Abnormal Labor

1. Abnormal Labor Barbara M. O’Brien, M.D. Maternal Fetal Medicine Clinical Genetics Women and Infants Hospital Brown University

2. Abnormal Labor • Dystocia: difficult labor • characterized by abnormally slow progress of labor • common whenever there is disproportion between the presenting part of the fetus and the birth canal

3. Abnormal Labor • Dystocia: • can result from several distinct abnormalities • involving the cervix, uterus, fetus, maternal bony pelvis, or other obstructions in the birth canal.

4. Abnormal Labor • Consequence of 4 distinct abnormalities that may exist singly or in combination: • (1) Abnormalities of the expulsive forces- - -either uterine forces insufficiently strong to efface and dilate the cervix (uterine dysfunction) • inadequate voluntary muscle effort during the second stage

5. Abnormal Labor • (2) Abnormalities of the maternal bony pelvis- that is, pelvic contraction • (3) Abnormalities of presentation, position, or development of the fetus • (4)Abnormalities of soft tissues of the reproductive tract that form an obstacle to fetal descent

6. Abnormal Labor • ACOG simplified these abnormalities to: • (1) Abnormalities of the powers (uterine contractility and maternal expulsive effort) • (2) Abnormalities of the passenger (fetus) • (3) Abnormalities of the passage (the pelvis)

7. Abnormal Labor • Common Clinical Findings in Women with Ineffective Labor: • Inadequate cervical dilation or fetal descent • protracted labor-slow progress • arrested labor-no progress • inadequate expulsive effort-ineffective “pushing”

8. Abnormal Labor • Fetopelvic disproportion • excessive fetal size • inadequate pelvic capacity • malpresentation or position of the fetus • Ruptured membranes without labor

9. Abnormal Labor • failure to progress :lack of progressive cervical dilation or fetal descent • cephalopelvic disproportion: obstructed labor due to disparity between fetal head and maternal pelvis • cesarean delivery is necessary with both cases

10. Abnormal Labor • Friedman curve: subdivided labor into phases and depicted it onto curves • Divides 1st stage into • latent and active phase

11. Abnormal Labor • latent phase: onset of labor is defined according to Friedman as the point at which the mother perceives regular contractions • regular contractions take place along with cervical softening and effacement • prolonged latent phase: defined as greater than 20 hours in a nullipara and greater than 14 hours in a parous woman

12. Abnormal Labor • Active phase: • cervical dilation rate of 1.2 cm/hr for nulliparas and 1.5 cm/hr for parous women • cervical dilation of 3 or 4 cm or more, in the presence of uterine contractions can be taken to reliably represent the threshold for active labor • nullipara on average dilate 1.2 cm/hour and multips on average dilate 1.5 cm/hour (minimum)

13. Abnormal Labor • Active Phase Cont’d: • Protraction: slow rate of cervical dilation or descent • For nulliparas: <1.2 cm dilatation/hr or < 1 cm descent/hr • For multiparas: <1.5 cm dilatation/hr or <2 cm descent/hr • Treat with expectant management/oxytocin • Arrest: complete cessation of dilatation or descent • Arrest of dilatation: 2 hours with no cervical change • Arrest of descent: 1 hour without fetal descent

14. Abnormal Labor • Second Stage: begins when cervical dilation is complete and ends with expulsion of fetus • Median duration for nullips: 50 min • Until recently, limited to 2 hours without epidural and to 3 hours with epidural • Median duration for multips: 20 min • Until recently, limited to 1 hour without an epidural and to 2 hours with an epidural • Can be longer with bigger babies and regional anesthesia

15. Abnormal Labor • interventions other than cesarean delivery must be considered before resorting to this method of delivery for failure to progress • i.e operative vaginal delivery

16. Abnormal Labor • Diagnosis of Inadequate Labor: • Active phase disorders: • (1)Protraction disorders • (2)arrest disorders

17. Abnormal Labor • Before the diagnosis of arrest during the first stage of labor is made, both these criteria must be met: • Latent phase has been completed, with the cervix dilated 4 cm or more • A uterine contraction pattern of 200 Montevideo units or more in a 10-minute period has been present for 2 hours without cervical change

18. Should there be a “2 hour” Rule? • Rose et al (1999) recently challenged the “2 hour” rule on the grounds that a longer time, i.e. 4 hours is necessary before concluding that the active phase of labor has failed and William Obstetrics agrees

19. Abnormal Labor • Causes of inadequate expulsive forces: • Heavy sedation or conduction analgesia • Maternal exhaustion • Maternal Effects of Dystocia: • Intrapartum infection– especially in the setting of ROM • Uterine rupture– esp with prior C/S • Fistula formation • Pelvic floor injury • Fistula formation

20. Abnormal Labor • Fetal Effects of Dystocia: • Caput Succedaneum: • If the pelvis is contracted during labor a large caput succedaneum frequently develops on the most dependent part of the fetal head • This can lead to diagnostic errors; the caput can reach almost to the pelvic floor while the head is still not engaged • An inexperienced physician may make premature and unwise attempts at forceps delivery

21. Abnormal Labor • Fetal Head Molding: • Under the pressure of the strong uterine contractions, cranial plates overlap one another at the major sutures,a process referred to as molding

22. Abnormal Labor • In nearly 97% of pregnancies, at the time of delivery, the fetus is entering the pelvis as a cephalic presentation • Compound presentation: an extremity prolapses alongside the presenting par, with both presenting in the pelvis simultaneously (1/700) • Persistent occiput posterior position: most often undergoes spontaneous rotation to anterior rotation followed by NVD

23. Cesarean section • proceed with c/s with: • Transverse lie • Placenta previa • Non-reassuring fetal heart rate when an operative delivery is not attainable • Nonvertex presenting twin • Breech • Many more indications, including repeat s( decline TOL) ands elective cesarean section

24. Cesarean Section

25. Cesarean Section

26. Maternal indications Need to avoid voluntary maternal expulsive efforts (e.g., the mother has cardiac or cerebrovascular disease) Inadequate maternal expulsive efforts Maternal exhaustion or lack of cooperation Fetal indications Nonreassuring fetal heart tracing Prolonged second stage of labor Failure to progress in second stage of labor Indications for Vacuum-Assisted Delivery

27. Vacuum extractors Easier to learn Quicker delivery Less maternal genital trauma Less maternal discomfort Fewer neonatal craniofacial injuries Less anesthesia needed Forceps Fewer neonatal injuries, including cephalohematoma, retinal hemorrhage and transient lateral rectus palsy Higher rate of successful vaginal delivery Comparative Advantages of Vacuum Extractors and Forceps

28. Vacuum

29. Vacuum

30. Procedure Using Soft-Cup Vacuum Extraction • Empty bladder • Ensure complete dilation • Adequate anesthesia • fetal presentation, position and station are then confirmed

31. How to Apply a Vacuum • apply the soft cup by spreading the patient's labia, compressing the cup and inserting it gently by pressing inward and downward with the inferior edge over the posterior fourchette. • When contact is made with the fetal scalp, the center of the cup should be over the sagittal suture and about 3 cm (1.2 in) in front of the posterior fontanelle. As a practical guide, the cup is generally placed as far posteriorly as possible

32. How to Apply a Vacuum • Avoid anterior fontanelle • Do not attempt for more than 20 minutes. • The procedure should be abandoned if delivery is not achieved or the labor does not progress. • Under ordinary circumstances, the procedure should be abandoned after three cup detachments.

33. What are some complications of the Vacuum? • Fetal complications: • Subgaleal hemorrhage: • occurred in 1.0 to 3.8 percent of vacuum extractions in one series but has been much less common in more recent studies. • Infants with subgaleal hemorrhage present with a boggy scalp, swelling crossing the suture lines and an expanding head circumference. • may also have signs of hypovolemia, pallor, tachycardia and a falling hematocrit.

34. What are some complications of the Vacuum? • Fetal Complications • Cephalohematoma • incidence of 6 percent (range: 1 to 26 percent) in vacuum-assisted deliveries. • Intracranial hemorrhage • one of every 860 vacuum-assisted deliveries compared with one of every 1,900 spontaneous deliveries (a statistically significant difference). • the comparative rate of intracranial hemorrhage is not statistically different when vacuum extraction, forceps delivery and cesarean section during labor are compared. • Perhaps the abnormal labor that necessitated the assisted delivery may be an underlying cause for a portion of the morbidity attributed to operative deliveries.6

35. What are some complications of the Vacuum? • Retinal hemorrhages • may be more common in vacuum-assisted deliveries but are most often associated with duration of labor • resolve within several weeks and are to be associated with long-term morbidity. Transient neonatal lateral rectus paralysis found to occur in: * 3.2% of vacuum-assisted deliveries * 2.4 percent of forceps assisted deliveries * 0.1 percent normal spontaneous vaginal deliveries * 0% cesarean sections (0 percent * the paralysis resolves spontaneously and is unlikely to be of clinical importance (0.1 percent)

36. Vacuum • Vacuum extraction has not been found to result in significant intellectual or neurologic disability!

37. Relative Contraindications for Vacuum Extraction • Fetal prematurity (<34 weeks of gestation) Fetal scalp trauma Unengaged head Incomplete cervical dilatationActive bleeding or suspected fetal coagulation defects Suspected macrosomia • Nonvertex presentation or other malpresentation Cephalopelvic disproportion Delivery requiring rotation or excessive traction Inadequate anesthesia

38. Forceps • Forceps are metal surgical instruments, similar to tongs, with rounded edges that fit around the fetus's head.

39. Forceps Delivery

40. Forceps

41. Technique of Applying low and outlet forceps • Identify blades and their application • The instrument should be placed in front of the pelvis with the tip pointing upward and pelvic curve forwards • First the left blade should be applied guided by the right hand and then the right blade with the left hand • Locking of blades: the blades should articulate with ease

42. Technique of Applying low and outlet forceps • Clinical checks for correct forceps applications: • Sagital suture lies in the midline of the shanks • The operator is unable to place more than a fingertip between the fenestration of the blade and the fetal head on either sidethe posterior fontanelle is not more than one finger breathe above the plane of the shanks of the forceps

43. Complications of Forceps • Mostly due to poor application • Maternal: • Extension of episiotomy or cervical tears • PP hemorrhage due to trauma • Anesthesia hazards

44. Complications of Forceps • Fetal: • Poor oxygenation • Trauma • Intracranial hemorrhage • Cephalohematoma • Facial palsy • Skull fracture • Injury to soft tissue of face

45. Breastfeeding • Infant feeding practices have changed dramatically during this century • In the early 1900s, nearly 100% of the newborns in the U.S. were breastfed • By the 1970s, only 30% of the newborn were breastfed at one week and less than 5% at 6 months

46. Breastfeeding • Breastfeeding is recognized as the best method for promoting healthy growth and development and successful bonding between mother and child • the decline in breastfeeding has been particularly problematic in developing countries • formula is expensive

47. Breastfeeding • As of 1992 about 50% of all US infants were breastfed initially and nearly 20% continued to breastfeed at 6 mo • BENEFITS OF BREASTFEEDING: • Many moms find it a wonderful and challenging experience • Mothers who breastfeed often frequently establish a stronger and faster let-down response and may ensure healthy uterine involution due to oxytocin release

48. Breastfeeding • Practical Benefits: • Low cost • Convenient and readily available in the correct quantity, at the right temperature, and without the need for complicated sterilizing and preparation procedures • Benefits to Infant’s Health: • Provides nourishment in a form that is easier for babies to digest than formula • Provides exactly the the right combination of nutrients: • Lactose as primary source of carbohydrates provides energy and correct balance of intestinal acids • Fat levels in breast milk are better digested and cholesterol levels in breast milk may protect infant from excessively high cholesterol later

49. Breastfeeding • Benefits to Infant’s Health: • Protein levels in early breast milk, especially colostrum, are vital to infant’s nutritional needs and more easily used than proteins in formula • High water content and low salt levels in breast milk ensure that infant does not need supplementary water to prevent dehydration and excrete salt • Vitamin supplements: except, occasionally vit D, are unnecessary for breastfed infants • Mineral content of breast milk is perfectly balanced and more easily absorbed

50. Breastfeeding • Benefits to Mother’s Health: • Lactation helps the mother get back in shape following pregnancy in part because milk production consumes fat reserves built up during pregnancy • Breastfeeding-induced release of oxytocin helps the uterus to contract normally postpartum