Dystocia

Dr.A Danesh MD

After an ectopic pregnancy, there is a 7- to 13-fold increase in the risk of a subsequent ectopic pregnancy. The chance that asubsequent pregnancy will be intrauterine is 50% to 80%, and the chance thatthe pregnancy will be tubal is 10% to 25%; the remaining patients will be infertile

Chlamydia is an important pathogen causing tubal damage and bsequenttubal pregnancy. Because many cases of chlamydia salpingitis are indolent, cases maynot be recognized or, if recognized, may be treated on an outpatient basis. Chlamydia

has been cultured from 7% to 30% of patients with tubal pregnancy

Women who conceive with an IUD in place, however, are 0.4 to 0.8 timesmore likely to have a tubal pregnancy than those not using contraceptives. BecauseIUDs prevent implantation more effectively in the uterus than in the tube, awoman conceiving with an IUD is 6 to 10 times more likely to have a tubal pregnancythan if she conceives without using contraception

Duration of IUD use does not increase the absolute risk for tubal pregnancy (1.2 per

1,000 years of exposure), but with increasing use, there is an increase in the

percentage of pregnancies that are tubal

Progesterone-only contraceptives, includingoral contraceptives (minipill) and subdermal

implants (Norplant), protect against bothintrauterine and ectopic pregnancy when compared

with no contraceptive use. If a pregnancydoes occur, however, the chance of the pregnancy

being ectopic is 4% to 10% for theminipill (34,35) and up to 30% if pregnancy occurs

while implants are in place

Past use of oral contraceptives does not increase

the subsequent risk for ectopic pregnancy

Condom and diaphragm use protects against both intrauterine and ectopic pregnancy, and there

is no increased incidence of ectopic pregnancy

The greatest risk of pregnancy, including ectopic pregnancy, occurs in the first 2

years after sterilization

The risk of tubal pregnancy after any sterilization procedure is 5% to 16% )

Although it is clear that tubal surgeryis associated with an increased risk for

ectopic pregnancy, it is unclear whetherthe increased risk results from the

surgical procedure or from the underlying problem

After either tubal removal or conservation, the rates for intrauterine pregnancy (40%)

and ectopic pregnancy (12%) have been found to be identical

ovarian cystectomy or wedge resection increases therisk for ectopic pregnancy, presumably because of peritubal scarring

There is no established association between ectopic pregnancy and spontaneous abortion

Although the incidence of ectopic pregnancy increases with age and parity, there also is a significant increase in nulliparous women undergoing infertility

treatment )

Hormonal alterations characteristic of clomiphene citrate and gonadotropin

ovulation-induction cycles may predispose tubal implantation. About 1.1% to 4.6%

of conceptions associated with ovulation induction are ectopic pregnancies

Salpingitis isthmica nodosa (SIN) is a noninflammatory pathologic condition of the tube

in which tubal epithelium extends into the myosalpinx and forms a true diverticulum.

.This condition is found moreoften in the tubes of women with an

ectopic pregnancy than in nonpregnantwomen )

Endometriosis or leiomyomas can cause tubal obstruction

In DES-exposed women, the risk for ectopic pregnancy was 13% in

those who had uterine abnormalities compared with 4% in those who had a normal uterus.

No specific type of defect was related to the risk for ectopic pregnancy.

Current cigarette smoking is associated with a more than twofold increased risk

for tubal pregnancy )

Chorionic villi, usually found in the lumen, are pathognomic findings of tubal

pregnancy. Gross or microscopic evidence of an embryo is seen in two thirds of cases

Hemoperitoneum is nearly always present but is confined to the cul-de-sac

unless tubal rupture has occurred. The natural progression of tubal pregnancy is

either expulsion from the fimbriated end (tubal abortion), involution of the conceptus,

or rupture, usually around the eighth gestational week.

The Arias-Sella reaction is a nonspecific finding that can

be seen in patients with intrauterine pregnancies

Figure 18.2 The Arias-Stella reaction of the endometrium. The glands are closely

packed andhypersecretory with large, hyperchromatic

nuclei suggesting malignancy

The classic symptom triad of ectopic pregnancy is pain, amenorrhea, and vaginal

bleeding. This symptom group is present in only about 50% of patients, however, and

is most typical in patients in whom an ectopic pregnancy has ruptured. Abdominal

P.610pain is the most common presenting symptom,

but the severity and nature of thepain vary widely. There is no pathognomonic

pain that is diagnostic of ectopicpregnancy

An adnexal mass maybe palpable in up to 50% of cases, but the

mass varies markedly in size, consistency,

and tenderness. A palpable mass may be the corpus luteum and not the

ectopic pregnancy

Quantitative β-hCG measurements are the diagnostic cornerstone for ectopic

pregnancy. The hCG enzyme immunoassay, with a sensitivity of 25 mIU/mL, is an accurate screening test for detection of ectopic pregnancy. The assay is positive in virtually all documented ectopic pregnancies.

as phantom hCG, in which the presence of heterophile antibodies or proteolytic

enzymes causes a false-positive hCG result. Because the antibodies are large

glycoproteins, significant quantities of the antibody are not excreted in the urine. Thus, in

the patient with hCG levels less than 1,000 mIU/mL, a urine pregnancy test should

be performed and confirmatory positive results obtained before instituting

treatment

The hCG doubling time can help to differentiate an ectopic pregnancy from an

intrauterine pregnancy—a 66% rise in the hCG level over 48 hours (85% confidence

level) represents the lower limit of normal values for viable intrauterine pregnancies

)82 .(About 15% of patients with viable intrauterine pregnancies have less than a

66% rise in hCG level over 48 hours, and a similar percentage with an ectopic

pregnancy have more than a 66% rise

The hCG pattern that ismost predictive of an ectopic pregnancy is one

that has reached a plateau (adoubling time of more than 7 days). For falling

levels, a half-life of less than 1.4 daysis rarely associated with an ectopic pregnancy,

whereas a half-life of more than 7 daysis most predictive of ectopic pregnancy.

Serial hCG levels are usually required when the results of the initial

ultrasonography examination are indeterminate (i.e., when there is no evidence of

an intrauterine gestation or extrauterine cardiac activity consistent with an

ectopic pregnancy). When the hCG level is less than 2,000, doubling time helps to

predict viable intrauterine gestation (normal rise) versus nonviability (subnormal

rise). With normally rising levels, a second ultrasonography examination is

performed when the level is expected (by extrapolation) to reach 2,000 mIU/

mL. Abnormally rising levels (less than 2,000 mIU/mL and less than 50% rise over

48 hours) indicate a nonviable pregnancy

If the hCG level is more than 300 mIU/mL on day 16 to 18 after artificial insemination, there is an 88% chance of a live birth (84). If the hCG level is less than 300 mIU/mL, the chance of a live birth is only 22%

serum progesterone levels higher than 25ng/mL, whereas only 1.5% of patients with

ectopic pregnancies have serum progesterone levels higher than 25 ng/mL, and most of these pregnancies exhibit cardiac activity

A serum progesterone level of less than 5 ng/mL is highly suggestive of an abnormal pregnancy, but it is not 100% predictive. The risk of a normal pregnancy with a

serum progesterone level of less than 5 ng/mL is about 1 in 1,500

Estradiolcreatine kinaseSchwangerschafts protein 1 (SP1), C (PAPP-C) or pregnancy-

specific β glycoprotein (PSBS), RelaxinCA125(AFP) C-reactive protein

C-reactive protein

The earliest ultrasonographic finding of an intrauterine pregnancy is a small fluid

space and the gestational sac, surrounded by a thick echogenic ring, located

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Ovid: Berek & Novak's Gynecologyeccentrically within the endometrial cavity. The earliest normal

gestational sac is seenat 5 weeks of gestation with transabdominal ultrasonography and

at 4 weeks ofgestation with transvaginal ultrasonography (112). As the

gestational sac grows, ayolk sac is seen within it, followed by an embryo with cardiac

activity.

Morphologically, identification of the double decidual sac sign (DDSS) is the best

method of ultrasonographically differentiating true sacs from pseudosacs

The appearance of a yolk sac within the gestational sac is superior to the DDSS

in confirming intrauterine pregnancy

The presence of an adnexal gestational sac with a fetal pole and cardiac activity is

the most specific but least sensitive sign of ectopic pregnancy, occurring in only

10%to 17% of cases

Complex or solid adnexal masses are frequently associated with ectopic

pregnancy (1,3,19); however, the mass may represent a corpus luteum,

endometrioma, hydrosalpinx, ovarian neoplasm (e.g., dermoid cyst), or

pedunculated fibroid

Accurate interpretation of ultrasonography findings requires correlation with thehCG level (discriminatory zone) (114,119,122,124). All viable intrauterine

pregnanciescan be visualized by transabdominal ultrasonography for serum hCG levels higher

than 6,500 mIU/mL; none can be seen at 6,000 mIU/mL. The inability to detectan intrauterine gestation with serum hCG levels higher than 6,500 mIU/mL indicates

the presence of an abnormal (failed intrauterine or ectopic) pregnancy. Intrauterinesacs seen at hCG levels below the discriminatory zone are abnormal and represent

either failed intrauterine pregnancies or the pseudogestational sacs of ectopicpregnancy. If there is no definite sign of an intrauterine gestation (the empty uterus

sign) and the hCG level is below the discriminatory zone, the differentialdiagnosis includes the following considerations:

Normal intrauterine pregnancy too early for visualization

Abnormal intrauterine gestationRecent abortion

Ectopic pregnancyNonpregnant patient

Discriminatory zones for transvaginal ultrasonography have

been reported at levels from 1,000 to 2,000 mIU/mL (114,119,122,124). Discriminatory

zones vary according to the expertise of the examiner and capability of the equipment.

Although the discriminatory zone for intrauterine pregnancy is well established, there

is no such zone for ectopic pregnancy.

high-velocity, low-resistance signal is localized to the area of developing placentation This pattern, seen near the endometrium, is associated with normal

and abnormal intrauterine pregnancies and is termed peritrophoblastic flow .

Uterine curettage is performed when the pregnancy has been confirmed to be

nonviable and the location of the pregnancy cannot be determined by

ultrasonography .

Laparoscopy is the gold standard for the diagnosis of ectopic pregnancy.

An algorithm for the diagnosis of ectopic pregnancy without laparoscopy

proved to be 100% accurate in a randomized clinical trial

Suction curettage is used to differentiate nonviable intrauterine pregnancies from

ectopic gestations (less than 50% rise in hCG level over 48 hours, an hCG level of

less than 2,000 mIU/mL, and indeterminate ultrasonography findings). Performance

of this procedure avoids unnecessary use of methotrexate in patients with

abnormal intrauterine pregnancy that can be diagnosed only by evacuating the uterus .

An unlikely potential problem with suction curettage is missing either an early

nonviable intrauterine pregnancy or combined intrauterine and extrauterine pregnancies.

Linear salpingostomy is currently the procedure of choice when the patient has

an unruptured ectopic pregnancy and wishes to retain her potential for future fertility.

The products of conception are removed through an incision made into the tube on

Laparotomy is indicated when the patient becomes

hemodynamically unstable, whereas laparoscopy

is reserved for patients who are hemodynamically stable. A ruptured ectopic pregnancy does not necessarily require laparotomy .

Pregnancy rates are similar in patients treated by either laparoscopy or laparotomy. Tubal patency on the ipsilateral side

after conservative laparoscopic management is about 84%.

In a study of 143 patients followed after undergoing laparoscopic procedures for

ectopic pregnancy, the overall intrauterine pregnancy rates for laparoscopic salpingostomy (60%) and laparoscopic

salpingectomy (54%) were not significantly different

Commonly reported side effects include leukopenia, thrombocytopenia, bone marrow

aplasia, ulcerative stomatitis, diarrhea ,and hemorrhagic enteritis. Other reported side

effects include alopecia, dermatitis, elevated liver enzyme levels, and pneumonitis (146).

However, no significant side effects have been reported at the low doses used for ectopic

pregnancy treatment. Minor side effects have been reported with multiple doses;

Single-dose Methotrexate Protocol for Ectopic Pregnancya

DayTherapy

0 D & C, hCG1 CBC, SGOT, BUN, creatinine, blood type and Rh

24

Methotrexate 50 mg/m IM

7 hCGD & C, dilation and curettage; hCG, human chorionic gonadotropin; CBC, complete blood

count; SGOT, serum glutamic-oxaloacetic transaminase; BUN, blood urea nitrogen; IM ,

intramuscularly.a

If less than a 15% decline in hCG level between days 4 and 7, give second dose of 2

methotrexate, 50 mg/m ,on day 7 .

If more than a 15% decline in hCG level between days 4 and 7, follow weekly until hCG is below 10 mIU/mL .

In patients not requiring D & C (hCG > 2,000 mIU/mL and no gestational sac on transvaginal ultrasonography), days 0 and 1 are combined.

Physician Checklist Obtain hCG level.

Perform transvaginal ultrasound within 48 hours. Perform endometrial curettage if hCG level is less than 2,000 mIU/mL.

Obtain normal liver function (SGOT), normal renal function (BUN, creatinine), and a normal CBC (WBC < 2,000/mL and platelet count > 100,000)

Administer RhoGAM if patient is Rh-negative. Identify unruptured ectopic pregnancy smaller than 3.5 cm.

Obtain informed consent. Prescribe FeSO

325 mg PO bid if hematocrit is less than 30%.4

Schedule follow-up appointment on days 4, 6, and 7.Patient Instructions

Refrain from alcohol use, multivitamins containing folic acid, and sexual intercourse until hCG level is negative.

Call your physician if: You experience prolonged or heavy vaginal bleeding.

The pain is prolonged or severe (lower abdomen and pelvic pain is normal during the first 10 14 days of treatment.(

You use oral contraception or barrier contraceptive methods.About 4% 5% of women experience unsuccessful methotrexate treatment and require

surgery .hCG, human chorionic gonadotropin; SGOT, serum glutamic-oxaloacetic transaminase ;

BUN, blood urea nitrogen; CBC, complete blood count; WBC, white blood cell; PO, by mouth; bid, twice daily.

After intramuscular administration of methotrexate, patients are monitored on

an outpatient basis. Patients who report severe pain or pain that is prolonged

are evaluated by measuring hematocrit levels and performing

transvaginal ultrasonography .

To maximize the safety of treatment and to eliminate the possibility of treating in

the presence of a nonviable or early viable intrauterine pregnancy, patients

considered candidates for methotrexate treatment should include those to whom

the following factors apply:

An hCG level is present after salpingostomy or salpingotomy.

?The hCG level is rising or reached a plateau at least

12 to 24 hours after suction curettage. ?

No intrauterine gestational sac or fluid collection is detected by transvaginal ultrasonography ,

the hCG level is greater than 2,000 mIU/mL, the hCG level is rising, and an ectopic pregnancy

mass of 4.0 cm or less without cardiac activity or 3.5 cm or less with cardiac activity is visualized.

Ultrasonography findings should be interpreted with caution because most

unruptured ectopic pregnancies will be accompanied by fluid in the cul-de-sac.

When using the single-dose intramuscular regimen, the

incidence of side effects is less than 1% ,and the failure rate is comparable to that of

conservative laparoscopic surgery .One problem that remains puzzling is the inability to

predict treatment failures with the use of methotrexate. However, the same is true

with conservative surgical procedures; thus, the need to monitor hCG

levels after salpingostomy or methotrexate remains

Comparison of laparoscopically treated patients with

methotrexate-treated patients suggests that the two methods have similar

reproductive outcomes.

Salpingocentesis is a technique in which agents such as KCl, methotrexate, prostaglandins ,

and hyperosmolar glucose are injected into the ectopic pregnancy transvaginally

using ultrasonographic guidance, transcervical tubal cannulization, or laparoscopy. Agents

injected under ultrasonographic guidance have included methotrexate The

KCl, combined methotrexate and KCl, and prostaglandin E

Some ectopic pregnancies resolve by resorption or by tubal abortion, obviating the

need for medical or surgical therapy

Persistent ectopic pregnancy occurs when a patient has undergone conservative

surgery (e.g., salpingostomy, fimbrial expression) and viable trophoblastic tissue

remains .

A slower decline of serum hCG levels has been seen in patients

treated by salpingostomy compared with patients treated by salpingectomy. The

incidence of persistence after laparoscopic linear salpingostomy ranges from 3% to

20%

Persistent ectopic pregnancy can be treated surgically or medically; surgical

therapy consists of either repeat salpingostomy or, more commonly ,

salpingectomy. Methotrexate offers an alternative to patients who are

hemodynamically stable at the time of diagnosis. Methotrexate may be the treatment

of choice because the persistent trophoblastic tissue may not be confined to the tube

and, therefore, not readily identifiable during repeat surgical exploration (191,192,193).

Chronic ectopic pregnancy is a condition in which the pregnancy does not

completely resorb during expectant management

The incidence of cervical pregnancy in the United States ranges from 1 in 2,400 to 1

in 50,000 pregnancies

Ultrasound Criteria for Cervical Pregnancy1 .Echo-free uterine cavity or the presence of a false

gestational sac only2 .Decidual transformation of the endometrium with

dense echo structure3 .Diffuse uterine wall structure

4 .Hourglass uterine shape5 .Ballooned cervical canal

6 .Gestational sac in the endocervix7 .Placental tissue in the cervical canal

8 .Closed internal os

When a cervical pregnancy is diagnosed before surgery, the preoperative

preparation should include blood typing and cross-matching, establishment of

intravenous access, and detailed informed consent. This consent should include

the possibility of hemorrhage that may require transfusion or hysterectomy .

Various techniques that can be used to control bleeding include uterine packing, lateral cervical suture

placement to ligate the lateral cervical vessels, placement of a cerclage, and insertion of

an intracervical 30-mL Foley catheter in an attempt to tamponade the bleeding.

Alternatively ,angiographic artery embolization can be used. If laparotomy is

required, an attempt can be made to ligate the uterine or internal iliac arteries

(202,203,204). When none of these methods is successful, hysterectomy is required.

A pregnancy confined to the ovary represents 0.5% to 1% of all ectopic pregnancies

/and is the most common type of nontubal ectopic pregnancy

Table 18.6 Criteria for Ovarian Pregnancy Diagnosis1 .The fallopian tube on the affected side must be

intact.2 .The fetal sac must occupy the position of the

ovary.3 .The ovary must be connected to the uterus by the

ovarian ligament.4 .Ovarian tissue must be located in the sac wall.

ovarian cystectomy has become the preferred treatment

Abdominal pregnancy is associated with high morbidity and

mortality, with the risk for death 7 to 8 times greater than from tubal ectopic

pregnancy and 90 times greater than from intrauterine pregnancy.

Diagnosis of Primary Abdominal Pregnancy

1 .Presence of normal tubes and ovaries with no evidence of recent or past pregnancy

2 .No evidence of uteroplacental fistula3 .The presence of a pregnancy related

exclusively to the peritoneal surface and early

enough to eliminate the possibility of secondary implantation after primary tubal

nidation

surgical intervention is recommended when an

abdominal pregnancy is diagnosed.

Interstitial pregnancies represent about 1% of ectopic pregnancies

Interligamentous pregnancy is a rare form of ectopic pregnancy that occurs in about 1

in every 300 ectopic pregnancies

Heterotropic pregnancy occurs when intrauterine and ectopic pregnancies coexist .

The reported incidence varies widely from 1 in 100 to 1 in 30,000 pregnancies

Twin or multiple ectopic gestations occur less frequently than heterotropic gestations

and may appear in a variety of locations and combinations .

Complex or solid adnexal masses are frequently associated with ectopic

pregnancy (1,3,19); however, the mass may represent a corpus luteum,

endometrioma, hydrosalpinx, ovarian neoplasm (e.g., dermoid cyst), or

pedunculated fibroid

DYSTOCIA

uterine contractility

maternal pelvimetry

position and size of the fetus

Primary Dysfunctional Labor

Inadequate uterine contractility to maintain appropriate progress in labor

Four concerted synchronous contractions every 10 minutes (Gap junctions)

uterine embryologic abnormalities such as a didelphic uterus or bicornuate uterus

Cephalopelvic Disproportion

Fetal birth weight

Fetal head

Maternal pelvic inlet

                                                                             

.

Abnormal Position of the Fetal Head

0ccipital posterior (OP)

Deep transverse arrest

Deflexion abnormalities such as face and brow presentations

Asynclitism

The sagittal suture of the head is either deviated posteriorly or anteriorly in relation to the maternal outlet

Second stage of labor is often prolonged and arrest of descent

Fetal Abnormalities

Fetuses with neuromuscular disease ,

Utero demise

hydrocephalus

hydrops fetalis

tumors of the head or sacrum can lead to mechanical obstruction

Lie of fetous

Breech

Trasvers

oblique

Prolonged Latent Phase

In nulliparous women uterine activity without cervical change for more than 20 hours

Multiparas this time period is 14 hours

Arrest of Dilation

occurs when there is no cervical change after 2 hours in the active phase of labor despite uterine activity

Arrest of Descent

If the patient does not gain station of 1 cm after an hour of adequate pushing efforts, an arrest of descent is diagnosed

Precipitate labor disorders

Precipitate labor

Delivery in less than 3 hours from onset of contraction

Precipitate dilatation 5cm or more per hour in primipara or10cm 0r more per hour in multipara

Protracted Active Phase

In nulliparous patients, cervical change is less than 1.2 cm per hour

In multiparous patients cervical change is occurring at less than 1.5 cm per hour .

Prolonged Second Stage

prolonged second stage is diagnosed when the fetal head descends less than 1 cm per hour.

A second stage lasting longer than 2 hours has traditionally been considered abnormal

longer than 2 hours in nulliparas or 1 hour in multiparas or 3 and3 hour for conduction anesthesia