Obstetrics
Screening for Preeclampsia
Preeclampsia is a specific and often severe complication that develops in the second half of pregnancy.
It is characterized by increased blood pressure and presence of protein in the mother's urine (proteinuria).
In severe preeclampsia, a number of major maternal organs and systems are usually affected.
In addition, delayed fetal growth (fetal growth restriction - FGR) is often observed due to the abnormal distribution of blood to the placenta.
Preeclampsia is an important factor that increases the perinatal and maternal morbidity and mortality in modern obstetrics.
Pre-eclampsia and/or FGR can develop later in gestation, regardless of the blood pressure measurements before the beginning or in the first half of the pregnancy.
Accompanying chronic disease such as arterial hypertension, renal or autoimmune disease (systemic lupus erythematosus, antiphospholipid syndrome), thrombophilia, positive family history for preeclampsia in a previous pregnancy, etc., are all well known risk factors.
Prenatal screening for preeclampsia at 12-13+6 w. g. is based on a complex combination of anamnestic data, ultrasound measurement of blood flow in the uterine arteries, laboratory examination (blood sample) and measurement of the mother's blood pressure.
In this way, the risk for development of preeclampsia and fetal growth restriction in later gestation is adequately assessed.
Two hormones are investigated in the blood sample at 12-13+6 w.g. - the placental growth factor (PlGF) and the pregnancy-associated plasma protein A (PAPP-A).
Prenatal screening for pre-eclampsia can also be performed in late gestation (at 18-23 w.g.). However, then it is solely based on ultrasound measurement of blood flow in the uterine arteries (without a blood sample).
Combined first trimester prenatal screening for preeclampsia at 12-13+6 w.g. has a significantly higher sensitivity than the simple second trimester measurement of the blood flow in the uterine arteries. This is due to the fact that it includes a combination of several independent (physical, ultrasound and biochemical) parameters.
Combined first trimester screening for preeclampsia identifies about 90% of women at high risk for development of early preeclampsia (< 34 w.g.).
In order to plan and perform combined first trimester prenatal screening for pre-eclampsia at MC MARKOVS at 12+0-13+6 w.g. the following conditions should be observed:
- The patient should be acquainted with the aim, possibilities and limitations of the screening test - information about this can be provided by the fetal medicine specialist at MC MARKOVS during the fetal anatomy scan;
- The pregnancy should be between 12+0-13+6 w. g. and the first trimester scan should be planned at MC MARKOVS ;
- In the course of the examination Doppler examination of the blood flow of the uterine arteries will be performed;
- The patient history will be taken during or after the fetal anatomy scan and several points of interest will be specified: absence or presence of accompanying chronic disease, number of pregnancies, presence of complications in previous pregnancies, presence of first-degree relatives (mother or sister) who have developed preeclampsia, etc.;
- Measurement of blood pressure, height and weight;
- Blood sample (5 ml) will be drawn in order to test for two hormones - placental growth factor (PlGF) and pregnancy-associated plasma protein A (PAPP-A).
The results of the combined first trimester screening are provided in the form of an individual quantitative assessment of risk for development of preeclampsia and fetal growth restriction is calculated.
Usually, the results are ready in a few working days and then they are consulted by the fetal medicine specialist.
If the calculated risk for preeclampsia is higher than 1:150 (for example, 1:100) oral intake of 150 mg of Aspirin until 34-36 w.g. is usually recommended. In this way, the risk for development of preeclampsia before 32 w.g. is decreased by over 80%.
In some specific cases (with very low hormone values) your doctor may recommend oral intake of Aspirin, regardless of the results of the combined prenatal screening test.
ATTENTION
In case you plan to perform a combined (ultrasound and biochemical screening) for chromosomal fetal abnormalities and preeclampsia, you should schedule your appointment at MC MARKOVS between 08.00 and 16.00h.
The laboratory at MC MARKOVS has limited working hours from 08:00 to 16:00h every working day.
For more information about the possibilities to screen for preeclampsia at MC MARKOVS, you can contact your doctor or call at the registration desk.
Specialists
Prof. Dr. Dimiter Markov, Ph.D. Obstetrician-gynecologist
Dr. Elena Pavlova, Ph.D. Obstetrician-gynecologist
Dr. Dilyana Atanasova, Ph.D. Obstetrician-gynecologist
Dr. Ivelina Dimitrova Obstetrician-gynecologist
Dr. Veneta Stoykova, Ph.D. Obstetrician-gynecologist
Dr Ina Giosheva Obstetrician-gynecologist