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295 SPONTANEOUS ABORTION Spontaneous abortion (miscarriage) is the termination of pregnancy before completion of the 20th gestational week. The term applies to both live and stillborn fetuses weighing Յ500 g. However, a fetus need not be identified if other products of conception are present (e.g., placenta or membranes). Familiarity with the local legal def- inition is mandatory because there is considerable state to state variation. Loss of pregnancy is very common. Recent estimates are that only 62.5% of pregnancies result in live births, 21.9% end in legal abortions, 13.8% have spontaneous abortions, 1.3% are ectopic gestations, and 0.5% end in fetal deaths. Other estimates place spontaneous abortion at 15%–40%. The earlier in gestation, the more likely is spontaneous abortion. About 75% occur before 16 weeks, and approximately 60% occur before 12 weeks. A major difficulty in detailing exact numbers is the variability of methods for pregnancy diagnosis. For example, a serum beta-subunit hCG determination will detect very early pregnancies (and thus more losses) than the available standard urine pregnancy tests. At least 80% of all pregnancies terminate spontaneously before the woman or physician is aware of the pregnancy (subclinical or undiagnosed spontaneous abortion). Table 10-1 estimates the losses with in vitro fertilization (which would be included in the subclinical category). Mortality is rare (0.7 per 100,000) with spontaneous abortion, but risk factors include: women age Ͼ35 years, races other than white, and abortion in the second trimester. Direct causes of deaths include: infection (ϳ59%), hemorrhage (18%), embolism (13%), complications from anesthesia (5%), and other (5%). Disseminated intravascular coagulation complicates many of the cases proceed- ing to death. 10 EARLY PREGNANCY COMPLICATIONS CHAPTER Copyright 2001 The McGraw-Hill Companies. Click Here for Terms of Use. BENSON & PERNOLL’S 296 HANDBOOK OF OBSTETRICS AND GYNECOLOGY ABORTION DEFINITIONS Many different variables apply to abortion, and a number of definitions are required. It is assumed that all definitions refer to spontaneous abortion, if not otherwise specified. Early abortion occurs Ͻ12th gestational week. Late abortion occurs between 12 and 20 weeks gestation. Threatened abortion refers to intrauterine bleeding Ͻ20th week of completed gestation, with or without uterine contraction, without cervical dilatation, and without expulsion of the products of conception (POC). Moreover, ultrasound must reveal the fetus to show signs of life (e.g., heartbeat or motion). In threatened abortion, the previable gestation is in jeopardy, but the pregnancy continues. Inevitable abortion is intrauterine bleeding before the 20th completed gestational week, with continued cervical dilatation but without expulsion of the POC. In inevitable abortion, momentary evacuation of part or all of the conceptus is likely. Abortion is con- sidered inevitable with two or more of the following: ● Moderate effacement of the cervix ● Cervical dilatation Ͼ3 cm ● Rupture of the membranes ● Bleeding for Ͼ7 days ● Persistence of cramps despite narcotic analgesics ● Signs of termination of pregnancy (e.g., absent mastalgia) Incomplete abortion is the expulsion of some but not all of the POC Ͻ20th completed gestational week. Complete abortion is expulsion of all the POC Ͻ20th completed gestational week. When the entire conceptus has been expelled, pain ceases, but slight spotting persists for a few days. TABLE 10-1 IN VITRO FERTILIZATION LOSSES ● 16% of fertilized ova do not divide ● 15% of fertilized ova are lost before implantation (first gestational week) ● 27% are lost during implantation (second gestational week) ● 10.5% are lost following the first missed menses ● Total loss is 68.5% Missed abortion is death of the embryo or fetus Ͻ20th completed gestational week, but the POC are retained in utero for Ն8 weeks. Symptoms of pregnancy disappear, and there may be a brownish vaginal discharge but no free bleeding. Pain and tenderness are absent, the cervix is semifirm and closed or only slightly patulous, the uterus becomes smaller and irregularly softened, and the adnexa are normal. Fetal death at 18–26 weeks followed by missed labor and retention for Ͼ6 weeks may be associated with maternal fibrinogen depletion (dead fetus syndrome). Consider administration of cryoprecipitate to prevent hemorrhage from hy- pofibrinogenemia before evacuation of the uterus (Fig. 10-1). CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 297 FIGURE 10-1. Top. Complete abortion. At right, product of complete abortion. Bottom. Incomplete abortion. At right, product of incomplete abortion. BENSON & PERNOLL’S 298 HANDBOOK OF OBSTETRICS AND GYNECOLOGY Infected abortion is that associated with infection of the internal genitalia. Septic abortion is infected abortion with dissemination of bac- teria via the maternal circulation. Habitual abortion is the spontaneous, consecutive loss of 3 or more nonviable pregnancies. Induced abortion is the purposeful interruption of pregnancy by medical or surgical techniques. ETIOLOGY OF SPONTANEOUS ABORTION EARLY ABORTION Abnormal products of conception are the overwhelming cause of spontaneous abortion. At least 10% of human conceptuses have chromosomal abnormalities, and most of these are aborted. Indeed, 50%–64% of first trimester spontaneous abortions have an abnormal karyotype (vs. ϳ7% in elective induced abortion). The most common karyotypic abnormalities are autosomal trisomy (52%– 62%), triploidy (16%), monosomies (11%–15%), and tetraploidy (4%). The single most common karyotypic anomaly is trisomy 16 (19%). The aneuploidies most commonly associated with spontaneous abortion occur in the following chromosomes: XY, 13, 14, 15, 16, 18, 21, and 22. Major interruptions of embryogenesis (e.g., failure of the fetus to develop or neural tube defects) account for some of the rest. These are largely multifactorial in etiology (an admixture of genetic and environmental). Additional factors include infections (e.g., cytomegalovirus), autoimmune disorders (e.g., lupus), endocrine abnormalities (e.g., failure of the corpus luteum), and genital tract abnormalities (e.g., subseptate uterus). The cause of a significant number of early abortions remains unknown. LATE ABORTION Worldwide, the major causes of abortion during the second trimester are infections (e.g., syphilis, malaria), circumvallate placenta, maternal metabolic imbalances (e.g., diabetes mellitus, severe hy- pothyroidism), maternal physiologic impairment (e.g., cardiac disorders, hypertension), maternal dietary insufficiency (e.g., bulimia, avitaminosis B or C), isoimmunizations, exposure to fetotoxic factors (e.g., lead poisoning, substance abuse), trauma (e.g., direct or indirect abdominal injury), and uterine or cervical defects (e.g., cervical incompetency). A wide variety of other etiologies may induce abortion, including severe electric shock, although there is no con- vincing evidence that abortion may be induced by psychic stimuli (e.g., severe fright, grief, anger, or anxiety). DIAGNOSIS OF ABORTION CLINICAL Obtain a complete history and perform a general physical (including pelvic) examination on every patient to determine if special laboratory or other studies are necessary to detect diseases or deficiency states. Classically, the symptoms of abortion are uterine cramping (with or without suprapubic pain) and vaginal bleeding in the presence of previable pregnancy. The integration of the physical examination with these symptoms allows a tentative diagnosis. LABORATORY STUDIES In many cases, a serum pregnancy test is useful. Minimal laboratory studies should include culture and sensitivity of cervical mu- cus or blood (to identify pathogens in infection) and a complete blood count. In some cases, determination of progesterone levels may be useful to detect corpus luteum failure. When hemorrhage is present, blood typing and crossmatching as well as a coagulation panel are necessary. Genetic analysis of aborted material may determine chromosomal abnormality as the etiology. This often provides invaluable in- formation for counseling. DIAGNOSIS OF FETAL DEATH The immunoassay (IA) and radioimmunoassay (RIA) pregnancy tests identify hormones produced by the trophoblast. A steep rise of hCG is the hallmark of normal pregnancies in the peri-implantation interval. Abnormal pregnancies may have a deficiency in hCG levels as well as the rate of increase. Finally, in some abnormal pregnancies, hCG has a lower biologic activity. However, even with death of the embryo or early fetus, groups of trophoblastic cells may remain attached and temporarily viable. Therefore, these pregnancy tests can remain positive for a time. In any event, when a negative RIA test is reported, the pregnancy is over, although gestational debris may be retained. CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 299 BENSON & PERNOLL’S 300 HANDBOOK OF OBSTETRICS AND GYNECOLOGY With a clinical diagnosis of inevitable abortion, ultrasonography is less useful than it is in threatened abortion, when ultrasonography may distinguish a living from a nonliving gestation. Us- ing real-time ultrasonography, the absence of gross motion and especially heartbeat is indicative of fetal death. In some cases, absence of a fetus or fetal disorganization also can be detected. Rarely, gas in the great vessels will be observed. If cardiac motion is present, as is normally noted Ͻ8 gestational weeks (mean sac diameter 2.5 cm), the prognosis is more favorable. DIFFERENTIAL DIAGNOSIS Ectopic gestation is differentiated from spontaneous abortion by the additional symptoms and signs of unilateral pelvic pain or tender adnexal mass. Membranous dysmenorrhea may closely mimic spontaneous abortion, but decidua and villi are absent in the endometrial cast and pregnancy tests (even RIA) are negative. Hyperestrogenism can lead to marked proliferative endometrium with symptoms of cramping and bleeding. Hydatidiform mole usually ends in abortion (Ͻ5 months) but is marked by a very high hCG titer and fetal absence. Pedunculated leiomyoma or cervical neoplasia may also be confused with spontaneous abortion. COMPLICATIONS Hemorrhage and infection are major causes of maternal mortality or morbidity. Although very rare, about three fourths of cases of choriocarcinoma follow abortion. Infertility may result from inflamma- tory tubal occlusion after infected abortion. Rh sensitization may be avoided by administration of Rh immune globulin (see p. 321). The immediate period of pregnancy loss is often accompanied by grief, dysphoria, and anxiety. Longer term grief is characterized by perceived stress and high levels of depressive symptoms (including self-blame). The latter phase lasts for at least a year. Those at risk of developing more intense or longer lasting distress include: those highly desirous of pregnancy, those waiting a long time to conceive, those with no living children, those who had elective abortions or prior losses, those with few warning signs of loss, late pregnancy losses, and younger women with multiple miscarriages. Lit- tle social support, marital and/or family problems, and a history of coping poorly further increase the emotional sequelae of spontaneous abortion. In addition to depression, the more severe distress may be characterized by anxiety disorders, guilt, and concerns about future reproduction. Following spontaneous abortion, a high percentage of patients indicate anger and dissatisfaction with medical care, primarily re- lating to physician insensitivity and lack of opportunity to discuss personal significance of the loss. These responses may be mitigated by: a more caring demeanor at the time; a follow-up appointment soon after the loss; answering why the abortion occurred, and whether it may happen again; and allowing adequate focus on the patient’s feelings. PREVENTION Some abortions can be prevented by treatment of maternal defi- ciencies or disorders before or during pregnancy (e.g., diabetes mellitus, hypertension). Closure of an incompetent cervix may prevent certain abortion. CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 301 FIGURE 10-2. Cerclage of the cervix (Shirodkar) with incompetent os in pregnant patient. BENSON & PERNOLL’S 302 HANDBOOK OF OBSTETRICS AND GYNECOLOGY The usual technique for correction of cervical incompetency, cervical cerclage, involves placement of a suture or a nonabsorbable Mersilene or comparable strand, ribbon, or band beneath the mu- cosa and pericervical fascia at the cervicouterine junction. It may be done during the pregnant state for correction of cervical incom- petence (Fig. 10-2) or accomplished between pregnancies. The physician must then decide whether to release the ligature during labor for vaginal delivery or to perform cesarean section near term. TREATMENT Rapid assessment of the patient’s hemodynamic status should be performed (e.g., blood pressure, pulse rate). A rare critical case will require hemodynamic monitoring. In all except those with minimal bleeding (e.g., a stable complete abortion or an early threatened abortion), establishing an intravenous line is necessary. Administer anti- shock therapy, including fluid and blood replacement when indicated. COMPLETE ABORTION In nearly two-thirds of all patients observation (at least 1 h) for further bleeding may be sufficient. Criteria for these expectantly managed patients include: being afebrile, stable blood pressure, normal heart rate, minimal bleeding, minimal pain, and a hemogram not indicative of infection or anemia. Transvaginal sonography may assist in determining that minimal products of conception are present. Less than 20% of women have hemorrhages. If the products of conception are available, they should be studied for completeness and may be submitted for genetic analysis or other pathologic assessment. In questionable cases, ultrasonic uterine scanning may detail remaining products of conception. After observation, the patient suffering complete abortion may return home with instructions to note signs of infection (fever, chills, or pain), which occurs in 0.8%–3.1%, observe for vaginal hemorrhage, and refrain from in- tercourse or douching until reexamined in about 2 weeks to determine lack of cervical closure or other abnormalities. THREATENED ABORTION Place the patient at bedrest after immediate danger from hemorrhage and infection has passed. Clinical judgment dictates whether bedrest may be accomplished at home (generally only in a nontroubling situation) or in the hospital. Coitus and douches are contraindicated. Ultrasonic scanning is useful to determine fetal well-being. Ob- viously, a major determinant of prognosis is the recognition of fetal life and normality of fetal structures. Abortions without signs of fetal life should be managed as inevitable or incomplete abortions after appropriate discussion with the patient and family. Progesterone therapy has theoretical value in Ͻ5% of abortions (those due to documented deficiency). In such cases, one may administer progesterone parenterally or by vaginal suppository. How- ever, progesterone treatment remains controversial. The main points of contention include proper case selection, questionable efficacy, the potential to continue the retention of an abnormal pregnancy (i.e., missed abortion), and possible teratogenesis. Other therapy (e.g., tocolytics) is even more questionable. In case of questionable fetal viability, the prognosis is best when bleeding and cramping quickly subside, with evidence of cervical closure. The longer the symptoms persist, the more ominous the situation. The prognosis for the patient is good if all products of conception are evacuated or removed and if hydatidiform mole and choriocarcinoma can be ruled out. Correction of maternal disorders may make future successful pregnancies possible. If an aborted fetus is found to have an abnormal karyotype, however, it may be desirable for the parents to obtain a genetic workup. In such cases, genetic investigation in- volving chorionic villus sampling or amniocentesis may be prudent during the next pregnancy. In certain severe transmissible genetic disorders, a determination of the exact defect in one or both parents will assist them and the practitioner to select artificial insem- ination (AID), in vitro fertilization of donor egg or in vitro fertilization with donor egg and donor sperm, adoption, or sterilization. INEVITABLE AND INCOMPLETE ABORTION Once the patient’s hemodynamic status has been assessed and treatment started, retained tissue must be removed or bleeding will continue. Oxytocics (e.g., oxytocin 10 IU/500 mL of 5% dextrose in Ringer’s lactate solution IV at ϳ125 mL/h) should contract the uterus, limit blood loss, aid in the expulsion of clots or tissue, and decrease the possibility of uterine perforation during dilatation and curettage. Ergonovine should be given only after the diagnosis of complete abortion is certain. In some cases, tissue at the external os may simply be removed with sponge forceps. In others, it will be necessary to perform a CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 303 BENSON & PERNOLL’S 304 HANDBOOK OF OBSTETRICS AND GYNECOLOGY suction D & C. Although it is rarely required, a sharp curettage may be lightly performed after the suction D & C to ascertain completeness. A heavy or extensive sharp curettage is potentially haz- ardous because it may lead to uterine synechia. The removal of products of conception usually may be performed safely under paracervical block in an outpatient facility. However, a limiting factor is the ability to adequately observe the patient after the procedure. In cases of heavy bleeding or if the abortion has occurred in the second trimester, hospitalization is usually necessary. The majority of patients receiving outpatient care may be re- leased after observation (1–6 h) confirms the return of physiologic function and absence of early complications. Discharge instructions for the uncomplicated case are as noted for complete abortion. The major complication of D & C is uterine perforation. If this is suspected, the patient must be observed in the hospital for signs of intraperitoneal bleeding, rupture of the bowel or bladder, or peritonitis. Exploratory laparotomy and broad-spectrum antibiotic therapy may be necessary. OTHER ABORTION PROBLEMS MISSED ABORTION Ultrasonic scanning is usually definitive in the diagnosis of fetal death. It also assists in the differential diagnosis of a normal pregnancy with inaccurate dates, pelvic tumor, or the loss of a multiple gestation. Current treatment of missed abortion is induction of labor us- ing prostaglandin E 2 suppositories, enhanced if necessary with di- lute IV oxytocin. The major risk of missed abortion is the possibility of hypofib- rinogenemia. Thus, if the products of conception are contained longer than 4 weeks after fetal death, close monitoring of the serum fibrinogen is mandatory. INFECTED OR SEPTIC ABORTION With infected abortion, expect pelvic and abdominal pain and fever (100–105ЊF). On physical examination, there is often suprapubic tenderness and signs of peritonitis. The pelvic examination will likely, but may not necessarily, reveal a malodorous cervical dis- [...]... globulins are not available for the other blood group isoimmune hemolytic disorders ● ● ● Abortion Approximately 2% of spontaneous abortions and 4%–5% of induced abortions will undergo isoimmunization Spontaneous early first trimester abortions may be treated adequately with 50 m g RhIgG, However, later abortions and induced abortions require the usual dose (300 m g) Amniocentesis There is an 11% chance of... or IM iron therapy or both to replenish iron stores PROGNOSIS Ectopic pregnancy is a life-threatening disorder in Ͼ10% of cases, and Ͼ1% of these patients die of internal hemorrhage and shock or CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 319 of later complications Survival of the fetus in extrauterine pregnancy is exceptional Ectopic pregnancy (and probably its antecedents) severely limit future reproductive... intrauterine pregnancy and fewer repeat ectopic gestations with medical therapy Ectopic pregnancy recurs in about 15% of cases In combined extrauterine and intrauterine pregnancy, one or the other usually is diagnosed—rarely both Generally, the extrauterine pregnancy succumbs, and 60% of the intrauterine pregnancies go on to viability COMPLICATIONS Without surgical intervention, a ruptured ectopic pregnancy. .. damaged tubes or other organs If the pregnancy is early or if tubal missed abortion has occurred, perform salpingostomy to enucleate the pregnancy and preserve the tube Ligate bleeding points Suture closure is not necessary Indications for organ removal include: Uncontrollable hemorrhage Severely damaged tube (requires cornual excision—not resection—to prevent repeat ectopic pregnancy and endosalpingosis... required in ruptured interstitial or cervical pregnancy Oophorectomy is necessary in ovarian pregnancy but is not recommended in cases where tubal removal is required Laparoscopy has been used as the standard by which other therapy is measured However, surgical treatment is very dependent on the experience and expertise of the surgeon, the equipment CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 317 and the facilities... CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 309 FIGURE 10-3 Sites of ectopic pregnancies Uterine ectopic gestations (rare) may occur with implantation in the cornua, a uterine diverticulum, uterine sacculation, rudimentary horn, or the muscular wall (intramural) Combined intrauterine pregnancy (heterotopic) This occurs in 1/17,000–30,000 pregnancies Other rare possibilities include intraligamentous Pregnancy. .. interstitial pregnancy does blood from the tube drain via the uterus into the vagina Lower abdominal, pelvic, or low back pain may be secondary to tubal distention or rupture Isthmic pregnancy usually ruptures in about 6 weeks, and hemorrhage due to ampullary pregnancy occurs at 8–12 weeks Cornual pregnancies are most commonly carried to the second trimester before rupture Intraabdominal pregnancy may... antepartum, 7% within 6 months of delivery, and 7% early in the subsequent pregnancy ABO incompatibility affords some protection from isoimmunization, but not enough for reliance It is imperative that every pregnant woman be screened for her Rh status because with the administration of immune globulin (RhIgG), kernicterus can be virtually eliminated CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 321 DIAGNOSIS ● ●... ectopic pregnancy is nearly universal CLASSIFICATIONS Ectopic pregnancy is classified according to the site of implantation (the following is in decreasing order of occurrence) Tubal (98–99%) ectopic pregnancies are further subdivided into the anatomic section involved: ampullary (55%), isthmic (25%), fimbrial (17%), interstitial (angular, cornual) (2%), and bilateral (very rare) (Fig 10-3) Ovarian pregnancy. .. prophylaxis does not alter the delivery plan If the pregnancy goes beyond 40 weeks, however, it may be prudent to administer antepartum prophylactic RhIgG again Antepartum hemorrhage Patients with placenta previa or abruptio placenta who do not deliver immediately should CHAPTER 10 EARLY PREGNANCY COMPLICATIONS ● ● ● ● 323 receive 300 m g of RhIgG If the pregnancy is carried 12 weeks from the time of the . 10-1). CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 297 FIGURE 10-1. Top. Complete abortion. At right, product of complete abortion. Bottom. Incomplete abortion. At right, product of incomplete abortion. BENSON. or more nonviable pregnancies. Induced abortion is the purposeful interruption of pregnancy by medical or surgical techniques. ETIOLOGY OF SPONTANEOUS ABORTION EARLY ABORTION Abnormal products of conception. as common). ECTOPIC PREGNANCY A fertilized ovum implanted outside the uterine cavity is an ectopic pregnancy. Ectopic pregnancy usually results from conditions that CHAPTER 10 EARLY PREGNANCY COMPLICATIONS 307 BENSON