Transverse lie is a situation where a baby is lying sideways in the uterus prior to delivery. It is usually not possible to deliver vaginally when a baby is in this position, because while the cervix and vagina are elastic and able to expand, they are not elastic enough to accommodate a baby coming out sideways. When it becomes apparent that a baby is in this position, there are some options that can be pursued to see if the baby can be moved before the mother goes into labor. If the baby stays put, a Cesarean section is usually recommended for delivery.
Early on in pregnancy, the fetus changes positions a lot, as many expecting mothers have noticed. At various stages, the fetus may be lying sideways. As the fetus develops and grows larger, however, a vertical position tends to be assumed because the shape of the uterus pushes the fetus to be either upside down or right side up. The upside down position is ideal, allowing the baby to be delivered head first. If the baby is right side up, with the feet facing down, he or she is said to be in breech position.
An ultrasound examination in the late stages of pregnancy will determine the position the baby is lying in, and whether action needs to be taken to move the baby or change the birth plan. Sometimes it is possible to encourage a shift out of transverse lie into a safer position for delivery. Expecting mothers can use various exercises and the baby can be manipulated from the outside by a trained care provider. If the baby moves into the right position and stays there, delivery can proceed as planned. If it does not, it may be time to discuss a Cesarean section. Laboring with the baby in this position is usually not recommended.
Some people are at increased risk of developing a transverse lie. Women who have had multiple pregnancies, women expecting twins or higher order multiples, women with unusual uterine shapes, or women with growths that block the fetus can all be more likely to experience a transverse lie. It is not possible to prevent a shift into a position dangerous for delivery, but if it is identified early enough, it may be possible to move the baby.
The risk that a baby may end up in a breech or transverse lie is one very important reason to receive routine prenatal care. If these risks are not identified before labor begins, it can endanger the mother and the baby.