A transverse fetal lie occurs when a baby is positioned horizontally across the mother’s abdomen instead of vertically. This orientation means the fetal head or buttocks are not aimed toward the birth canal, preventing the presenting part from engaging in the pelvis. Because the baby cannot lead the way through the pelvis, this position makes a safe vaginal birth impossible. The goal is to encourage the baby to rotate into the safer, head-down position before labor begins.
Understanding Transverse Lie
A baby’s position, or fetal lie, is assessed during the third trimester of pregnancy, with a transverse lie often diagnosed after 32 to 34 weeks of gestation. While many babies are sideways early in pregnancy, most move into a head-down orientation by the final weeks. The persistence of a transverse lie at term is rare, occurring in about one in every 400 births.
Several factors contribute to a baby remaining in a transverse position, often relating to excess space or obstructions within the uterus. These factors include:
- Polyhydramnios (too much amniotic fluid), which provides ample room for the baby to settle sideways.
- Multiple previous pregnancies, as stretched uterine and abdominal muscles create a relaxed environment where the baby can easily shift.
- Placenta previa, where the placenta covers the cervix.
- Structural issues like uterine malformations or fibroids that physically impede the baby’s ability to turn vertically.
Diagnosis is confirmed through a physical abdominal examination and an ultrasound scan, which provides the definitive image of the baby’s horizontal orientation.
At-Home Techniques for Fetal Positioning
Before considering medical intervention, at-home methods focus on creating optimal space and balance within the pelvis to encourage a natural turn. These techniques utilize gravity and relax the uterine ligaments that may be holding the baby horizontally. Any at-home technique should only be attempted after receiving clearance from a healthcare provider.
Forward-Leaning Inversion
One frequently used technique is the forward-leaning inversion, which involves briefly positioning the body upside down, such as kneeling on a couch and lowering the forearms to the floor. This maneuver temporarily releases tension in the uterine ligaments, allowing the baby to rotate freely. Guidelines suggest performing this inversion for 30 to 45 seconds multiple times daily. Following this technique with positional exercises, such as the side-lying release, can further encourage pelvic symmetry and soft tissue relaxation.
Webster Technique
The Webster Technique is performed by a chiropractor specializing in prenatal care. This method focuses on adjusting the sacrum and addressing muscular tension in the mother’s pelvis, rather than manually turning the baby. The goal is to correct asymmetry that causes uneven tension on the ligaments supporting the uterus. Reducing this tension optimizes the space within the pelvis, giving the baby the opportunity to move into a head-down position. Simple practices like maintaining an upright posture and avoiding deep, slouchy seating also help create more room for the baby.
Medical Procedure External Cephalic Version
If at-home methods are unsuccessful, External Cephalic Version (ECV) is a medical procedure offered around 36 to 37 weeks of pregnancy. A physician performs this procedure in a hospital setting near an operating room in case of complications. ECV involves the doctor placing their hands on the mother’s abdomen and applying firm pressure to manually guide the baby into the head-down position.
The procedure is performed under ultrasound guidance to monitor the baby’s movement. Medication like terbutaline may be administered to the mother to relax the uterine muscle, making the manual rotation easier and increasing success. ECV has an average success rate of about 58%. Although the procedure can cause cramping and discomfort, it is usually completed within a few minutes, and the baby’s heart rate is monitored closely afterward.
Timeline Risks and Delivery Options
The goal of encouraging a baby to turn before labor is to avoid risks associated with an unresolved transverse lie. The most serious concern is umbilical cord prolapse if the amniotic sac ruptures before the baby engages in the pelvis. When the membranes break, the lack of an engaged head or buttocks allows the umbilical cord to slip down ahead of the baby. This cord compression restricts the baby’s oxygen supply and constitutes an obstetric emergency.
Patients with a known transverse lie are advised to go directly to the hospital if their water breaks or if they begin experiencing contractions. If all attempts to turn the baby are unsuccessful, a planned Cesarean section is the safest delivery option. A vaginal delivery is dangerous when the baby is lying sideways because the shoulder or arm is the presenting part, which cannot pass through the birth canal. A scheduled C-section ensures a safe delivery for both mother and baby.