Difficult labor, referred to medically as dystocia, is generally by three types of abnormalities:
- Uterine “ineria” contractions of the uterus are too weak, too infrequent, or too brief.
- Faulty presentation or abnorrnal development of the fetus, so that it cannot be expelled with the face to the rear of the mother.
- Abnormalities of the birth canal (including the pelvis, cervix, and vagina), forming obstacles to the descent of the fetus. The most common cause of difficult labor is the combination of an abnormally contracted pelvis associated with uterine dysfunction.
Surprisingly, the patient’s physical condition usually has no influence on the contractions (i.e., poor or
weak contractions do not necessarily indicate a poor physical condition.) Also, “dry labor,” due to premature rupture of the amniotic sac, has no influence on it, nor does dry labor adversely affect delivery in any way. The usual treatment for inadequate uterine contractions is drug therapy, and there are a number of effective medications available for use in stimulating labor.
When the fetus arrives in the pelvis with the buttocks first and the head last, this is called a “breech
presentation.” It occurs in 3 to percent of deliveries. Usually, wit} this type of presentation, spontane ous delivery is permitted until umbilicus has been born. The “footling breech,” in which the feet actually do appear first, is an easier operation. In the breech presentation, the head follows the body and enters the birth canal chin first. Therefore, the skull cannot mold as readily to the birth canal and has slightly more diffculty getting through. Special care is taken to prevent the umbilical cord from becoming tangled or constricted as it passes along with the baby’s head through the pelvic canal.
Occasionally, when the obstetrician suspects that the fetus is about to settle into the breech position in the pelvis just before labor is expected, he may attempt to manipulate the child’s position (version) from the outside. However, if the head does not engage immediately in the pelvis, the body turns about again. Version also may be attempted after labor has started, but since breech extractions are easily performed now and involve no unusual risk, the birth may proceed as a breech. Version generally is attempted when the child presents in a transverse position, lying across the direction of the birth canal. In this case the doctor reaches into the vagina and up into the uterus to grasp the baby’s feet, pulling them through first, for a “footling” breech extraction.
Abnormalities of Passage
When the fetus appears unable to get through some segment of the canal, or the mother cannot push, the obstetrician will often use a forceps—a tong-like instrument whose ends are curved to fit the infant’s head. Low, or outlet, forceps are more widely used in this country to ease the child’s journey past the tough perineal tissue and spare the mother that formidable last strain. Forceps often leave some clamp marks on the baby’s head which disappear a few days after birth and are no cause for alarm.
Some 5 to 7 percent of the births in the United States require cesarean section. Performed for a variety of reasons, the most common cause is a constricted pelvis through which the fetus would pass with diffculty. Other reasons are pelvic tumor, abnormal fetal presentation, premature separation of the placenta or placenta previa (referring to a very low insertion of the placenta in the uterus). Both placental abnormalities might lead to a fatal hemorrhage if delivery were permitted through the normal passage. To perform the cesarean section, an incision is made through the mother’s abdominal and uterine walls and the baby is lifted out. The incision may be made longitudinally, to the pubic bone, or from side to side, low in the abdomen along the pubic ridge.
Cesarean section now is a safe operation. The risk to the mother is 2 or 3 times greater than that of normal delivery, but its safety is far greater, however, than that of some other, obstetrical operations—version, diffcult forceps deliveries, or breech extraction through a very narrow pelvis. Therefore, cesarean section usually is substituted for them, depending on the experience and outlook of the attending physician. Recovery time from cesarean section is naturally greater than for normal vaginal delivery, as it must be considered ajor surgery.
The operation is ‘nost safely done early in labor, or before labor has begun. The doctor may instead elect to try vaginal delivery first when there is a possible difficulty: the section could then be performed after labor has begun. Many doctors believe that once a cesarean section is performed, all succeeding pregnancies will also require such deliveries for fear the earlier uterine incision scars will split open under the strain of labor. However, there are some physicians who feel that this is not necessary unless the reason for the original operation is still present, Most doctors prefer to repeat the procedure in subsequent deliveries.
Depending on the attending obstetrician, one woman may undergo any number of cesarean births. Many patients choose instead to have a simple sterilization operation performed (tying and cutting Of the Fallopian tubes so the ovum cannot be fertilized) after the third or fourth birth.
The reward has come. Months of pregnancy and hours of labor culminate as the doctor hands the baby to the mother.