Does unexplained second-trimester (15 to 20 weeks' gestation) maternal serum alpha-fetoprotein elevation presage adverse perinatal outcome?

Article Abstract:

Testing for elevated maternal levels of alpha-fetoprotein (AFP), a plasma protein produced by the fetus, to determine risk of neural tube (structural beginning of central nervous system) defects of the fetus is a common practice. However, elevated levels are often associated with other situations such as twins, wrong gestational age, or fetal death, rather than with neural tube defects. In many cases, AFP levels are elevated with no known cause. Some reports suggest that in these cases, there may an increase in pregnancy complications such as preeclampsia or poor outcomes such as low-birth-weight infants. However, the research supporting this association is limited, and bias in the way studies have been conducted may be responsible for these findings. To determine if elevated AFP levels during or following the second trimester are related to poorer outcomes, 279 women from an area with a high frequency of obstetric complications were studied. AFP levels rose until 32 weeks of gestation and then progressed at a slower rate. Third trimester levels were more variable, but still useful. Of 279 women, 270 with normal second trimester AFP values had similar third trimester values. Of six women with elevated second trimester values who had singleton pregnancies, none had elevated third trimester values, even though two had poor outcomes. In another group of 24 women who had elevated AFP in the third trimester, two had fetal deaths and others experienced complications. The study suggests that AFP levels in the second and third trimester are not related, but that elevated levels in the third trimester may be somewhat predictive of complications. The study does not recommend rigorous screening of women with unexplained second trimester AFP levels. Addition research with properly designed studies with larger sample sizes are needed before the significance of elevated AFP levels is fully understood. (Consumer Summary produced by Reliance Medical Information, Inc.)

Measurement, Pregnancy, Complications of, Pregnancy complications, Alpha fetoproteins

---

Dilation and evacuation for second-trimester genetic pregnancy termination

Article Abstract:

Prenatal tests are used to diagnose genetic abnormalities in the fetus. Many abnormalities are initially detected by fetal ultrasonographic imaging and maternal blood tests performed after the twelfth week of pregnancy, often between the fifteenth and twenty-fourth weeks of gestation. If the mother decides to terminate the pregnancy, a second-trimester abortion is performed. The most frequently used technique of pregnancy termination during the second trimester involves inducing labor by instilling salt solution, urea or prostaglandins into the amniotic sac, or by introducing a prostaglandin suppository in the vagina to induce contractions. Another method involves dilating the cervix and evacuating the products of conception, which is called dilation and evacuation (D&E). Although D&E is less risky, labor induction is more commonly used. Perhaps this is because geneticists are reluctant to recommend D&E since it is thought that the process of D&E alters the products of conception, making it difficult to confirm the diagnosis of genetic abnormalities. However, a D&E procedure does not require hospitalization, costs less, is less stressful and is psychologically easier to tolerate. The ability to confirm prenatal diagnosis after D&E was studied among 60 patients with genetic abnormalities of the fetus; they had D&E between 14 and 22 weeks gestation. The prenatal diagnosis was successfully confirmed in all 60 cases. Therefore, D&E is the preferred method of pregnancy termination in the second trimester, even when the reason for termination is genetic abnormalities. (Consumer Summary produced by Reliance Medical Information, Inc.)

Methods, Reports, Diagnosis, Birth defects, Abortion, Prenatal diagnosis

---

Isolated fetal choroid plexus cysts and trisomy 18: a review and meta-analysis

Article Abstract:

The ultrasonographic finding of cysts in the choroid plexus of the fetal brain does not warrant amniocentesis to rule out trisomy 18 in the absence of other anomalies. Trisomy 18 is a genetic defect. The association between the presence of choroid plexus cysts as an isolated anomaly and trisomy 18 was examined by pooling data from 74 fetuses with such cysts scanned at the University of Tennessee with 674 cases found among 12 other studies. Overall, two out of 748 fetuses, or 1/374, had trisomy 18. This agreed closely with a calculation of the likelihood that a fetus with choroid plexus cysts, but no other anomalies, would have trisomy 18. The finding of choroid plexus cysts indicates the need for a detailed ultrasonographic assessment. If no other anomalies are found, the risk does not warrant a general recommendation for amniocentesis. However, couples should be counseled as to the risks of fetal loss caused by amniocentesis versus the risk of undetected trisomy 18.

Abnormalities, Fetus, Diseases, Trisomy, Choroid plexus

Similar abstracts:

• Abstracts: Colon cancer in pregnancy with elevated maternal serum alpha-fetoprotein level at presentation. Prenatal diagnosis of a chest wall mass with ultrasonography and Doppler velocimetry
• Abstracts: Absence of need for amniocentesis in patients with elevated levels of maternal serum alpha-fetoprotein and normal ultrasonographic examinations. part 2
• Abstracts: Risk of fetal chromosomal anomalies in patients with elevated maternal serum alpha-fetoprotein. Elevated maternal serum alpha-fetoprotein concentration and fetal chromosomal abnormalities

This website is not affiliated with document authors or copyright owners. This page is provided for informational purposes only. Unintentional errors are possible.