Ectopic pregnancy is a pregnancy which implants outside the endometrial cavity. These pregnancies will ultimately result in the death of the fetus. An ectopic pregnancy is an abnormal pregnancy which, without timely diagnosis and treatment, can become a life-threatening situation. 2% of all US pregnancies are ectopic and 98% of ectopics are tubal in location. Despite improved diagnostic methods leading to earlier detection and treatment, hemorrhage from rupture of tubal ectopic pregnancy is still the leading cause of pregnancy related maternal death in the first trimester and accounts for 10-15% of all pregnancy related deaths.
Risk factors for Ectopic pregnancy:
Previous ectopic pregnancy
Prior tubal surgery (9x increased risk)
Pelvic inflammatory disease (6x increased risk)
Infertility > 2 yrs
Pelvic or abdominal surgery
Sexually transmitted diseases
Age >35 (3x increased risk)
Current use of IUD
** 50% of women with ectopic have one or more risk factors **
When to suspect an ectopic pregnancy:
The classic teaching included the clinical triad of abdominal pain, amenorrhea, and vaginal bleeding. Unfortunately, only about 50% of patients present with all 3 symptoms.
Step 1: Am I pregnant ?
Urine pregnancy test Positive ? Yes or No
ICON→99.4% sensitive for pregnancy. The urine pregnancy test is very sensitive and can detect pregnancy before 1st missed menstrual period. In very early pregnancy, a very dilute urine, high levels of vitamin C, expired tests – may decrease the sensitivity of the test.
Step 2: Physical Exam
Review vital signs for hemodynamic stability. Abdominal exam: Peritoneal signs ? Pelvic exam: Os, uterine size, cervical motion tenderness, adnexal findings ?
** No combination of H&P elements can reliably exclude ectopic. **
Step 3: Do I need labs ?
Quant β-HCG – helps now and in follow-up
Type and Rh – If Rh Neg-, Rhogam to prevent isoimmunization
UA, C&S – even if asymptomatic
The discriminatory zone (DM) of β-HCG is the level above which a transvaginal ultrasound should reliably visualize a gestational sac within the uterus in a normal intrauterine pregnancy. The typical DM is 1500 mIU/mL with transvaginal ultrasound. The absence of an intrauterine pregnancy on a scan when the β-HCG level is above the discriminatory zone represents an ectopic pregnancy or a recent abortion.
A serial increase in serum Quantitative β-HCG levels indicates the presence of viable uterine pregnancy. β-hCG doubles every 1.5 days up to 5 weeks after the last menstrual period, and then every 3.5 days from the 7thweek.  It is very important to remember that ectopic pregnancies have an abnormal production of β-HCG. Almost half of ectopics fall below the β-HCG discriminatory zone.
Step 4: Location, location, location….
Use ultrasound to detect an intrauterine pregnancy (IUP).
Simplifying things, the pelvic ultrasound has one of three possible results: positive for ectopic pregnancy, positive for intrauterine pregnancy, and indeterminate. 80% of women with an ectopic pregnancy will have an initial ultrasound that is either normal or nondiagnostic, with nothing showing in the uterus or adnexa.
+ IUP = NORMAL pregnancy
In cases where NO IUP is identified: if Quant β-HCG >1,500 = likely ectopic – GYN consult.
If the Quant β-HCG <1,500 this could be a normal pregnancy or ectopic. If the β-HCG < 1500 and the patient is unstable or has peritoneal signs obtain immediate GYN consult for laparoscopy. If the patient is stable, consider the patient’s ectopic risk factors and admit or discharge for GYN follow-up and repeat HCG and ultrasound in 2 days.
Heterotopic pregnancy (IUP + Ectopic) is very rare. 1:5,000 pregnancies without fertility agents.
First Trimester Pregnancy Ultrasound:
Management of Ectopic Pregnancy:
Ectopic Pregnancy can be managed surgically or medically.
Indications for surgical treatment of ectopic pregnancy include the following:
The patient is not a suitable candidate for medical therapy.
Medical therapy has failed.
The patient has a heterotopic pregnancy with a viable intrauterine pregnancy.
The patient is hemodynamically unstable and needs immediate treatment.
Medical management in ectopic pregnancy is typically performed with Methotrexate. Methotrexate is a chemotherapeutic agent that disrupts cell multiplication. When used in the treatment of ectopic pregnancy, methotrexate is administered in a single or in multiple intramuscular (IM) injections.
Indications for Methotrexate therapy include: Unruptured ectopic mass, β-HCG <5000, hemodynamic stability, good follow-up available→ need to return every 2 days for β-HCG recheck, no hepatic or renal disease, WBC >2000 and Platelets>100,000.
Contraindications for Methotrexate therapy include a β-HCG level of greater than 5,000 IU/L, fetal cardiac activity, and free fluid in the cul-de-sac on ultrasound which may represent a tubal rupture.
Emergency Medicine bedside algorithm in the first trimester pregnant patient with symptoms and presentation concerning for possible ectopic pregnancy: Dr. Eric Snoey, an emergency physician at Alameda County Medical Center, Oakland, Calif., offered a treatment algorithm that relies completely on the history, physical, and ultrasound.
Determine if the symptomatic patient is hemodynamically stable. If she is not stable, go to resuscitation and the FAST (Focused Abdominal Sonography for Trauma) exam. If she is stable, try to determine the location and development of the embryo by using transvaginal or transabdominal ultrasound.
If the patient has a threatened abortion (i.e., intrauterine pregnancy confirmed by ultrasound with pain, possible bleeding, and closed os), discharge her with a recommendation for bed rest and a quick follow-up with the obstetrician, or a quick return to the ED if symptoms worsen.
If no intrauterine pregnancy can be seen, then scan the adnexa. If the scan shows a complex adnexal mass or an unusual amount of free fluid, get an immediate obstetric consult.
With a negative or indeterminate scan, discharge the patient home if vital signs are stable and pain and bleeding are acceptably low. Advise a follow-up β-HCG test within 48 hours.
If the patient is experiencing unacceptable levels of pain and bleeding, then admit her for observation.
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