Method for Induced Abortion

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Method for Induced Abortion

• OBSTETRICS GYNECOLOGY
• Volume 104, Number 1, July 2004
• R3 ???

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• First trimester abortion
• Vacuum curettage
• Complications of vacuum curettage abortion
• Medical abortion in the first trimester
• Complications of early medical abortion
• Second trimester abortion
• Dilation and evacuation
• Complications of dilation and evacuation
• Labor induction methods
• Fetal death in utero
• Selective fetal reduction

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Methods for abortion in the first trimester
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Vacuum curettage

• The most common method of abortion in the United
  States
• Before 13 weeks suction or vacuum curettage
• After 13 weeks dilation and evacuation (DE)
• Antibiotics
• Marked reduction in postabortal infection
• Tetracycline, doxycycline, minocycline
• broad spectrum of antimicrobial effect
• oral absorption

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Vacuum curettage

• Pain relief
• Paracervical block
• 10-20mL of 1 lidocaine
• Deep injection into the cervical stroma at
  multiple site
• Addition of 2-4 units of vasopressin to the
  anesthetic solution
• -gt reduces blood loss
• -gt prevent postabortal uterine atony
• Nonsteroidal anti-inflammatory drugs
• Preoperative administration -gt modest reduction
  in pain
• Conscious sedation
• Intravenous midazolam 1-3mg and fentanyl 50-100ug

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Vacuum curettage

• The necessary dilatation of the cervix
• Mechanical cervical dilation with tapered
  cervical dilators
• Hygroscopic dilators laminaria
• Reduces risk for perforation or cervical
  laceration
• Prostaglandins misoprostol
• 400ug vaginal dose, 3-4 hours before procedure
• Minimal side effects, little expense

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Vacuum curettage

• For complete abortion and early diagnosis of
  ectopic pregnancy
• Preoperative ultrasonography
• Careful inspection of the aborted tissue
• Follow up with serial hCG titer
• Manual vacuum aspiration
• 6mm flexible cannula and modifed 60ml syringe
• Effective in pregnancies as early as 3 weeks
• As safe and effective as electric vacuum through
  10weeks of pregnancy
• Used to treat Incomplete spontaneous abortion in
  office or emergency room

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Complications of vacuum curettage

• - Immediate complications -
• Excessive bleeding
• Cause
• Incomplete abortion
• Pregnancy of more advanced gestational age than
  expected
• Uterine atony
• Low-lying implantation
• Uterine injury
• Management
• Misoprostol 1000ug, rectally or buccally
• 30ml balloon Foley catheter inserted into the
  uterine cavity, inflated with 50-60ml of sterile
  saline

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Complications of vacuum curettage

• Persistent postabortal bleeding
• Cause
• Retained tissue or clot (hematometra)
• Trauma
• Management
• Prompt surgical intervention
• laparoscopy
• repeat vacuum curettage
• Selective uterine artery embolization
• Rarely, hysterectomy

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Complications of vacuum curettage

• Uterine perforation
• Risk
• 1 in 1000 first trimester abortion
• Increases with gestational age, parous women
• Perforations at the junction of the cervix and
  lower uterine segment
• lacerate the ascending branch of the uterine
  artery within the broad ligament
• severe pain, broad ligament hematoma,
  intra-abdominal bleeding
• laparotomy to ligate the severed vessels and
  repair the uterine injury

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Complications of vacuum curettage

• Low cervical perforation
• Injure the descending branch of the uterine
  artery within the cardinal ligaments
• The bleeding is external, through the cervical
  canal
• -gt subside temporarily as the artery goes into
  spasm
• -gt no intra-abdominal bleeding
• Management
• Hysterectomy
• Arteriography and selective uterine artery
  embolization

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Complications of vacuum curettage

• Hematometra
• Symptom sign
• Lower abdominal pain
• increasing intensity in the hour after an
  abortion
• Large, globular, tense uterus
• Management
• Immediate re-evacuation
• Pretreatment with ergot 0.1mg IM, the use of
  oxytocin
• Addition of vasopressin to the paracervical
  anesthetic

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Complications of vacuum curettage

• Early detection of ectopic pregnancy, incomplete
  abortion
• Immediate fresh examination of the specimen
• The gestational sac, chorionic villi are easily
  visualized
• If no chorionic tissue
• Frozen section to rule out ectopic pregnancy
• A few villi but no gestational sac
• Retained pregnancy tissue in the uterus

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Complications of vacuum curettage

• - Later complication -
• Retained tissue or clot early endometritis
• Symptom sign
• ? No response to simple analgesics
• ? Excessive and prolonged bleeding
• ? Severe pain or fever
• Management
• ? Broad spectrum oral antibiotics
• ? Vacuum evacuation in the clinic

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Complications of vacuum curettage

• Advanced sepsis
• Symptom sign
• ? generalized abdominal tenderness guarding
• ? tachycardia
• ? significant fever
• ? prostration
• Management
• ? immediate hospital care
• ? prompt uterine evacuation
• ? high dose combinations of antibiotics
• ? intensive care for cardiovascular support
  with
• fluid resuscitation, monitoring with
  central lines

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Medical abortion in the first trimester

• Three highly effective regimens
• Mifeprostone (RU-486) misoprostol
• Methortexate misoprostol
• Misoprostol alone

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Medical abortion in the first trimester

• Mifepristone prostaglandin analogue
• The first highly effective means
• Mifeprostone
• analogue of norethindrone
• high affinity for progesterone receptors
• -gt act as a false transmitter and blocks
  natural
• progesterone
• Effectiveness
• increased to approximately 95 by the
  addition of low-
• dose prostaglandin

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Medical abortion in the first trimester

• The U.S FDA
• Mifepristone 600mg orally, followed by
• misoprostol 400ug orally 2days later
• Use is limited to the first 49days of
  amenorrhea
• Evidence-based protocol
• Mifeprostone 200mg orally, followed by self-
• administered vaginal misoprostol 800ug at
  home
• Vaginal misoprostol -gt lower peak
  serum level, more sustained blood level
• -gt administered at 24,48,72 hours after the
  mifeprisotne
• (no difference in efficacy)
• The effective gestational age can be safely
  
• extended from 49 to 63 days of amenorrhea

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Medical abortion in the first trimester

• Methotrexate misoprostol
• Regimen
• Methotrexate 50mg/m2 single intramuscular
  dose,
• followed vaginal imsoprostol 800ug at 3-7days
  
• Expulsion of the gestational sac has not
  occurred
• -gt Misoprostol is repeated in 24hours
• Effectiveness
• 53 aborted after the first dose of
  misoprostol,
• additional 15 after the second dose,
• total of 92 by 35 days

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Medical abortion in the first trimester

• Misoprostol alone
• Regimen
• Vaginal misoprostol 800ug initially,
  followed by
• 800ug at 24 hours, if needed
• Effectiveness
• Complete abortion rate 92
• As effective as mifepristone/misoprostol and
  
• much less expensive

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Medical abortion in the first trimester

• Vaginal ultrasonography after start of medical
  abortion
• Performed to ensure that the uterine cavity is
  empty
• Intact gestation with cardiac echoes 2weeks after
  start of medication -gt failed abortion
• Gestational sac is present but no fetal cardiac
  activity
• -gt wait for expulsion, take more misoprostol
  
• -gt have surgical evacuation
• If medical abortion fails, surgical termination
  is advisable
• possible risk for fetal malformation from
  misoprostol and
• methotrexate

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Complications of early medical abortion

• Persistent bleeding
• The duration of bleeding or spotting
• 9-16 days after mifeprisotne/ misoprostol
• up to 8 as long as 30 days
• Need for curettage is related to gestational age
• ( 200mg mifepristone 800ug vaginal
  misoprostol )
• 2.1 at 49 days or less
• 3.1 at 50-56 days
• 5.1 at 57-63 days

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Complications of early medical abortion

• Hausknecht the complications report
• ( November 2000 to May 2002, 80,000 women who
  received
• mifepristone )
• Vacuum curettage for bleeding or for persistent
  non-viable pregnancy
• A death of a woman with a ruptured ectopic
  pregnancy
• Infection (0.013)
• Sepsis with adult respiratory distress syndrome
• Coronary artery thrombosis

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Second-trimester abortion
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Dilation and Evacuation

• Dilation of the cervix
• Laminaria method
• Prevailed because of
• ? concerns about cervical injury for mechanical
  dilation
• ? the greater technical ease of
  second-trimester
• procedures
• More laminaria are used as gestational age
• ? After 20 weeks -gt 10 more laminaria
• ? 10-13 laminaria at 20-23 weeks
• -gt greater than 14mm
  by the next day

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Dilation and Evacuation

• Method
• ? Initial set of 2-3 medium laminaria
• ? 4 or more new laminaria to the first set 6
  hours later
• ? Dilatations of 18 mm or more by the next day in
  92
• Misoprostol treatment
• Replace laminaria in the early second
  trimester
• method
• ? 600ug administered buccally
• ? 2-4 hours before procedure
• ? At 14-16 weeks of gestation
• ? Sufficient dilation to allow insertion of a
  14mm vacuum
• curette

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Dilation and Evacuation

• Instrument technique
• At 13-15 weeks
• Readily evacuation with vacuum cannula of
  12-14mm
• -gt Ovum forceps (as an adjunct)
• The surgeon may prefer to use forceps as the
  primary and
• use the vacuum only the end of the procedure
• Through 16 weeks
• The 16mm cannula system, vacuum curette
  alone
• At 17 weeks and beyond
• Even large diameter aspiration system is not
  adequate by
• itself
• Forceps evacuation ,the primary method and
• vacuum, the secondary method

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Dilation and Evacuation

• Decrease of blood loss
• Intravenous oxytocin
• 40 or more units per 1000mL
• During the procedure or begun after uterine
  
• evacuation is completed
• Vasopressin
• Two to four units mixed with the local
  anesthetic
• solution
• Diluted with 10-20mL sterile saline
• Injected into the cervix

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Dilation and Evacuation

• The patients
• The obese patient
• Increased procedure difficulty, procedure
  time,
• blood loss with increasing body mass index
• BMI greater than 30
• -gt 20 longer time for procedure
• -gt 40 more difficult by the operator
• Placenta previa
• Not a contraindication to laminaria with DE
• Previous cesarean delivery
• Not increase perioperative risk of DE

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Dilation and Evacuation

• Intact DE procedure
• ? 2 or more days of laminaria treatment to obtain
  wide dilation of the cervix
• ? Assisted breech delivery of the trunk of the
  fetus,
• under ultrasound guidance
• ? The calvarium is decompressed
• ? Delivered with the fetus otherwise intact

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Dilation and Evacuation

• Combination DE technique
• ? After multistage laminaria treatment over 2 or
• more days
• ? 1.5-2.0mg of digoxin are injected into the
  fetus
• under ultrasound guidance
• ? The membranes are ruptured
• ? Intravenous oxytocin is started (167mU/min)
• ? Assisted delivery is performed after a few hours

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Complications of dilation and evacuation

• The same as first-trimester surgical abortion
• no more frequent when laminaria are used
• Perforation
• 0.32 for DE at 13-20 weeks
• but, 0.05 with first-trimester vacuum
  curettage
• Lead to bowel injury and require laparotomy
• but, safely managed with laparoscopy with first
  trimester

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Complications of dilation and evacuation

• Hemorrhage
• Caused by incomplete procedure, uterine atony,
  trauma (as in the first trimester)
• At the later gestational ages, risk for DIC
  increases
• 8 / 100,000 first trimester
• 191 / 100,000 second trimester
• Amniotic fluid embolism
• Rare and less frequent with vacuum curettage and
  DE than with labor induction technique
• Must be considered when a patient exhibits
  respiratory difficulty while undergoing an
  abortion

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Labor induction methods

• Hypertonic solution
• Intra-amniotic hypertonic saline
• The first effective labor induction method
  for
• second trimester abortion
• Hypertonic urea
• Potentially safer agent
• gt intravascular injection would not be harmful
• Intra-amniotic dose of 80-90g is effective
• injection-to-abortion intervals are
  prolonged

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Labor induction methods

• Intra-amniotic prostaglandin F²a
• Effective, but often required a second injection
• Associate with
• Transient fetal survival in some cases
• Significant gastrointestinal side effects
• Failure of the primary technique
• Risk for cervical rupture, in the
  primigravida
• Overnight treatment with laminaria tents reduced
• The mean time from instillation to abortion
  from
• 29 hours to 14 hours
• The need for second injections

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Labor induction methods

• Systemic prostaglandins
• Three different prostaglandis
• ? Dinoprostone (prostaglandin E2)
• ? Carboprost tromethamine (Hemabate)
• ? Misoprostol

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Labor induction methods

• Dinoprostone
• 20mg vaginal suppository every 3 hours
• The mean time to abortion 13.4 hours
• 90 aborting by 24 hours
• Reducing the dinoprostone to 10mg at 6 hour
  intervals combined with high-dose oxytocin
• -gt the same efficacy but fewer
  gastrointestinal side
• effects
• Carboprost tromethamine
• 250ug every 2 hours intramuscular injection
• The mean time to abortion 15-17 hours
• About 80 aborting by 24 hours

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Labor induction methods

• Misoprostol
• The ideal dose and interval is still under
  investigation
• 200ug vaginally every 12 hours
• Equally effective with dinoprostone 20mg
  every 3 hours
• Fewer side effects (vomiting, diarrhea,
  fever)
• 200ug, 400ug, 600ug at 12 hour intervals
• Abortion by 48 hours to be 70.6, 82, 96
• Vomiting, diarrhea, fever increased with the
  dose
• High doses and short intervals
• increase risk for uterine rupture
• 3 case of uterine rupture with previous
  cesarean delivery

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Labor induction methods

• Mifepristone and prostaglandins
• Method
• ? Mifepristone is administered
• ? 3 days later the patient is hospitalized for
  
• prostaglandin treatment
• (gemeprost, misoprostol)
• Typical intervals from start of the prostaglandin
  to abortion 7-9 hours
• Recent studies use misoprostol more often
• low cost and high efficacy

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Labor induction methods

• High dose oxytocin
• Method
• ? 50 units in 500mL of 5 dextrose and normal
• saline given over 3 hour period
• ? After 1 hour rest
• ? Oxytocin infusion is repeated, adding 50
• additional units to the next 500mL
  infusuon,
• continuing with 3 hour
• ? And 1 hour of rest
• ? Repeat until the patient aborts or a final
  solution
• of 300 units of oxytocin in 500mL is reached

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Labor induction methods

• Use of feticidal agents
• Feticidal agents
• reduces the induction to abortion interval and
  improve efficacy
• Method
• ? 60mL of 23 saline solution
• ? Intra-amniotic urea
• ? Ultrasound guided fetal intra-cardiac
  injection
• of potassium chloride
• ? 1.0-1.5mg of digoxin given
• ultrasound-directed intrafetal
  injection
• into the amniotic sac

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Labor induction methods

• Hysterotomy and hysterectomy
• Little indication as the primary method for
  abortion
• because the risk of major complications and
• death is greater than for any other
  technique
• The only need for hysterotomy in failed abortion
• uterine anomaly

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Fetal death in utero

• Vaginal Prostaglandine E2
• Highly effective after fetal death
• Producing fetal abortion in about 10 hours
• Side effect vomiting, diarrhea, fever
• Beyond 24 weeks, the full dose of 20mg should not
  be used -gt uterine rupture
• Misoprostol
• Increasingly used to manage fetal death
• Vaginal 200ug at 12 hour intervals
• Safe and effective in the second trimester
• The dose should be reduced in the third trimester
• Initial dose of 25ug at 6 hour intervals
• Increasing to a maximum of 50ug at 6 hour
  intervals

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Fetal death in utero

• Hemorrhage begun after abortion
• -gt DIC should be suspected
• If the uterus appears intact on manual
  exploration
• ? intramuscular carboprost, immediately
• stop the bleeding, even in the presence
  of DIC
• reduce the need for blood products
• ? misoprostol 1000ug rectally
• used successfully for postpartum
  hemorrhage

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Selective fetal reduction

• Method
• US guided intra-cardiac injection of potassium
• Indication
• Multiple pregnancy, to avoid the risk of extreme
  prematurity for the surviving pregnancies
• One anomalous fetus of multifetal gestation
• Contraindication
• Monoamniotic twins
• Twin-twin transfusion syndrome
• -gt embolic phenomena
• -gt infarction in the surviving twin

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Selective fetal reduction

• Fetal loss
• Higher with higher starting numbers of gestations
• ? Starting number gt 6 -gt 15.4
• ? Starting numbers 2 -gt 6.2
• Higher if more fetuses were left intact
• ? Finishing number 3 -gt 18.4
• ? Finishing number 1 -gt 6.7