Can a blood test detect an ectopic pregnancy?

A blood test is a test that many people now have to do during a physical examination or a body check. This test can detect whether there are any problems in a person's blood, as well as any problems in various aspects of the body. Therefore, a blood test is very important. Some people also think that a blood test can detect some potential hidden dangers in the body. Can a blood test detect an ectopic pregnancy?

Disease diagnosis

diagnosis

Before tubal pregnancy occurs, miscarriage or rupture, the clinical manifestations are not obvious and diagnosis is difficult. Auxiliary examinations should be combined to make a clear diagnosis as early as possible.

Differential Diagnosis

Tubal pregnancy needs to be differentiated from intrauterine pregnancy, abortion, acute appendicitis, acute salpingitis, corpus luteum rupture and ovarian cyst pedicle torsion.

Common inspection items

Human chorionic gonadotropin, gynecological ultrasound, laparoscopy, digital rectal examination, urine human chorionic gonadotropin (HCG)

Inspection method

1. Urine pregnancy test: simple and quick. A positive result can assist in diagnosis, while a negative result needs to be ruled out by quantification of blood β-HCG.

2. Quantification of blood β-HCG: It is an important method for early diagnosis of ectopic pregnancy. In addition to assisting in diagnosis, it can also help determine the activity of the embryo to guide treatment. In ectopic pregnancy, the blood β-HCG level is usually lower than that in normal intrauterine pregnancy. After conservative medical treatment or surgery, monitor blood beta-HCG levels to detect persistent ectopic pregnancy early.

3. Blood progesterone measurement: The progesterone level in patients with ectopic pregnancy is low, which can also be used as an indicator for diagnosing early ectopic pregnancy. The progesterone value in early pregnancy is relatively stable. For example, a progesterone value <45 nmol/L (15ng/ml) at 8 weeks of pregnancy indicates ectopic pregnancy or corpus luteum hypoplasia, with a sensitivity of 95%. There is overlap between normal and abnormal pregnancy serum progesterone levels, and it is difficult to determine the absolute critical value between them. It is for reference only. Developed countries include progesterone as a routine monitoring indicator for ectopic pregnancy.

4. Ultrasound examination: Vaginal ultrasound is better than abdominal ultrasound, with an accuracy rate of 70-94% for diagnosing ectopic pregnancy. The diagnosis can be confirmed by seeing a gestational sac ("fallopian tube ring") or fetal heartbeat in the fallopian tube. For those with a history of cesarean section, the anterior wall scar should be observed in particular to avoid missing the diagnosis of scar pregnancy. If the serum β-HCG exceeds 2000mIU/ml, if it is an intrauterine pregnancy, vaginal ultrasound can detect the gestational sac, otherwise you should be alert to ectopic pregnancy. Fluid dark areas in the pelvic and abdominal cavities are helpful for diagnosis.

5. Laparoscopy: It is the "gold standard" for diagnosing tubal pregnancy, but it is an invasive method with high cost. While making a clear diagnosis, endoscopic surgery can be performed, avoiding the blindness of open surgery. It has less trauma and faster recovery, and is widely used in hospitals with the necessary conditions. For specific methods, please refer to the "Laparoscopy" section of this manual.

6. Endometrial pathological examination: For patients with heavy vaginal bleeding and ultrasound showing heterogeneous endometrial thickening or cystic areas, a diagnostic curettage can be performed. If the scrapings contain villi, it can be confirmed as intrauterine pregnancy or abortion. Otherwise, the patient should send the sample for pathological examination. If only decidua is found without villi, it will help diagnose tubal pregnancy. For undiagnosed ectopic pregnancy, serum β-HCG can be rechecked 24 hours after curettage. If there is no significant decrease or increase compared to before the operation, the diagnosis is supported. In recent years, the popularization of assisted reproductive technology has significantly increased the incidence of heterotopic pregnancy, and we should be highly vigilant.