Method for Induced Abortion

1. Method for Induced Abortion OBSTETRICS & GYNECOLOGY Volume 104, Number 1, July 2004 R3 박영미

2. 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

3. Methods for abortion in the first trimester

4. 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 (D&E) • Antibiotics • Marked reduction in postabortal infection • Tetracycline, doxycycline, minocycline : broad spectrum of antimicrobial effect : oral absorption

5. 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 -> reduces blood loss -> prevent postabortal uterine atony • Nonsteroidal anti-inflammatory drugs • Preoperative administration -> modest reduction in pain • Conscious sedation • Intravenous midazolam 1-3mg and fentanyl 50-100ug

6. 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

7. 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

8. 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

9. 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

10. 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

11. 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 -> subside temporarily as the artery goes into spasm -> no intra-abdominal bleeding • Management • Hysterectomy • Arteriography and selective uterine artery embolization

12. 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

13. 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

14. Complications of vacuum curettage - Later complication - • Retained tissue or clot & early endometritis • Symptom & sign ① No response to simple analgesics ② Excessive and prolonged bleeding ③ Severe pain or fever • Management ① Broad spectrum oral antibiotics ② Vacuum evacuation in the clinic

15. Complications of vacuum curettage • Advanced sepsis • Symptom & sign ① generalized abdominal tenderness & guarding ② tachycardia ③ significant fever ④ prostration • Management ① immediate hospital care ② prompt uterine evacuation ③ high dose combinations of antibiotics ④ intensive care for cardiovascular support with fluid resuscitation, monitoring with central lines

16. Medical abortion in the first trimester • Three highly effective regimens • Mifeprostone (RU-486) + misoprostol • Methortexate + misoprostol • Misoprostol alone

17. Medical abortion in the first trimester • Mifepristone + prostaglandin analogue • The first highly effective means • Mifeprostone : analogue of norethindrone : high affinity for progesterone receptors -> act as a false transmitter and blocks natural progesterone • Effectiveness : increased to approximately 95% by the addition of low- dose prostaglandin

18. 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 -> lower peak serum level, more sustained blood level -> 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

19. 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 -> 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

20. 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

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

22. 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

23. 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

24. Second-trimester abortion

25. Dilation and Evacuation • Dilation of the cervix • Laminaria method : Prevailed because of ① concerns about cervical injury for mechanical dilation ② the greater technical ease of second-trimester procedures : More laminaria are used as gestational age ① After 20 weeks -> 10 more laminaria ② 10-13 laminaria at 20-23 weeks -> greater than 14mm by the next day

26. Dilation and Evacuation : Method ① Initial set of 2-3 medium laminaria ② 4 or more new laminaria to the first set 6 hours later ③ Dilatations of 18 mm or more by the next day in 92% • Misoprostol treatment : Replace laminaria in the early second trimester : method ① 600ug administered buccally ② 2-4 hours before procedure ③ At 14-16 weeks of gestation ④ Sufficient dilation to allow insertion of a 14mm vacuum curette

27. Dilation and Evacuation • Instrument technique • At 13-15 weeks : Readily evacuation with vacuum cannula of 12-14mm -> 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

28. 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

29. Dilation and Evacuation • The patients • The obese patient : Increased procedure difficulty, procedure time, blood loss with increasing body mass index : BMI greater than 30 -> 20% longer time for procedure -> 40% more difficult by the operator • Placenta previa : Not a contraindication to laminaria with D&E • Previous cesarean delivery : Not increase perioperative risk of D&E

30. Dilation and Evacuation • Intact D&E procedure ① 2 or more days of laminaria treatment to obtain wide dilation of the cervix ② Assisted breech delivery of the trunk of the fetus, under ultrasound guidance ③ The calvarium is decompressed ④ Delivered with the fetus otherwise intact

31. Dilation and Evacuation • Combination D&E technique ① After multistage laminaria treatment over 2 or more days ② 1.5-2.0mg of digoxin are injected into the fetus under ultrasound guidance ③ The membranes are ruptured ④ Intravenous oxytocin is started (167mU/min) ⑤ Assisted delivery is performed after a few hours

32. Complications of dilation and evacuation • The same as first-trimester surgical abortion : no more frequent when laminaria are used • Perforation • 0.32% for D&E 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

33. 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 D&E than with labor induction technique • Must be considered when a patient exhibits respiratory difficulty while undergoing an abortion

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

35. Labor induction methods • Intra-amniotic prostaglandin F²α • 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

36. Labor induction methods • Systemic prostaglandins • Three different prostaglandis ① Dinoprostone (prostaglandin E2) ② Carboprost tromethamine (Hemabate) ③ Misoprostol

37. 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 -> 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

38. 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

39. Labor induction methods • Mifepristone and prostaglandins • Method ① Mifepristone is administered ② 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

40. Labor induction methods • High dose oxytocin • Method ① 50 units in 500mL of 5% dextrose and normal saline given over 3 hour period ② After 1 hour rest ③ Oxytocin infusion is repeated, adding 50 additional units to the next 500mL infusuon, continuing with 3 hour ④ And 1 hour of rest ⑤ Repeat until the patient aborts or a final solution of 300 units of oxytocin in 500mL is reached

41. Labor induction methods • Use of feticidal agents • Feticidal agents : reduces the induction to abortion interval and improve efficacy • Method ① 60mL of 23% saline solution ② Intra-amniotic urea ③ Ultrasound guided fetal intra-cardiac injection of potassium chloride ④ 1.0-1.5mg of digoxin given : ultrasound-directed intrafetal injection : into the amniotic sac

42. 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

43. 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 -> 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

44. Fetal death in utero • Hemorrhage begun after abortion -> DIC should be suspected • If the uterus appears intact on manual exploration ① intramuscular carboprost, immediately : stop the bleeding, even in the presence of DIC : reduce the need for blood products ② misoprostol 1000ug rectally : used successfully for postpartum hemorrhage

45. 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 -> embolic phenomena -> infarction in the surviving twin

46. Selective fetal reduction • Fetal loss • Higher with higher starting numbers of gestations ① Starting number > 6 -> 15.4% ② Starting numbers =2 -> 6.2% • Higher if more fetuses were left intact ① Finishing number = 3 -> 18.4% ② Finishing number = 1 -> 6.7%