Childbirth Complications (cont.)
Sometimes the baby is not facing the mother's back, but instead is turned toward her abdomen (occiput or cephalic posterior). This increases the chance of painful "back labor," a lengthy childbirth or tearing of the birth canal. In malpresentation of the head, the baby's head is positioned wrong, with the forehead, top of the head or face entering the birth canal, instead of the back of its head.
Some fetuses present with their buttocks or feet pointed down toward the birth canal (a frank, complete or incomplete/footling breech presentation). Breech presentations are normally seen far before the due date, but most babies will turn to the normal vertex (head-down) presentation as they get closer to the due date. In a frank breech, the baby's buttocks lead the way into the pelvis; the hips are flexed, the knee extended. In a complete breech, both knees and hips are flexed and the buttocks or feet may enter the birth canal first. In a footling or incomplete breech, one or both feet lead the way. A few babies lie horizontally (called transverse lie) in the uterus, which usually means the shoulder will lead the way into the birth canal rather than the head.
Abnormal presentations increase a woman's risk for injuries to the uterus or birth canal, and for abnormal labor. Breech babies are at risk of injury and a prolapsed umbilical cord. Transverse lie is the most serious abnormal presentation, and it can lead to injury of the uterus (ruptured uterus) as well as fetal injury.
Your doctor will determine the presentation and position of the fetus with a physical examination. Sometimes a sonogram helps in determining the fetus' position. When a baby is in the breech position before the last six weeks to eight weeks of pregnancy, the odds are still good that the baby will flip. However, the bigger the baby gets and the closer you get to the due date, the less room there is to maneuver. Doctors estimate that about 90% of fetuses who are in a breech presentation before 28 weeks will have turned by 37 weeks, and over 90% of babies who are breech after 37 weeks will most likely stay that way.
Umbilical Cord Prolapse
The umbilical cord is your baby's lifeline. Oxygen and other nutrients are passed from your system to your baby, through the placenta and the umbilical cord. Sometimes before or during labor, the umbilical cord can slip through the cervix, preceding the baby into the birth canal. It may even protrude from the vagina. This is dangerous because the umbilical cord can get blocked and stop blood flow through the cord. You will probably feel the cord in the birth canal and may see it if it protrudes from your vagina. This is an emergency situation. Call an ambulance to get you to the hospital.
Umbilical Cord Compression
Because the fetus moves a lot inside the uterus, the umbilical cord can get wrapped and unwrapped around the baby many times throughout the pregnancy. While there are "cord accidents" in which the cord gets twisted around and harms the baby, this is extremely rare and usually can't be prevented.