Birth

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Birth

• LABOUR
• Complex mix of fetal signals and endocrine
  mechanisms in the mother.
• Fetus secretes surfactant protein which seems to
  alter maternal hormones.
• Also, the agents (progesterone, nitric oxide, and
  others) that keep the uterine muscle quiet,
  decrease, and the uterus starts to contract.

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BIRTH

• LABOUR
• Surfactin signals moms hypothalamus produced
  when fetal lungs ready to breathe

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BIRTH

• LABOUR (Contd)
• Hypothalamus stimulates pituitary
• Pituitary secretes oxytocin
• Oxytocin makes uterus contract labour begins

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BIRTH

• Other mechanisms involved in the start of labour
• CRH corticotropin-releasing hormone released by
  the placenta. Amounts correlate with date of
  labour (early, on time or post-dates) by the
  16th-20th weeks gestation
• CRH seems to trigger fetal production of
  cortisol. Cortisol clears fluid from infants
  lungs and stimulates more CRH production.
• This, in turn, stimulates placental estrogen
  production, necessary for starting labour.

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BIRTH

• SOME POSSIBLE SIGNS OF LABOUR
• Mucus plug falls out from cervix
• Amniotic fluid leaks or gushes out
• Contractions - but Braxton Hicks False Labour

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WHAT IS LABOUR?
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BIRTH

• STAGES OF LABOUR
• False labour Braxton-Hicks contractions
• First stage
• early first stage longest (hours or days), mild
  contractions, 10-30 duration _at_ 20, 15, 10, 5
  intervals
• late first stage 60-90 duration _at_ 3, 2, 1
• transition shortest, (15-30) most intense,
  random pattern of contractions.
• All along, cervix dilating and effacing (thinning)

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BIRTH

• STAGES OF LABOUR (Contd)
• Second stage
• cervix fully dilated (10 cm)
• baby moves down birth canal
• crowning
• duration primiparas about 1 hr., multiparas
  faster
• head first, rotation
• shoulders, one at a time
• rest of baby slithers out

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BIRTH

• STAGES OF LABOUR (Contd)
• Third stage
• after 10-15 interval
• expulsion of placenta
• During interval between stages 2 and 3
• lungs start to work gradually
• cord delivers last of maternal blood to infant
• heart valves close
• cord must not be cut until white and not pulsing

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BIRTH

• Birth
• empowering experience for mother
• Super-orgasm (Kitzinger)
• Gentle pushing, breathing baby out
• Mouth open leads to open introitus

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BIRTH

• POSITIONS FOR LABOUR
• Not on her back!!! Lithotomy Position
• Weight of uterus and its content on abdominal
  aorta can cause reduced blood flow to fetus
• Slows down labour
• Importance of gravitys help

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BIRTH

• POSITIONS FOR BIRTH
• Standard lithotomy one of the worst. Better
• sitting up reclined
• lying on her side
• on hands and knees
• Unmedicated, undisturbed birth best. 90-95
  births do not need intervention.

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BIRTH

• RISKS OF INDUCING LABOUR
• Contractions too hard, lead to more analgesics
  and anesthetics
• Hard contractions can also lead to uterine
  rupture and to brain damage (pressure on the
  skull)
• If lungs not ready, leads to respiratory distress
  (formerly called hyaline membrane) due to lack of
  surfactin

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BIRTH

• POSSIBLE COMPLICATIONS (5-10)
• inefficient placenta, affects fetal growth, life
  threatening for fetus
• placenta previa
• abruptio placenta
• transverse presentation
• breech presentation (feet or buttocks)
• prolapsed cord
• cord pinched or wrapped around neck

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BIRTH

• POSSIBLE COMPLICATIONS (5-10) (Contd)
• small pelvic diameter
• multiple births
• toxemia elevated BP, fluid retention, can lead
  to eclampsia (possibly fatal)
• maternal asthma

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BIRTH

• POSSIBLE COMPLICATIONS (5-10) (Contd)
• All carry risk of hypoxia or anoxia
• Hypoxia
• reduced oxygen
• Anoxia
• NO oxygen
• Consequences
• brain damage
• detectable or subclinical

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BIRTH

• POSSIBLE IATROGENIC EFFECTS OF INTERVENTION
• Common interventions
• Induction of labour (pitocin), use of pitocin to
  re-start or accelerate labour can cause too
  strong contractions, pain, uterine rupture
• Episiotomy (infections, painful sex, painful
  sitting)

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EPISIOTOMY
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BIRTH

• POSSIBLE IATROGENIC EFFECTS OF INTERVENTION
• Common interventions (Contd)
• C-section major abdominal surgery possible lack
  of adrenaline/noradrenaline in baby. N. American
  C-sec rates too high
• Pain medication (analgesics and anesthetics) can
  slow down labour and decrease oxygen delivery to
  baby

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BIRTH

• POSSIBLE IATROGENIC EFFECTS OF INTERVENTION
• Common interventions (Contd)
• Fetal monitor external or internal
• External curtails movement, mother on her back
• Internal possible damage to baby, also curtails
  mothers movement
• Forceps
• All interventions potentially iatrogenic damage
  caused by medical treatment.

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BIRTH

• EFFECTS OF ANESTHETICS AND ANALGESICS
• slow down labour (leading to pitocin use)
• sluggish baby
• mother zonked, weak
• can interfere with bonding
• can interfere with lactation
• can interfere with rooming-in

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BIRTH

• In some cultures, intercourse used to start or
  accelerate labour.
• How soon can have sex post-partum? Six weeks or
  when ready. Effect of episiotomy, C-section.
• Moms who breastfeed tend to return to sex
  earlier.
• Tiredness, lack of sleep, overwhelmed
• Change in roles, decrease of romanticism.