(RxWiki News) A life-threatening condition in women is an ectopic pregnancy. However, it can be difficult for a woman to know if she has become pregnant and that the embryo has not implanted in her uterus.
A recent study looked at the best methods for accurately identifying an ectopic pregnancy.
The researchers found that using a transvaginal ultrasound to look for a lump of tissue is the most effective and accurate method.
A transvaginal ultrasound involves creating an image from an instrument inserted in a woman's vagina.
"See an OB/GYN if you experience unusual bleeding."
The study, led by John Crochet, MD, of the Center for Reproductive Medicine in Webster, Texas, aimed to determine the best method for diagnosing an ectopic pregnancy in women.
An ectopic pregnancy occurs when the sperm fertilizes an egg that does not implant in the uterus. Usually, the embryo remains in the fallopian tubes.
Ectopic pregnancies almost never will be able to come to term and can be life-threatening. The sooner they are found, the more likely a woman will survive without serious long-term issues.
The researchers reviewed medical research databases from 1965 through December 2012 for all papers related to diagnosing ectopic pregnancies.
They identified 14 studies that each involved at least 100 or more pregnant women and met their other requirements. Together, the studies included 12,101 participants.
The other requirements for the studies were that they followed women (instead of looking back at previous cases) who had abdominal pain or vaginal bleeding.
The studies also needed to include data on the patient's history, a physical exam, their lab results and the results of standard sonograms. A sonogram, also called an ultrasound, involves using sound waves to create an image of the inside of a part of the body.
This information's use for diagnosis had to be compared to the usefulness of clinical follow-up for all future pregnancies or the use of transvaginal ultrasounds.
A transvaginal ultrasound is an ultrasound done using an instrument inserted into the vagina, rather than using an instrument on a woman's abdomen.
The researchers found that several symptoms increased the likelihood that a woman would have an ectopic pregnancy.
These symptoms included tenderness on a woman's cervix during a physical exam, finding a lump of tissue in the ovary or fallopian tube without seeing a pregnancy in the uterus and tenderness on that tissue lump.
The best way to see if that lump of tissue was present was through a transvaginal ultrasound, the researchers found. Not finding a lump of tissue on a transvaginal sonogram, even with the tenderness symptom, meant the risk of an ectopic pregnancy was very low.
The studies also revealed that there is not currently a known level of hCG in a woman's blood or urine that indicates an ectopic pregnancy.
The levels of hormone hCG, which stands for human chorionic gonadotropin, are often used as an indication of pregnancy in women.
"Transvaginal sonography is the single best diagnostic [method] for evaluating women with suspected ectopic pregnancy," the researchers wrote. "The presence of abdominal pain or vaginal bleeding during early pregnancy should prompt a transvaginal sonogram and quantitative serum hCG testing."
This finding matches up with the practices in the office of Jen Mushtaler, MD, an OBGYN in Austin, Texas, and a dailyRx expert.
"Unfortunately, a single HCG level does not determine if a pregnancy is ectopic, non-viable or a viable intrauterine pregnancy," Dr. Mushtaler said.
"In our clinical practice, we use a combination of serial HCG levels taken 48 hours apart, a progesterone hormone level and transvaginal ultrasound to help us determine the status of an early pregnancy," she said.
The study was published April 24 in JAMA. No external funding was listed for the study, and the authors declared no conflicts of interest.