixed. If the fetus remains in a breech or transverse position at 32–34 weeks, external cephalic version may be considered.

SYMPTOMS

What are the symptoms of abnormal fetal position?

• Abnormal fetal position is a common cause of difficult labor. Most cases show no symptoms before delivery.
• In breech presentation, mothers may frequently feel the shape of the baby's head in the upper abdomen. Before delivery, abnormal position may lead to prolonged labor, fetal distress, maternal and neonatal birth injuries, and in critical cases may cause neonatal death or maternal hemorrhagic shock.

CAUSES

What are the common causes of malposition?

• Premature birth;
• Multiple pregnancies: twins, multiple births;
• Cephalopelvic disproportion: narrow maternal pelvis, oversized fetal head;
• Uterine abnormalities: unicornuate uterus, bicornuate uterus, etc.;
• Placental abnormalities: placenta previa, cornual placenta, short umbilical cord;
• Amniotic fluid abnormalities: premature rupture of membranes, oligohydramnios, polyhydramnios;
• Fetal abnormalities: such as anencephaly;
• Maternal obesity, advanced maternal age.

If the first pregnancy had malposition, does the risk of malposition increase in the second pregnancy?

There are many causes of malposition. Mothers who had malposition in their first pregnancy have a slightly higher chance of experiencing it again in the second pregnancy compared to those who did not (for breech presentation, the likelihood of recurrence is 2%).

Therefore, mothers with a history of malposition should attend regular prenatal check-ups during their second pregnancy to allow for early intervention if needed.

DIAGNOSIS

What tests are needed to diagnose abnormal fetal position?

• Obstetric examination - Palpation to assess fetal position;
• Color ultrasound: Determines fetal orientation;
• Vaginal digital examination: Palpation to evaluate fetal position.
  These examinations are usually sufficient to confirm fetal position.

TREATMENT

Which department should I visit for abnormal fetal position?

Obstetrics or gynecology.

How is abnormal fetal position treated?

• Before 30 weeks, no intervention is needed as the fetal position is not fixed. Continue regular prenatal checkups.
• At 32–34 weeks, if the fetus is in a breech or transverse position, external cephalic version (ECV) may be considered: The doctor manually adjusts the fetus to a head-down position by manipulating the mother's abdomen. Due to risks like placental or umbilical cord injury, this procedure requires careful evaluation.
• If the abnormal position persists before delivery: The delivery method (vaginal birth, forceps-assisted delivery, or cesarean section) is chosen based on fetal position, maternal condition, and fetal health.

When is a cesarean section necessary?

Surgical delivery is required in the following cases:

• Failed vaginal delivery attempt (e.g., for head-first presentation);
• Fetal distress;
• Maternal health conditions preventing vaginal delivery;
• Large fetal size;
• Narrow pelvis;
• Transverse lie (shoulder presentation);
• High-risk breech position.
  Since conditions may change, mothers with abnormal fetal positions should attend regular checkups and arrive early at the hospital before labor. Following medical advice ensures the safest delivery method.

Is follow-up needed after discharge for abnormal fetal position?

Yes, mothers with abnormal fetal positions are prone to birth injuries and must return to the gynecology department for a postpartum checkup at 42 days. Seek immediate medical help if experiencing severe pain, heavy bleeding, difficulty urinating, foul-smelling lochia, incontinence, fever, perineal swelling, or debilitating anxiety/depression during recovery.

Can acupuncture or yoga correct abnormal fetal position?

Traditional Chinese medicine suggests acupuncture may help adjust fetal position, but its efficacy remains uncertain due to limited studies. If attempted, it should be performed at a licensed hospital with fetal monitoring. Do not skip prenatal checkups.

All correction methods carry failure risks. If unsuccessful, timely cesarean delivery and regular checkups remain the safest options.

The knee-chest position (on hands and knees, hips elevated, 10 minutes 2–3 times daily) is traditionally believed to help after 30 weeks, but recent studies question its effectiveness, attributing spontaneous turns to natural fetal movement. While harmless, mothers may try it under medical guidance but should avoid unverified remedies like self-administered massage or herbal treatments.

DIET & LIFESTYLE

What should pregnant mothers with abnormal fetal positions pay attention to in their daily diet and lifestyle?

Do not deliberately stay in bed, as prolonged immobility increases the risk of blood clots. Maintaining normal activity is actually beneficial for the body. However, avoid intentionally climbing stairs or jumping, as these intense activities may cause injury to the pregnant mother. Simply maintaining regular daily activities is sufficient.

As a pregnant mother, it is important to control weight gain. Excessive weight gain during pregnancy leading to obesity can result in a difficult labor. Additionally, an overly large fetus may cause cephalopelvic disproportion, making delivery challenging. Therefore, focus on a diet rich in high-quality protein but avoid excessive consumption of fatty foods. For example, when eating stewed pork ribs or trotters, consume the meat but not the broth, as the broth contains more fat and little protein.

PREVENTION

Can Malposition of the Fetus Be Prevented?

Since there are many causes of abnormal fetal positions, it is not possible to prevent all cases in advance. Controlling prenatal weight and maintaining muscle strength can help avoid malpositions caused by an oversized fetus or insufficient labor force, but it cannot completely prevent all occurrences of abnormal fetal positions.

Regular prenatal checkups can detect malpositions early, and proactive early preparation can make childbirth safer and smoother.