Ectopic pregnancy (Extrauterine pregnancy, EUP)
Exra-uterine-pregnancy is the implantation of a blastocyst in any location other than the inner lining of the uterus. The large majority (95%) of extrauterine pregnancies occur in the Fallopian tube. However, they can occur in other locations, such as the ovary, cervix, and abdominal cavity.
The rates of EUPs are higher in pregnancies resulting from assisted reproduction techniques (ART) than in spontaneous pregnancies.
Ectopic pregnancy and the frequency distribution for this phenomenon.
Other factors associated with the development of EUP include:
Previous surgery to the fallopian tube
Pelvic lesions that distort the tube
Developmental abnormalities of the tube
Altered tubal motility.
EUP after ART
The incidence of EUPs after IVF ranges from 2.1 to 9.4% of all clinical pregnancies. In 1996, the Society for Assisted Reproductive Technology (SART) reported a decrease in the incidence of EUP to 0.8% of transfers and 1.6% of pregnancies, compared with 0.9% and 2.8%, respectively, in 1995. This finding was attributable to the decrease in the proportion of couples with tubal-factor infertility undergoing IVF treatment and a concomitant increase in couples with male-factor infertility.
Data on risk factors for EUP after IVF are still unclear but suggest the followings:
Prior ectopic pregnancy
Tubal-factor infertilit (3.6% compared with those with normal tubes 1.2%)
A history of PID
Those who received a higher culture-medium volume
Those with a higher progesterone/E2 ratio on the day of ET
Using zygote intrafallopian transfer (ZIFT) technology
Heterotopic pregnancy following ART
The general incidence of combined intrauterine and extrauterine (heterotopic) pregnancy is 1:15000– 30000, and it increases dramatically to 1:100 in pregnancies following ART or ovulation induction. Although a distorted pelvic anatomy is responsible for the predisposition to both extrauterine and heterotopic pregnancy, heterotopic pregnancies are associated with a greater number of embryos transferred, whereas EUP is not. In about 70% of cases, the outcome of the intrauterine pregnancy is favorable (live birth) once the extrauterine pregnancy is terminated. A high index of suspicion and early intervention are mandatory to salvage the viable intrauterine pregnancy and prevent maternal mortality.
Pain is usually the first symptom of an ectopic pregnancy. The pain, often one-sided, may be in the pelvis, abdomen or even in the shoulder or neck (due to blood from a ruptured ectopic pregnancy building up under the diaphragm and the pain being "referred" up to the shoulder or neck). The pain is usually sharp and stabbing. Weakness, dizziness or lightheadedness, and a sense of passing out upon standing can represent serious internal bleeding, requiring immediate medical attention.
• Physical examination is unreliable for clinicians who face this significant diagnostic challenge. Although findings at physical examination may be variable, they may include the following:
• Vaginal bleeding may be mild or absent. Up to 30% of patients with ectopic pregnancies have no vaginal bleeding.
• Abdominal pain may be minimal or severe.
• Shoulder pain is suggestive of peritoneal free fluid (significant hemorrhage).
• Ectopic pregnancies can be accompanied by sloughing material, which is suggestive of a miscarriage.
• Adnexal masses may be palpable in only 60% of patients (under anesthesia).
• Tenesmus or syncope may occur.
• Decidual cast may be passed.
• Clinical shock may occur after rupture.
• No combination of physical findings may reliably exclude the diagnosis of ectopic pregnancy.
Diagnosis and treatment
Noninvasive diagnostic measures using transvaginal ultrasonography combined with serum hCG monitoring have proved to be a reliable tool in the diagnosis of EUP. Since most pregnancies following ART are monitored at an early stage before the onset of symptoms, early diagnosis of the condition and improved management and care have resulted in a decline in the morbidity and mortality of EUP.
Ectopic pregnancy of the right tube as seen through a laparoscop
Pregnancy, ectopic. An endovaginal sonogram reveals an intrauterine pregnancy at approximately 6 weeks. A yolk sac (ys), gestational sac (gs), and fetal pole (fp) are depicted
Ectopic pregnancies cannot continue to birth (term).
Treatment of an ectopic pregnancy varies, depending on how medically stable the woman is and the size and location of the pregnancy.
Robert Lawson Tait, a British surgeon, is credited with performing the first successful laparotomy for ruptured tubal pregnancy in 1883. This was the first successful surgical management of ruptured tubal pregnancy. At a time when ectopic pregnancy was associated with a greater than 60% mortality rate. By the 1920s, laparotomy and ligation of the bleeding vessels with removal of the affected tube was the standard of care and remained so until operative laparoscopy and salpingostomy replaced laparotomy and salpingectomy in the late 1970s.
In the 1980s and 1990s, medical therapy of ectopic pregnancy has been implemented and has replaced surgical treatment in many cases. Thus, in less than 3 decades, treatment has evolved from a surgical emergency to conservative medical management.
Early treatment of an ectopic pregnancy with the antimetabolite methotrexate which acts by inhibiting the metabolism of folic acid. This mode of treatment has proven to be a viable alternative to surgical treatment since 1993. If administered early in the pregnancy, methotrexate can disrupt the growth of the developing embryo.
Bilateral tubal pregnancies with interauterine pregnancy following the transfer of 3 embryos