OBgyn Week 10

1. OBgyn Week 10 Labor & Delivery

2. Birth Practitioners Who can deliver the baby? • Obstetrician-Gynecologists • Maternal-Fetal Med Specialists • Family Practice Physicians • Midwives

3. Phases of Labor • Stage 1 (early labor and active labor) • Stage 2 (birth of baby) • Stage 3 (birth of placenta) • (Stage 4 (uterine recovery)) • Post-partum

4. Stages of Labor

5. Early Labor • What initiates labor onset? Labor initiation theories: • Baby-initiated Fetal pituitary signals fetal adrenals Adrenals secrete cortisol-type hormone Released into amniotic fluid via fetal urination Absorbed into maternal blood stream Stimulates maternal pituitary release of oxitocin Enters maternal blood stream, stimulates uterine contractions

6. Labor initiation theories Mom-initiated • Uterus reaches specific size that causes contractions due to stretching of muscle fibers (& oxytocin release) • ANS signal that stimulates contractions • Drop in progesterone right before labor removes block to uterine contractions Weather-initiated • More babies born when barometric pressure drops suddenly (eg during snow or rain storm) Most likely a combination of factors.

7. (Physiology of Labor Onset) • Physiology of cervical ripening and initiation of UC (uterine contractions) • Oxytocin produced and released by pituitary into maternal bloodstream throughout pregnancy • Large # oxytocin receptors in uterus - # of receptors grows as pregnancy progresses. • Late PG increase in oxytocin 500% due to uterine stretching and increase in E:P • Estrogen increases relative to progesterone in 2nd trimester • E increases concentration of oxytocin receptors in uterus • Affects cytokine and prostaglandin production that causes cervical ripening (soften, thin out, and dilate)

8. Labor Onset: S/Sx • Pre-labor = regular uterine contractions without cervical change • True labor = regular contractions that cause cervical change and continue until baby is born • Stalled labor = strong regular contractions with cervical change followed by halt in cervical change and descent of baby

9. Rupture of Membranes • Membrane rupture aka “water breaking” • Can occur before, during or even after baby is born • Concern for infection rises the longer it is between membrane rupture and labor • Consider prophylactic antibiotics, esp. if mom is beta-strep positive

10. Labor Onset: S/Sx • SROM= spontaneous rupture of membranes • Mom can feel fluid leak either as a gush or trickle • May be confused with urine incontinence or vaginal fluids • Fluid should be clear and smell slightly of seawater • Watch for presence of meconium in amniotic fluid: starts as dark brown/black and goes pale green over time (may indicate fetal distress) • Maintain hygiene carefully after rupture: nothing inserted into vagina, clean well after urination & bowel movements

11. Meconium • Thick, dark green, very sticky, tar-like substance that lines fetal intestines. • Not usu released until after birth • If released before birth, mixes with amniotic fluid • More chance of release if post-term • Degree of release (color of amniotic fluid) helps determine action - from monitoring only to amnioinfusion and neonatal airway suction • Aspiration of meconium can --> pnemonia

12. Meconium • Baby will normally pass meconium in first few BMs after birth • Oiling baby’s bottom beforehand can help to remove this very sticky substance

13. More S/Sx of Labor Onset • “Bloody show”: pink-tinged mucus (from a bit of blood), caused by cervical effacement and/or dilation; capillaries break and mix with mucus • Mucous plug: inner os filled with plug during PG; is usually yellowish-brown. May lose this before or during labor and is a sign that the cervix is changing • Diarrhea / loose stools as body prepares for labor • Low back and butt pain, urge to poop that is nagging and won’t go away

14. Abnormal SX to watch for • Important for mom to monitor for: • Cessation of fetal movement for > 12 hours • Any vaginal bleeding (more than Bloody Show) • Marked edema or h/a • Dizziness • Visual changes

15. Contractions During Early Labor • Pre-labor contractions vs Braxton-Hicks • B-H: usu felt in lower abd, cervix or back • Doesn’t tend to include fundus or upper abdomen • Tend to be irregular, but can get regular • Do not lead to dilation, effacement, or descent • Generally are not painful

16. Labor Progression Terminology • Dilation: distance from one side of inner os to the other side; 0-10 cm • Effacement: depth of cervix (0-100%) • Station: degree of descent; how far baby’s head is into vaginal canal (ischial spine as landmark) • Range is from -5 (above spines) to +5 (below spines: crowning) • Measured at the farthest point you can touch on either side of baby’s head (biparietal diameter)

18. Fetal Descent Stations

19. First Stage of Labor pt 1 Early phase: 0-4/ 5 cm dilation; effacement varies • Contractions at regular intervals causing dilation (interval measured from beginning of one contraction to beginning of next) • Contractions often 5-10 minutes apart, lasting 30-45 seconds; gradually getting closer and longer • Baby’s head may be descending • Woman can often talk through these, esp. early on • Mom should rest if she can to help save her energy for later • If at home, can continue to eat and drink • Good time to walk / climb stairs / do lunges / slow dance (with assistance/support)

20. First Stage of Labor pt 2 • Active phase • Starts at 4/5 cm to complete dilation • Intervals usually less than 4 minutes, duration more than 45 seconds. • Contractions much stronger, closer together • Baby should be starting to descend • Bag should be bulging with the strength of uterine contractions • Whole uterus involved in contraction in coordinated effort to push baby out.

21. Active Labor • Transition is the part of the active phase when cervix dilates from 7-10cm • Usually more painful contractions, more intense, much closer together, little rest in between • Mom may get chilly, spacey, flushed, emotional, want to be alone or have someone there for every contraction, n/v • Coaching support extremely important at this stage

22. Symptoms during Transition • Factors causing these symptoms: • Hormones: oxytocin release • Pressure on nerves • Dilation of birth canal from baby’s head • Pain medications (epidural) • Signs of 2nd stage being near: start hearing bearing-down efforts, desire to push, feel as if about to have BM (b/c pudendal nerve gets pressure which gives the urge to push)

23. Length of Labor • Labor stage length averages Amt of time labor takes all together depends upon whether she’s a first time mom or not.

24. Stage 1 • Practitioner’s activities in First stage: • Determine if labor has begun: internal vaginal exam checks for dilation, station, effacement, membranes (intact or not) • Vitals and FHT (fetal heart tones) • Enema for mom if she desires/if necessary • Baths can help relax muscles but not a good idea before 5 cm dilation because it can stall labor • Pressure or massage to back, feet, shoulders • Encouragement • In many hospital settings a L&D nurse responsible for most of these activities

25. Stage 1 • Fluids/ food • During a hospital birth, will have IV fluids/ lactated ringer’s solution (electrolytes) and ice chips • During a home birth, woman allowed to eat (simple, bland foods best) and drink water or electrolyte drink • Encourage frequent urination • If in hospital mom will have catheter • Toilet a good place to have contractions (sense of letting go, she’s used to letting go there)

26. Stage 1 - Positions • Positions • Home birth/Birth Center: allows for ambulation; help mom find comfortable positions: walking, leaning, use pillows, as long as FHT respond well to positions • Hospital: change from side to side, but confined to bed because is hooked up to IV and monitors

27. Stage 1 - Breathing • Breathing • Not very formalized anymore • Have mom breath comfortably • Lamaze breathing helps give mom/dad something to concentrate on • Make sure mom not hyperventilating or holding her breath • Premature urge to push may require coaching mom to pant to prevent pushing on the undilated cervix

28. Stage 1 • Monitor: • PE: progression of dilation, effacement, station • Duration and interval of uterine contractions • FHT: baseline is 120-160bpm, which usually change during contractions • Late deceleration: gradual decrease of FHT during contractions; drop is after peak of contraction; degree of severity is associated with the length of return to baseline • Sign that baby is not tolerating stress of contractions well

29. Stage 2 Commonly called the “pushing” stage • Two parts of 2nd stage: • Phase one: passive fetal descent • Complete dilation of cervix before pushing • Part of baby that is presenting is rotating to best possible position for delivery • Urge to bear down becomes reflexive when baby descends into pelvis • Phase two: expulsive phase • Pushing or bearing down until infant is delivered • Begins after fetus has descended and rotated into proper position

30. Stage 2 - positions • Positions: anything ok as long as it makes mom comfortable and FHT remain normal • Birth chair: advantage of gravity and can move legs • Squatting: with support under arms (1 person on either side), good for end pushes • Semi-reclined: least advantageous, good if labor is too quick as it helps slow it down • Hands and knees: helpful if pelvis small, great for shoulder dystocia • Side lying: common with epidural, slows deliver, helps prevent tearing

31. Stage 2 - positions • Advantage of upright v supine positions: upright preferred by mother, shorter 2nd stage, reduction in episiotomies, fewer FHT abnormalities • Disadvantage of upright: increase in 2nd degree lacerations • Advantages of being mobile: increased placental perfusion, optimize fetal alignment and descent, shorter 2nd stage, fewer episiotomies, lacerations and FHT abnormalities, less severe pain, squatting increases pelvic space and avoids compression of vena cava

32. Stage 2 - positions • Lateral delivery: fewer lacerations, good placental perfusion • Birthing chairs disadvantages: increased perineal edema, lacerations, and blood loss

33. Stage 2 - pushing • Premature urge to push is sometimes felt by women before complete dilation • Common with occiput posterior (OP – faced the wrong way) babies because occiput presses on rectum • Prolonged pushing can cause cervical edema, cervical laceration, and exhaustion of the mom • If baby in other positions and if dilated to 8-9 cm let woman push as her body guides her

34. Stage 2 - Fetal Heart Tones • Normal FHT patterns • FHT increases with contractions – they get a little stressed here. • Variable decelerations: FHT not matching contractions usually due to cord compression. Ok as long as baby recovers to baseline each time. • Monitor closely if • Decelerations down to 80-100 while pushing; should come back to baseline after mom stops pushing when contraction done • Abnormal FHT: change position, if no improvement, delivery necessary (or transport if at home)

35. Stage 2 - breathing • 2nd stage breathing • Have mom do what feels right • Coached pushing: Valsalva technique • Push as if having a BM • Hold breath while pushing after taking in a deep breath • Aim is for 3 pushes per contraction; longer pushes with quick breath in between are more effective than short pushes • If making noise during push, not doing it correctly • Rest in between contractions • Only push during contractions • Offer mirror for “self-directed” pushing

36. Stage 2 - support • 2nd stage coaching • Emotional support: • Encourage the mother, tell her she can do it • Decreases catecholamines due to stress, fear • Prevents decreased uterine contractions due to catecholamine release • Decreases need for pain meds • Shorter labor • Decreased need for instrumental or cesarean delivery • Supports woman’s bodily functions

37. Stage 2 - support • 2nd stage coaching techniques • Encourage woman to delay pushing until her body directs her to (difficult if epidural), usually at +1 or +2 station • Direct mother’s pushing efforts when necessary (when don’t appear to be effective) • Help her into positions of her choice, encourage changes every 20-30 minutes • Reassure her intensity of sensations are normal • Make her aware of her progress (provide feedback) b/c she can’t see what she’s doing and what’s going on.

38. Stage 2 - Labor Dystocia • Labor Dystocia or Failure to Progress • Ferguson Reflex (bearing down during contraction) may be delayed or premature • Delayed: usually contractions further apart • Let mom rest if no urge to push • Can stimulate urge by squatting, pressing on posterior vaginal wall, other techniques

39. Failure to Progress • Premature Ferguson reflex Avoid pushing if cervix not fully dilated! • Causes cervix to swell and decrease dilation • Causes intrauterine pressure to rise, decreasing fetal oxygenation • Can overstretch ligaments supporting fetus • If urge is uncontrollable, let her uterus push without using abdominal walls and diaphragm

40. Stage 2 - ease • Factors affecting length and degree of ease of 2nd stage • Strength and coordination of contractions • Strength and ability of mom’s pushing effort • Weak abdominal muscles, unwillingness to push hard, mom exhausted • Resistance of lower birth canal: outlet contraction or rigid perineum • Higher in primips • Athletes/dancers have well-toned mm which don’t relax easily • Full bladder or rectum • Malpresentations

41. Induction of Labor • 5% of primips do not have natural cervical ripening and may require induction • Several methods to do so: • Herbs, acupuncture, homeopathy (Gelsemium) • Breast stimulation, foley catheter, prostaglandin gel on cervix, stripping of membranes, amniotomy (artificial rupture of membranes) • IV pitocin

42. Induction of Labor • Over 60% of labors in US are induced • C-section rate in hospital for failed inductions around 60% • Indications: • Post dates • PROM • PIH • Fetal distress • Significant antepartum hemorrhage • Macrosomia (very large baby) • Patient or doctor convenience – weird western convenience thing.

43. Contraindications to Induction of Labor • True CPD (cephalopelvic disproportion – rare – head “too large” to exit cervix. Measure pelvic spines to determine.) • Abnormal presentation which prevents vaginal delivery • High station • Fetal distress • Placenta previa – placenta across cervical opening • Cord presentation • Invasive carcinoma of the cervix • Gestational age <37 weeks or >42/43 weeks (primip/multip)

44. Stage 2 - Delivery • Progress checked with sterile glove • Perineal stretching with mineral or olive oil: massage from internal introitus with two fingers • Also good to do prenatally in last 6 weeks of pregnancy, 5 min daily • Minimizes tearing at delivery • Also hot compresses (add betadine to hot water) hold on perineum and intoritus during or between contractions

45. Delivery - perineal stretch • Delivery of the head should be slow to give the perineum time to stretch • Counter pressure with flexion of baby’s head toward perineum and away from urethra and clitoris • Have mom moan during contraction (instead of holding breath) to help slow down delivery

46. Delivery - cord check • Check for cord after delivery of the head • Nuchal cord is when the umbilical cord is over head and around neck • If enough slack, can be lifted around head • Special maneuvers to deliver through cord • Cord can be clamped and cut early if necessary • Baby needs to be delivered quickly if cord around neck

47. Delivery of Head

48. Delivery - body • After head is delivered, ideally the rest of the baby should be out on the next contraction if possible • Restitution: baby usually rotates on its own so that shoulders can be delivered

49. Delivery - care of infant • Immediate baby care • Skin-to-skin contact with mom will help with temperature regulation, bonding, and vitality • Have ready: bulb syringe, blanket, cord clamp kit • Drying off baby can stimulate breathing, circulation • Suction baby’s nose and mouth • Baby wrapped in clean blanket, hat put on (cannot regulate body temp well first few days of life) • Less focus these days on removing vernix (coating around the baby – very moisturizing)

50. Neonate