Amniocentesis and chorionic villus sampling for prenatal diagnosis

BACKGROUND

A major disadvantage of second trimester amniocentesis is that the result is usually available only after 18 weeks' gestation. Chorionic villus sampling (CVS) and early amniocentesis can be done between 9 and 14 weeks and offer an earlier alternative.

OBJECTIVES

The objective was to assess comparative safety and accuracy of second trimester amniocentesis, early amniocentesis, transcervical and transabdominal CVS.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (March 2003) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 1, 2002).

SELECTION CRITERIA

All randomised trials comparing amniocentesis and CVS.

DATA COLLECTION AND ANALYSIS

Two reviewers assessed eligibility and trial quality and performed data extraction. We analysed the data using RevMan software.

MAIN RESULTS

A total of 14 randomised studies have been included. In a low risk population with a background pregnancy loss of around 2%, a second trimester amniocentesis will increase this risk by another 1%. This difference did not reach statistical significance, but the increase in spontaneous miscarriages following second trimester amniocentesis compared with controls (no amniocentesis) did (2.1% versus 1.3%; relative risk (RR) 1.02 to 2.52). Early amniocentesis is not a safe early alternative to second trimester amniocentesis because of increased pregnancy loss (7.6% versus 5.9%; RR 1.29, 95% CI 1.03 to 1.61) and higher incidence of talipes compared to CVS (1.8% versus 0.2%; RR 6.43, 95% CI 1.68 to 24.64).Compared with second trimester amniocentesis, transcervical CVS carries a significantly higher risk of pregnancy loss (14.5% versus 11%; RR 1.40, 95% CI 1.09 to 1.81) and spontaneous miscarriage (12.9% versus 9.4%; RR 1.50, 95% CI 1.07 to 2.11). One study compared transabdominal CVS with second trimester amniocentesis and found no significant difference in the total pregnancy loss between the two procedures (6.3% versus 7%). Transcervical CVS is more technically demanding than transabdominal CVS with more failures to obtain sample and more multiple insertions.

REVIEWER'S CONCLUSIONS

Second trimester amniocentesis is safer than transcervical CVS and early amniocentesis. If earlier diagnosis is required, transabdominal CVS is preferable to early amniocentesis or transcervical CVS. In circumstances where transabdominal CVS may be technically difficult the preferred options are transcervical CVS in the first trimester or second trimester amniocentesis.

Ultrasound for fetal assessment in early pregnancy

BACKGROUND

Diagnostic ultrasound is a sophisticated electronic technology, which utilises pulses of high frequency sound to produce an image. Diagnostic ultrasound examination may be employed in a variety of specific circumstances during pregnancy such as after clinical complications, or where there are concerns about fetal growth. Because adverse outcomes may also occur in pregnancies without clear risk factors, assumptions have been made that routine ultrasound in all pregnancies will prove beneficial by enabling earlier detection and improved management of pregnancy complications. Routine screening may be planned for early pregnancy, late gestation, or both. The focus of this review is routine early pregnancy ultrasound.

OBJECTIVES

To assess whether routine early pregnancy ultrasound for fetal assessment (i.e. its use as a screening technique) influences the diagnosis of fetal malformations, multiple pregnancies, the rate of clinical interventions, and the incidence of adverse fetal outcome when compared with the selective use of early pregnancy ultrasound (for specific indications).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 2009).

SELECTION CRITERIA

Published, unpublished, and ongoing randomised controlled trials that compared outcomes in women who experienced routine versus selective early pregnancy ultrasound (i.e. less than 24 weeks' gestation). We have included quasi-randomised trials.

DATA COLLECTION AND ANALYSIS

Two review authors independently extracted data for each included study. We used the Review Manager software to enter and analyse data.

MAIN RESULTS

Routine/revealed ultrasound versus selective ultrasound/concealed: 11 trials including 37505 women. Ultrasound for fetal assessment in early pregnancy reduces the failure to detect multiple pregnancy by 24 weeks' gestation (risk ratio (RR) 0.07, 95% confidence interval (CI) 0.03 to 0.17). Routine scan is associated with a reduction in inductions of labour for 'post term' pregnancy (RR 0.59, 95% CI 0.42 to 0.83). Routine scans do not seem to be associated with reductions in adverse outcomes for babies or in health service use by mothers and babies. Long-term follow up of children exposed to scan in utero does not indicate that scans have a detrimental effect on children's physical or cognitive development.

AUTHORS' CONCLUSIONS

Early ultrasound improves the early detection of multiple pregnancies and improved gestational dating may result in fewer inductions for post maturity. Caution needs to be exercised in interpreting the results of aspects of this review in view of the fact that there is considerable variability in both the timing and the number of scans women received.

Expectant care versus surgical treatment for miscarriage

BACKGROUND

Miscarriage is a common complication of early pregnancy that can have both medical and psychological consequences such as depression and anxiety. The need for routine surgical evacuation with miscarriage has been questioned because of potential complications such as cervical trauma, uterine perforation, hemorrhage, or infection.

OBJECTIVES

To compare the safety and effectiveness of expectant management versus surgical treatment for early pregnancy failure.

SEARCH METHODS

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (9 February 2012), the Cochrane Central Register of Controlled Trials (The Cochrane Library 2011, Issue 4 of 4), PubMed (2005 to 11 January 2012), POPLINE (inception to 11 January 2012), LILACS (2005 to 11 January 2012) and reference lists of retrieved studies.

SELECTION CRITERIA

Randomized trials comparing expectant care and surgical treatment (vacuum aspiration or dilation and curettage) for miscarriage were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

Two review authors assessed trial quality and extracted data. We contacted study authors for additional information. For dichotomous data, we calculated the Mantel-Haenszel risk ratio (RR) with 95% confidence interval (CI). For continuous data, we computed the mean difference (MD) and 95% CI. We entered additional data such as medians into 'Other data' tables.

MAIN RESULTS

We included seven trials with 1521 participants in this review. The expectant-care group was more likely to have an incomplete miscarriage by two weeks (RR 3.98; 95% CI 2.94 to 5.38) or by six to eight weeks (RR 2.56; 95% CI 1.15 to 5.69). The need for unplanned surgical treatment was greater for the expectant-care group (RR 7.35; 95% CI 5.04 to 10.72). The mean percentage needing surgical management in the expectant-care group was 28%, while 4% of the surgical-treatment group needed additional surgery. The expectant-care group had more days of bleeding (MD 1.59; 95% CI 0.74 to 2.45). Further, more of the expectant-care group needed transfusion (RR 6.45; 95% CI 1.21 to 34.42). The mean percentage needing blood transfusion was 1.4% for expectant care compared with none for surgical management. Results were mixed for pain. Diagnosis of infection was similar for the two groups (RR 0.63; 95% CI 0.36 to 1.12), as were results for various psychological outcomes. Pregnancy data were limited. Costs were lower for the expectant-care group (MD -499.10; 95% CI -613.04 to -385.16; in UK pounds sterling).

AUTHORS' CONCLUSIONS

Expectant management led to a higher risk of incomplete miscarriage, need for unplanned (or additional) surgical emptying of the uterus, bleeding and need for transfusion. Risk of infection and psychological outcomes were similar for both groups. Costs were lower for expectant management. Given the lack of clear superiority of either approach, the woman's preference should be important in decision making. Pharmacological ('medical') management has added choices for women and their clinicians and has been examined in other reviews.

Spontaneous uterine rupture in the first trimester: a case report

Uterine rupture is one of the most feared obstetric complications affecting the pregnant woman and fetus. Most of the cases have various risk factors and mainly occur during the second or third trimester. However, spontaneous uterine rupture during the first trimester is extremely rare. We experienced a case of spontaneous uterine rupture in a 36-yr-old multiparous woman without definite risk factors. The initial impression was a hemoperitoneum of an unknown origin with normal early pregnancy. Intensive surgical method would be needed for accurate diagnosis and immediate management in bad situation by hemoperitoneum even though a patient was early pregnancy.

Medical treatments for incomplete miscarriage (less than 24 weeks)

BACKGROUND

Miscarriage occurs in 10% to 15% of pregnancies. The traditional treatment, after miscarriage, has been to perform surgery to remove any remaining pregnancy tissues in the uterus. However, it has been suggested that drug-based medical treatments, or expectant care (no treatment), may also be effective, safe and acceptable.

OBJECTIVES

To assess the effectiveness, safety and acceptability of any medical treatment for early incomplete miscarriage (before 24 weeks).

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (September 2009).

SELECTION CRITERIA

Randomised controlled trials comparing medical treatment with expectant care or surgery. Quasi-randomised trials were excluded.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the studies for inclusion, assessed risk of bias and carried out data extraction. Data entry was checked.

MAIN RESULTS

Fifteen studies (2750 women) were included, there were no studies on women over 13 weeks' gestation. Studies addressed a number of comparisons and data are therefore limited.Three trials compared misoprostol treatment (all vaginally administered) with expectant care. There was no significant difference in complete miscarriage (average risk ratio (RR) 1.23, 95% confidence interval (CI) 0.72 to 2.10; two studies, 150 women), or in the need for surgical evacuation (average RR 0.62, 95% CI 0.17 to 2.26; two studies, 308 women). There were few data on 'deaths or serious complications'.Nine studies involving 1766 women addressed the comparison of misoprostol (four oral, four vaginal, one vaginal + oral) with surgical evacuation. There was no statistically significant difference in complete miscarriage (average RR 0.96, 95% CI 0.92 to 1.00, eight studies, 1377 women) with success rate high for both methods. Overall, there were fewer surgical evacuations with misoprostol (average RR 0.07, 95% CI 0.03 to 0.18; eight studies, 1538 women) but more unplanned procedures (average RR 6.32, 95% CI 2.90 to 13.77; six studies, 1158 women). There were few data on 'deaths or serious complications'. Limited evidence suggests that women generally seem satisfied with their care. Long-term follow up from one included study identified no difference in subsequent fertility between the three approaches.

AUTHORS' CONCLUSIONS

The available evidence suggests that medical treatment, with misoprostol, and expectant care are both acceptable alternatives to routine surgical evacuation given the availability of health service resources to support all three approaches. Women experiencing miscarriage at less than 13 weeks should be offered an informed choice.

The distribution of fetal nuchal translucency thickness in normal Korean fetuses

The aim of present study was to establish normative data for the distribution of nuchal translucency (NT) thickness in normal Korean fetuses. The data were collected from pregnant women with singleton pregnancies in whom fetal ultrasound was performed and the fetal NT thickness was measured between 11 and 14 weeks of gestation. Among them, a total of 2,577 fetuses with a known normal outcome were included in this study. The distribution of multiple of median (MoM) values of the NT thickness with crown-rump length (CRL) in 10-mm intervals and the 95th percentile of MoM were calculated with the linear regression method. The present study showed that NT measurements increase with increasing CRL and a false positive rate increases with increasing gestational age. Therefore, a fixed cut-off point through the first trimester was not appropriate and each NT measurement should be examined according to the gestational age. The present study offers normative data of the fetal NT thickness in a Korean population, which can be used as reference for screening chromosomal aberrations or other congenital abnormalities in the first trimester.

First and second trimester serum tests with and without first trimester ultrasound tests for Down's syndrome screening

BACKGROUND

Down's syndrome occurs when a person has three copies of chromosome 21 (or the specific area of chromosome 21 implicated in causing Down's syndrome) rather than two. It is the commonest congenital cause of mental disability. Non-invasive screening based on biochemical analysis of maternal serum or urine, or fetal ultrasound measurements, allows estimates of the risk of a pregnancy being affected and provides information to guide decisions about definitive testing.  Before agreeing to screening tests, parents need to be fully informed about the risks, benefits and possible consequences of such a test. This includes subsequent choices for further tests they may face, and the implications of both false positive (i.e. invasive diagnostic testing, and the possibility that a miscarried fetus may be chromosomally normal) and false negative screening tests (i.e. a fetus with Down's syndrome will be missed). The decisions that may be faced by expectant parents inevitably engender a high level of anxiety at all stages of the screening process, and the outcomes of screening can be associated with considerable physical and psychological morbidity. No screening test can predict the severity of problems a person with Down's syndrome will have.

OBJECTIVES

To estimate and compare the accuracy of first and second trimester serum markers with and without first trimester ultrasound markers for the detection of Down's syndrome in the antenatal period, as combinations of markers.

SEARCH METHODS

We conducted a sensitive and comprehensive literature search of MEDLINE (1980 to 25 August 2011), Embase (1980 to 25 August 2011), BIOSIS via EDINA (1985 to 25 August 2011), CINAHL via OVID (1982 to 25 August 2011), the Database of Abstracts of Reviews of Effectiveness (the Cochrane Library 25 August 2011), MEDION (25 August 2011), the Database of Systematic Reviews and Meta-Analyses in Laboratory Medicine (25 August 2011), the National Research Register (Archived 2007), and Health Services Research Projects in Progress database (25 August 2011). We did not apply a diagnostic test search filter. We did forward citation searching in ISI citation indices, Google Scholar and PubMed 'related articles'. We also searched reference lists of retrieved articles SELECTION CRITERIA: Studies evaluating tests of combining first and second trimester maternal serum markers in women up to 24 weeks of gestation for Down's syndrome, with or without first trimester ultrasound markers, compared with a reference standard, either chromosomal verification or macroscopic postnatal inspection.

DATA COLLECTION AND ANALYSIS

Data were extracted as test positive/test negative results for Down's and non-Down's pregnancies allowing estimation of detection rates (sensitivity) and false positive rates (1-specificity). We performed quality assessment according to QUADAS criteria. We used hierarchical summary ROC meta-analytical methods to analyse test performance and compare test accuracy. Analysis of studies allowing direct comparison between tests was undertaken. We investigated the impact of maternal age on test performance in subgroup analyses.

MAIN RESULTS

Twenty-two studies (reported in 25 publications) involving 228,615 pregnancies (including 1067 with Down's syndrome) were included. Studies were generally high quality, although differential verification was common with invasive testing of only high risk pregnancies. Ten studies made direct comparisons between tests. Thirty-two different test combinations were evaluated formed from combinations of eight different tests and maternal age; first trimester nuchal translucency (NT) and the serum markers AFP, uE3, total hCG, free βhCG, Inhibin A, PAPP-A and ADAM 12. We looked at tests combining first and second trimester markers with or without ultrasound as complete tests, and we also examined stepwise and contingent strategies.Meta-analysis of the six most frequently evaluated test combinations showed that a test strategy involving maternal age and a combination of first trimester NT and PAPP-A, and second trimester total hCG, uE3, AFP and Inhibin A significantly outperformed other test combinations that involved only one serum marker or NT in the first trimester, detecting about nine out of every 10 Down's syndrome pregnancies at a 5% false positive rate. However, the evidence was limited in terms of the number of studies evaluating this strategy, and we therefore cannot recommend one single screening strategy.

AUTHORS' CONCLUSIONS

Tests involving first trimester ultrasound with first and second trimester serum markers in combination with maternal age are significantly better than those without ultrasound, or those evaluating first trimester ultrasound in combination with second trimester serum markers, without first trimester serum markers. We cannot make recommendations about a specific strategy on the basis of the small number of studies available.

Perioperative antibiotics to prevent infection after first-trimester abortion

BACKGROUND

There are two main strategies for the prevention of post-abortal upper genital tract infection: antibiotics given around the time of surgery for all women; and 'screen-and-treat', in which all women presenting for abortion are screened for genital infections and those with positive results are treated.

OBJECTIVES

To determine:1. the effectiveness of antibiotic prophylaxis in preventing post-abortal upper genital tract infection; 2. the most effective antibiotic regimen; 3. the most effective strategy.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), PubMed, EMBASE, POPLINE and LILACS. The search was last updated in May 2011.

SELECTION CRITERIA

Randomised controlled trials (RCTs) in any language including women undergoing induced first trimester surgical or medical abortion, comparing: 1) any antibiotic regimen to placebo, nothing, or another antibiotic; 2) screen-and-treat versus antibiotics. The primary outcome was the proportion of women diagnosed with post-abortal upper genital tract infection.

DATA COLLECTION AND ANALYSIS

Two reviewers independently selected references and extracted data. We calculated risk ratios (RR) with 95% confidence intervals (CI). We used meta-analysis where appropriate and examined between trial heterogeneity using the I(2) statistic. In the presence of between trial heterogeneity we also estimated the 95% prediction interval (PI).

MAIN RESULTS

A total of 703 unique items was identified. We included 19 RCTs. There was evidence of small study biases (Egger test, P = 0.002). In 15 placebo-controlled RCTs there was an effect of antibiotic prophylaxis (pooled RR 0.59, 95% CI 0.46 to 0.75, 95% PI 0.30 to 1.14, I(2) = 39%). There were insufficient data (three trials) to determine whether one regimen was superior to another. In one trial, the incidence of post-abortal upper genital tract infection was higher in women allocated to the screen-and-treat strategy (RR 1.53, 95% CI 0.99 to 2.36).

AUTHORS' CONCLUSIONS

Antibiotic prophylaxis at the time of first trimester surgical abortion is effective in preventing post-abortal upper genital tract infection. Evidence of between trial heterogeneity suggests that the effect might not apply to all settings, population groups or interventions.This review did not determine the most effective antibiotic prophylaxis regimen. Antibiotic choice should take into account the local epidemiology of genital tract infections, including sexually transmitted infections.Further RCTs comparing different antibiotics or combinations of antibiotics with each other would be useful. Such trials could be done in low and middle income countries and where the prevalence of genital tract infections in women presenting for abortion is high.

WITHDRAWN: Interventions for nausea and vomiting in early pregnancy

BACKGROUND

Nausea and vomiting are the most common symptoms experienced in early pregnancy, with nausea affecting between 70 and 85% of women. About half of pregnant women experience vomiting.

OBJECTIVES

To assess the effects of different methods of treating nausea and vomiting in early pregnancy.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register (December 2002) and the Cochrane Central Register of Controlled Trials (The Cochrane Library, Issue 4, 2002).

SELECTION CRITERIA

Randomised trials of any treatment for nausea and/or vomiting in early pregnancy.

DATA COLLECTION AND ANALYSIS

Two reviewers assessed the trial quality and extracted the data independently.

MAIN RESULTS

Twenty-eight trials met the inclusion criteria. For milder degrees of nausea and vomiting, 21 trials were included. These trials were of variable quality. Nausea treatments were: different antihistamine medications, vitamin B6 (pyridoxine), the combination tablet Debendox (Bendectin), P6 acupressure and ginger. For hyperemesis gravidarum, seven trials were identified testing treatments with oral ginger root extract, oral or injected corticosteroids or injected adrenocorticotropic hormone (ACTH), intravenous diazepam and acupuncture. Based on 12 trials, there was an overall reduction in nausea from anti-emetic medication (odds ratio 0.16, 95% confidence interval 0.08 to 0.33).

AUTHORS' CONCLUSIONS

Anti-emetic medication appears to reduce the frequency of nausea in early pregnancy. There is some evidence of adverse effects, but there is very little information on effects on fetal outcomes from randomised controlled trials. Of newer treatments, pyridoxine (vitamin B6) appears to be more effective in reducing the severity of nausea. The results from trials of P6 acupressure are equivocal. No trials of treatments for hyperemesis gravidarum show any evidence of benefit. Evidence from observational studies suggests no evidence of teratogenicity from any of these treatments.

Evaluation of perineal muscle strength in the first trimester of pregnancy

OBJECTIVES

to analyze the Pelvic Floor Muscle Strength (PFMS) of pregnant women with one or more vaginal or cesarean deliveries; to compare the PFMS of these with pregnant women with the PFMS of primiparous women.

METHODS

cross-sectional study with women up to 12 weeks pregnant, performed in Itapecerica da Serra, São Paulo state, from December 2012 to May 2013. The sample consisted of 110 pregnant women with one or more vaginal deliveries or cesarean sections and 110 primigravidae. The PFMS was evaluated by perineometry (Peritron(tm)) and vaginal digital palpation (modified Oxford scale).

RESULTS

the average PFMS in pregnant women with a history of vaginal delivery or cesarean section was 33.4 (SD=21.2) cmH2O. From the Oxford scale, 75.4% of the pregnant women with previous vaginal or cesarean deliveries presented grade ≤ 2, and 5.5% grade ≥ 4; among the primiparae, 39.9% presented grade ≤ 2, and 50.9% grade ≥ 4, with a statistically significant difference (p<0.001). From the perineometry, there was no statistically significant difference between the PFMS and age, type of delivery, parity, body mass index, and genitourinary tract symptoms, however, there was a statistically significant difference between the pregnant women with and without a history of episiotomy (p=0.04). In the palpation, none of the variables showed a statistically significant difference.

CONCLUSION

pregnancy and childbirth can reduce the PFMS.

Nitric oxide donors for cervical ripening in first-trimester surgical abortion

BACKGROUND

Cervical priming before first-trimester surgical abortion is recommended in certain groups of women. Nitric oxide (NO) donors induce cervical ripening without uterine contractions, but the efficacy and side effects are of concern.

OBJECTIVES

To evaluate NO donors for cervical ripening before first-trimester surgical abortion, in terms of efficacy, side effects, and reduction of complications.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, and POPLINE. We also searched reference lists of retrieved papers. We contacted experts in the field for information on both published and unpublished trials.

SELECTION CRITERIA

Randomised controlled trials comparing NO donors alone or in combination with other methods for cervical ripening in first-trimester surgical abortion.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected and extracted the data onto a data extraction form. We processed the data using Review Manager (RevMan 5) software.

MAIN RESULTS

We included 9 studies involving 766 participants. There were no serious complications (infection requiring antibiotic treatment, blood transfusion, complications requiring unintended operation, cervical injury, uterine perforation, death or serious morbidity) in the included trials.NO donors were more effective in cervical ripening when compared with placebo or no treatment. Baseline cervical dilatation before the procedure was higher in NO donors group (mean difference (MD) 0.30, 95% confidence interval (CI) 0.01 to 0.58) The cumulative force required to dilate the cervix to 8 mm (MD -4.29, 95% CI -9.92 to 1.35), headache (risk ratio (RR) 1.73, 95% CI 0.86 to 3.46), abdominal pain (RR 0.87, 95% CI 0.50 to 1.50), or patient satisfaction (RR 0.95, 95% CI 0.84 to 1.07) were not different. More nausea and vomiting occurred in the women who received a NO donor (RR 2.62, 95% CI 1.07 to 6.45).NO donors were inferior to prostaglandins for cervical ripening. The cumulative force required to dilate the cervix to 8 mm to 9 mm was higher (MD 13.12, 95% CI 9.72 to 16.52), and baseline cervical dilatation was less (MD -0.73, 95% CI -1.01 to -0.45) in the NO donor group. However, the probability of dilation greater than 8 mm at three hours was higher in the NO donor group (RR 6.67, 95% CI 2.21 to 20.09). Side effects including headache (RR 5.13, 95% CI 3.29 to 8.00), palpitation (RR 3.43, 95% CI 1.64 to 7.15), dizziness (RR 3.29, 95% CI 1.46 to 7.41), and intraoperative blood loss (MD 33.59 ml, 95% CI 24.50 to 42.67) were also higher. However, abdominal pain (RR 0.33, 95% CI 0.25 to 0.44) and vaginal bleeding (RR 0.14, 95% CI 0.07 to 0.27) were less in the NO donor group. No difference for nausea/vomiting in both groups(RR 1.17, 95% CI 0.94 to 1.46). Patient satisfaction was not different.One trial compared a NO donor with a NO donor plus prostaglandin. The cumulative force required to dilate the cervix to 8 mm was higher (MD 14.50, 95% CI 0.50 to 28.50) in the NO donor group. There was no difference in headache (RR 0.88, 95% CI 0.38 to 2.00), abdominal pain (RR 0.14, 95% CI 0.02 to 1.07), or intraoperative blood loss (MD -50, 95% CI -164.19 to 64.19).

AUTHORS' CONCLUSIONS

NO donors are superior to placebo or no treatment, but inferior to prostaglandins for first-trimester cervical ripening, and associated with more side effects.

Committee Opinion No. 418: The Complete 11-14 Week Prenatal Sonographic Examination

OBJECTIVE

Sonography during the first trimester provides an opportunity to assess a pregnancy in its early stage. This document provides an opinion about the implementation and content of prenatal sonographic examinations at 11-14 weeks gestation in Canada.

TARGET POPULATION

Pregnant women at 11-14 weeks gestation.

BENEFITS, HARMS, AND COSTS

The 11-14 week prenatal sonographic examination can provide important information that may contribute to pregnancy management. It can be used to confirm viability, establish gestational age, determine the number of fetuses, assess the adnexa/ovaries, and, in a multiple pregnancy, assess chorionicity and amnionicity. Scanning also offers an opportunity to detect fetal abnormalities and perform aneuploidy screening by measuring the nuchal translucency thickness. It may be valuable in screening for preeclampsia and other obstetrical disorders (by combining uterine artery Doppler scanning with other bio-clinical markers) and for invasive placentation. There are no physical harms to mother or fetus from offering a routine 11-14 week prenatal sonographic examination, and there are no extra costs for patients.

EVIDENCE

Articles related to routine 11-14 week prenatal sonography were identified in a search of EMBASE and MEDLINE using the search terms first trimester ultrasound, nuchal translucency, and 11-14 week ultrasound. The search included all articles published on the topic until May 2019. Abstracts were reviewed by one author, and articles deemed relevant were then reviewed in full to determine whether to include them in the study. Articles that were not in English and articles that did not pertain to 11-14 week prenatal sonography were excluded.

INTENDED AUDIENCE

This document is intended for sonographers, midwives, family physicians, obstetricians, and maternal-fetal medicine specialists.

Systematic Review of the Effectiveness, Safety, and Acceptability of Mifepristone and Misoprostol for Medical Abortion in Low- and Middle-Income Countries

OBJECTIVE

Abortion-related complications remain one of the leading causes of maternal morbidity and mortality worldwide. Nearly half of all abortions are unsafe, and the vast majority of these occur in low- and middle-income countries. The use of mifepristone with misoprostol for medical abortion has been proposed and implemented to improve abortion safety.

DATA SOURCES

A systematic review of the literature was conducted in PubMed, Embase, Cochrane, and CINAHL.

STUDY SELECTION

Criteria for study inclusion were first-trimester abortion, use of mifepristone with misoprostol, and low- or middle-income country status as designated by the World Health Organization.

DATA EXTRACTION

Results for effectiveness, safety, acceptability, and qualitative information were assessed.

DATA SYNTHESIS

The literature search resulted in 181 eligible articles, 52 of which met our criteria for inclusion. A total of 34 publications reported effectiveness data on 25 385 medical abortions. The average effectiveness rate with mifepristone 200 mg and misoprostol 800 µg was 95% up to 63 days gestation. A sensitivity analysis was performed to assume that all women lost to follow-up failed treatment, and the recalculated effectiveness rate remained high at 93%. The average continuing pregnancy rate was 0.6%. A total of 22 publications reported safety and acceptability data on 17 381 medical abortions. Only 0.8% abortions required presentation to hospital, and 87% of patients found the side effects of treatment acceptable. Overall, 95% of women were satisfied with their medical abortion, 94% would choose the method again, and 94% would recommend this method to a friend. A total of 16 publications reported qualitative results and the majority supported positive patient experiences with medical abortion.

CONCLUSIONS

Mifepristone and misoprostol is highly effective, safe, and acceptable to women in low- and middle-income countries, making it a feasible option for reducing maternal morbidity and mortality worldwide.

Effects of an Early Pregnancy Assessment Clinic (EPAC) on the Management of Spontaneous Abortions

OBJECTIVE

Patients who experience spontaneous abortion often present to the emergency department (ED), which may restrict the physician's recommendations for and the patient's choice of therapy. With support provided by an early pregnancy assessment clinic (EPAC), expectant and medical management may become more feasible options for spontaneous abortion. This study aimed to compare the therapeutic choices before and after the establishment of an EPAC and hypothesized that the proportion of miscarriages treated expectantly or medically would increase.

METHODS

We conducted a retrospective cohort study that compared patients presenting to the ED and the EPAC with spontaneous abortion. We excluded patients with hemodynamic instability, complete abortions, ectopic pregnancies, and molar pregnancies. The primary outcome was the initial chosen treatment. The retrospective chart review included demographics, type of spontaneous abortion and management, procedural dictations, ED notes, and EPAC clinic documentation. Secondary end points included wait times, repeat visits, and success rates for the initial treatment option.

RESULTS

We reviewed 103 ED and 92 EPAC patient records. Patients in the ED were 1.52 times more likely to choose surgery over expectant or medical management (P = 0.004). Patients in the ED were 1.41 times more likely to have surgery as their final treatment compared with patients in the EPAC (P = 0.006). There were no significant differences in length of stay, number of visits required, or adverse outcomes.

CONCLUSION

Our study demonstrates that an EPAC results in more patients choosing and successfully being treated by expectant or medical management for spontaneous abortion.

Does Excess First- or Second-Trimester Weight Gain Predict Excess Total Gestational Weight Gain? A Multicentre Prospective Cohort Study

OBJECTIVES

Early excess gestational weight gain (GWG) has been examined as a predictor of total excess GWG in a few international studies; however, Canadian data are lacking. We sought to determine whether early (first- and second-trimester) excess GWG predicted total excess GWG.

METHODS

We conducted an a priori planned secondary analysis of a multicentre prospective study of English-speaking Ontario women with a singleton pregnancy between 8⁰ and 20⁶ weeks gestation. Our primary outcome was prediction of total excess GWG. We calculated the sensitivity, specificity, predictive values, and likelihood ratios, by body mass index (BMI), for excess first- and second-trimester GWG.

RESULTS

Of the 970 women who met the inclusion criteria, 387 and 754, had first- and second-trimester weights recorded in their antenatal record, respectively. For normal, overweight, and obese women, the sensitivity of excess first-trimester GWG for total excess gain was 66%, 68%, and 65%, respectively; and the specificity was 48%, 43%, and 36%, respectively. The sensitivity of excess second-trimester GWG for total excess gain for normal weight, overweight, and obese women was higher, at 92%, 96%, and 95%, respectively; while the specificity was low at 31%, 16%, and 29%, respectively.

CONCLUSION

In the first known Canadian study of early excess weight gain as the predictor of total GWG, we found that excess first-trimester GWG did not predict total excess GWG, but that the sensitivity of excess second-trimester GWG for excess total GWG was high across BMI categories.

Evaluation of embryonic posture using four-dimensional ultrasound and virtual reality

Aim

To assess the possibility of embryonic posture evaluation (=feasibility, reproducibility, variation) at rest at 9 weeks' (+0–6 days) gestational age (GA) using four‐dimensional ultrasound and virtual reality (VR) techniques. Moreover, it is hypothesized that embryonic posture shows variation at the same time point in an uneventful pregnancy.

Methods

In this explorative prospective cohort study, 23 pregnant women were recruited from the Rotterdam periconceptional cohort. A transvaginal four‐dimensional ultrasound examination of 30 min per pregnancy was performed between 9 and 10 weeks' GA. The acquired datasets were offline evaluated longitudinally (i.e. per frame) using VR techniques.

Results

The ultrasound data of 16 (70%) out of 23 pregnancies were eligible for evaluation. At rest the analysis of the embryonic posture was feasible and showed a strong (>80%) intraobserver and interobserver reproducibility for most body parts. The majority of the body parts were in similar anatomic positions at rest. However, variations in anatomic positions (e.g. 6% rotated head, 9% laterally bent spine), within and between embryos, were seen at 9 weeks' GA.

Conclusion

In this unique study, we showed for the first time that embryonic posture measurements at rest can be performed in a reliable way using state‐of‐the‐art four‐dimensional ultrasound and VR techniques. Already early in prenatal life there are differences regarding posture within and between embryos.

Three-dimensional reconstruction and morphologic measurements of human embryonic hearts: a new diagnostic and quantitative method applicable to fetuses younger than 13 weeks of gestation

Improvements in the diagnosis of congenital malformations explain the increasing early termination of pregnancies. Before 13 weeks of gestation, an accurate in vivo anatomic diagnosis cannot currently be made in all fetuses with current imaging instrumentation. Anatomopathologic examinations remain the gold standard to make accurate diagnoses, although they reach limits between 9 and 13 weeks of gestation. We present the first results of a methodology that can be applied routinely, using standard histologic section, thus enabling the reconstruction, visual estimate, and quantitative analysis of 13-week human embryonic cardiac structures. The cardiac blocks were fixed, embedded in paraffin, and entirely sliced by a microtome. One of 10 slices was topographically colored and digitized on an optical microscope. Cardiac volume was recovered by semiautomatic realignment of the sections. Another semiautomatic procedure allowed extracting and labeling of cardiac structures from the volume. Structures were studied with display tools, which disclosed the internal and external cardiac components and enabled determination of size, thickness, and precise positioning of ventricles, atria, and large vessels. This pilot study confirmed that a new 3-dimensional reconstruction and visualization method enables accurate diagnoses, including in embryos younger than 13 weeks. Its implementation at earlier stages of embryogenesis will provide a clearer view of cardiac development.

Exploring the impact of prior spontaneous miscarriage on stress among pregnant women during the first trimester: an observational study

BACKGROUND

Spontaneous miscarriage (SM) is the most common complication of pregnancy. Its psychological repercussions are widely documented but few studies have investigated its effect on women's experience of a subsequent pregnancy.

AIM

To evaluate the impact of prior SM on the level of stress experienced by pregnant women during the first trimester of pregnancy.

DESIGN AND SETTING

Cross-sectional, observational study, which was conducted between June and October 2021 in France.

METHOD

A self-report questionnaire was distributed to women in the first trimester of pregnancy. Stress was assessed using the Antenatal Perceived Stress Inventory to yield an overall score and a score for three dimensions ('medical and obstetric risks or fetal health'; 'psychosocial changes during pregnancy'; and the 'prospect of childbirth'). Women with a history of prior SM and those without were compared.

RESULTS

In total, 93 women were included; 63 without and 30 with a history of prior SM. Prior SM was not associated with the overall score. The score for the dimension 'medical and obstetric risks or fetal health' was significantly higher in women with prior SM (3.00±0.86 versus 2.34±0.80; β = 0.61 [95% confidence interval {CI} = 0.25 to 0.96]; P = 0.001). Prior SM was significantly associated with the items 'the baby's health' (P = 0.048) and 'the echography' (P = 0.002).

CONCLUSION

This study shows a significant impact of prior SM on the level of stress of pregnant women during the first trimester, particularly relating to the medical and obstetric risks or fetal health, underlining the need for appropriate psychological support to be provided to women who experience SM.

Adaptation of a Brazilian university hospital to clinical treatment of ectopic pregnancy: Lessons learned over 17 years

OBJECTIVE

To describe and compare the annual success rates of medical treatment in the analyzed period and to evaluate the associated factors.

METHODS

Retrospective study with 158 women with tubal pregnancy followed up over 17 years. Statistical analysis was performed using the Cochran-Armitage test, the χ2 test, Mann-Whitney test, and multiple logistic regression.

RESULTS

The success rate was 47.4%. There was a trend of significant change in the success rate of clinical treatment over time (Z = 2.01, P = 0.044); it was associated to undergoing treatment between 2012 and 2017 (P = 0.028), the absence of abdominal pain (P = 0.020), receiving a higher dose of methotrexate (P < 0.001), and less time hospitalized (P < 0.001). In the final statistical model, we observed that receiving a higher dose of methotrexate (P = 0.025, odds ratio [OR] 1.03, 95% confidence interval [CI] 1.00-1.06), having a low serum β-HCG concentration before treatment (P = 0.003, OR 0.87, 95% CI 0.79-0.95), and not having abdominal pain (P = 0.004, OR 4.26, 95% CI 1.61-11.28) were factors associated with a higher chance of successful clinical treatment for tubal pregnancy.

CONCLUSION

A greater chance of success was observed among women undergoing clinical treatment from 2012 onwards, who used higher doses of methotrexate, were asymptomatic at admission, and had low concentrations of β-hCG.

Local anaesthesia for pain control in first trimester surgical abortion

BACKGROUND

Abortions prior to 14 weeks are among the most common outpatient surgical procedures performed on people capable of becoming pregnant. Various methods have been used to control pain; however, many people still experience pain with the procedure.

OBJECTIVES

To evaluate the benefits and harms of local anaesthesia given for pain control during surgical abortion at less than 14 weeks' gestation.

SEARCH METHODS

We searched CENTRAL (Ovid EBM Reviews), MEDLINE (Ovid), Embase, POPLINE, and Google Scholar to December 2022 for randomized controlled trials of pain control in surgical abortion at less than 14 weeks' gestation using suction aspiration. We searched the reference lists of related reviews and articles.

SELECTION CRITERIA

We selected effectiveness and comparative effectiveness randomized controlled trials that studied local anaesthesia with common local anaesthetics and administration routes given for pain control in surgical abortion at less than 14 weeks' gestation using uterine aspiration. Outcomes included intraoperative pain, patient satisfaction, and adverse events.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methods. We computed mean differences (MD) with 95% confidence intervals (CI) for continuous variables reporting a mean. We assessed the certainty of evidence using GRADE.

MAIN RESULTS

Thirteen studies with 1992 participants met the inclusion criteria. Due to heterogeneity of interventions, we could not pool more than two studies for any outcome. We used 13 mm improvement on a visual/verbal analogue scale to indicate a clinically meaningful difference in pain with surgical abortion (pain with dilation, aspiration, or during procedure). Based on type of pain control, we divided studies into three groups. Paracervical block (PCB) effectiveness trials A 20 mL 1% lidocaine PCB reduced pain with dilation (MD -37.00, 95% CI -45.64 to -28.36), and aspiration (MD -26.00, 95% CI -33.48 to -18.52) compared to a sham PCB (1 RCT, 120 participants; high-certainty evidence). A PCB with 14 mL of 1% chloroprocaine resulted in a slight reduction in pain with aspiration compared to a PCB with normal saline injected at two or four sites (MD -1.50, 95% CI -2.45 to -0.55; 1 RCT, 79 participants; high-certainty evidence). PCB comparative effectiveness trials An ultracaine PCB probably results in little to no clinically meaningful difference in pain during procedure compared to topical cervical lidocaine spray (median 1 point higher, interquartile range (IQR) 0 to 3; P < 0.001; 1 RCT, 48 participants; moderate-certainty evidence). A 1000 mg dose of intravenous paracetamol probably does not decrease pain as much as ultracaine PCB during procedure (median 2 points higher, IQR 1 to 3; P < 0.001; 1 RCT, 46 participants; moderate-certainty evidence). Various local anaesthetics in PCB comparative effectiveness trials A 10 mL buffered 2% lidocaine PCB probably does not result in a clinically meaningful difference in pain with dilation compared to a plain lidocaine PCB (MD -0.80, 95% CI -0.89 to -0.71; 1 RCT, 167 participants; moderate-certainty evidence). A buffered lidocaine PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to plain lidocaine PCB (MD -0.57, 95% CI -1.01 to -0.06; 2 RCTs, 291 participants; moderate-certainty evidence). Non-PCB local anaesthesia or PCB technique effectiveness trials PCB: waiting versus no waiting Waiting three to five minutes between 1% lidocaine PCB injection and dilation probably does not result in a clinically meaningful difference in pain with dilation compared to not waiting (MD -0.70, 95% CI -1.23 to -0.17; 2 RCTs, 357 participants; moderate-certainty evidence). Topical cervical analgesia Topical 10 mL 2% lignocaine gel probably does not result in a clinically meaningful difference in pain with aspiration compared to KY Jelly (MD -0.87, 95% CI -1.60 to -0.14; 1 RCT, 131 participants; moderate-certainty evidence). In participants who also received a PCB, 20 mg topical cervical lidocaine spray probably does not result in a clinically meaningful difference in pain during the procedure compared to two pumps of normal saline spray (median -1 point, IQR -2 to -1; P < 0.001; 1 RCT, 55 participants; moderate-certainty evidence). Intravenous paracetamol 1000 mg compared to two pumps of cervical lidocaine spray probably does not results in a clinically meaningful difference in pain procedure (median 1 point, IQR -2 to 2; P < 0.001; 1 RCT, 48 participants; low-certainty evidence). Non-PCB local anaesthesia or PCB technique comparative effectiveness trials Depth of PCB The evidence suggests that a 3-cm deep PCB probably does not result in a clinically meaningful difference in pain with aspiration compared to a 1.5-cm deep PCB (MD -1.00, 95% CI -1.09 to -0.91; 2 RCTs, 229 participants; low-certainty evidence). PCB: four sites versus two sites A two-site (4-8 o'clock) 20 mL 1% lidocaine PCB does not result in a clinically meaningful difference in pain with dilation compared to a four-site (2-4-8-10 o'clock) PCB (MD 8.60, 95% CI 0.69 to 16.51; 1 RCT, 163 participants; high-certainty evidence). Overall, participants reported moderately high satisfaction with pain control and studies reported few adverse events.

AUTHORS' CONCLUSIONS

Evidence from this updated review indicates that a 20 mL 1% plain lidocaine PCB decreases pain during an abortion procedure. Evidence supports forgoing buffering lidocaine and a wait time between PCB injection and cervical dilation. A 1.5-cm deep injection as opposed to a 3-cm deep injection is sufficient. A two-site PCB injection as opposed to a four-site injection has similar effectiveness. Topical cervical anaesthesia (10 mL 2% lignocaine gel or 20 mg topical cervical lidocaine spray) as compared to placebo did not decrease pain based on moderate-certainty evidence, but then when compared to PCB, pain control was similar. Due to this inconsistency in evidence regarding the effectiveness of topical anaesthesia, its routine use is presently not supported. This review did not include studies of pain management with conscious sedation but, based on the results of our prior Cochrane review and the 2022 WHO guidelines, we recommend that the option of combination of pain management using conscious sedation plus PCB and non-steroidal anti-inflammatory drugs should be offered where conscious sedation is available as it further decreases pain.

Very Prolonged Anti-D: Confusion Surrounding Alloimmunization After Extra Rh Immunoglobulin: A Case Report

BACKGROUND

Rh immunoglobulin (RhIg) is usually detectable a maximum of 12 to 14 weeks after administration. Positive antibodies beyond this time frame suggests alloimmunization.

CASE

A woman had three pregnancies over a 6-month period, with two first-trimester losses. She received RhIg in the first pregnancy but not in the second. Two months after the second loss, in her third pregnancy, she received RhIg at week 6 due to first-trimester bleeding. She was subsequently anti-D antibody positive up to week 28 with antibodies too low to titre, leading to confusion about whether alloimmunization had occurred.

CONCLUSION

Rh Ig administration led to positive anti-D antibodies lasting 22 weeks, suggesting keeping this differential diagnosis in mind when suspecting alloimmunization with positive antibodies at levels too low to titre.

Diagnostic accuracy of ultrasound screening for fetal structural abnormalities during the first and second trimester of pregnancy in low-risk and unselected populations

BACKGROUND

Prenatal ultrasound is widely used to screen for structural anomalies before birth. While this is traditionally done in the second trimester, there is an increasing use of first-trimester ultrasound for early detection of lethal and certain severe structural anomalies.

OBJECTIVES

To evaluate the diagnostic accuracy of ultrasound in detecting fetal structural anomalies before 14 and 24 weeks' gestation in low-risk and unselected pregnant women and to compare the current two main prenatal screening approaches: a single second-trimester scan (single-stage screening) and a first- and second-trimester scan combined (two-stage screening) in terms of anomaly detection before 24 weeks' gestation.

SEARCH METHODS

We searched MEDLINE, EMBASE, Science Citation Index Expanded (Web of Science), Social Sciences Citation Index (Web of Science), Arts & Humanities Citation Index and Emerging Sources Citation Index (Web of Science) from 1 January 1997 to 22 July 2022. We limited our search to studies published after 1997 and excluded animal studies, reviews and case reports. No further restrictions were applied. We also screened reference lists and citing articles of each of the included studies.

SELECTION CRITERIA

Studies were eligible if they included low-risk or unselected pregnant women undergoing a first- and/or second-trimester fetal anomaly scan, conducted at 11 to 14 or 18 to 24 weeks' gestation, respectively. The reference standard was detection of anomalies at birth or postmortem.

DATA COLLECTION AND ANALYSIS

Two review authors independently undertook study selection, quality assessment (QUADAS-2), data extraction and evaluation of the certainty of evidence (GRADE approach). We used univariate random-effects logistic regression models for the meta-analysis of sensitivity and specificity.

MAIN RESULTS

Eighty-seven studies covering 7,057,859 fetuses (including 25,202 with structural anomalies) were included. No study was deemed low risk across all QUADAS-2 domains. Main methodological concerns included risk of bias in the reference standard domain and risk of partial verification. Applicability concerns were common in studies evaluating first-trimester scans and two-stage screening in terms of patient selection due to frequent recruitment from single tertiary centres without exclusion of referrals. We reported ultrasound accuracy for fetal structural anomalies overall, by severity, affected organ system and for 46 specific anomalies. Detection rates varied widely across categories, with the highest estimates of sensitivity for thoracic and abdominal wall anomalies and the lowest for gastrointestinal anomalies across all tests. The summary sensitivity of a first-trimester scan was 37.5% for detection of structural anomalies overall (95% confidence interval (CI) 31.1 to 44.3; low-certainty evidence) and 91.3% for lethal anomalies (95% CI 83.9 to 95.5; moderate-certainty evidence), with an overall specificity of 99.9% (95% CI 99.9 to 100; low-certainty evidence). Two-stage screening had a combined sensitivity of 83.8% (95% CI 74.7 to 90.1; low-certainty evidence), while single-stage screening had a sensitivity of 50.5% (95% CI 38.5 to 62.4; very low-certainty evidence). The specificity of two-stage screening was 99.9% (95% CI 99.7 to 100; low-certainty evidence) and for single-stage screening, it was 99.8% (95% CI 99.2 to 100; moderate-certainty evidence). Indirect comparisons suggested superiority of two-stage screening across all analyses regarding sensitivity, with no significant difference in specificity. However, the certainty of the evidence is very low due to the absence of direct comparisons.

AUTHORS' CONCLUSIONS

A first-trimester scan has the potential to detect lethal and certain severe anomalies with high accuracy before 14 weeks' gestation, despite its limited overall sensitivity. Conversely, two-stage screening shows high accuracy in detecting most fetal structural anomalies before 24 weeks' gestation with high sensitivity and specificity. In a hypothetical cohort of 100,000 fetuses, the first-trimester scan is expected to correctly identify 113 out of 124 fetuses with lethal anomalies (91.3%) and 665 out of 1776 fetuses with any anomaly (37.5%). However, 79 false-positive diagnoses are anticipated among 98,224 fetuses (0.08%). Two-stage screening is expected to correctly identify 1448 out of 1776 cases of structural anomalies overall (83.8%), with 118 false positives (0.1%). In contrast, single-stage screening is expected to correctly identify 896 out of 1776 cases before 24 weeks' gestation (50.5%), with 205 false-positive diagnoses (0.2%). This represents a difference of 592 fewer correct identifications and 88 more false positives compared to two-stage screening. However, it is crucial to acknowledge the uncertainty surrounding the additional benefits of two-stage versus single-stage screening, as there are no studies directly comparing them. Moreover, the evidence supporting the accuracy of first-trimester ultrasound and two-stage screening approaches primarily originates from studies conducted in single tertiary care facilities, which restricts the generalisability of the results of this meta-analysis to the broader population.

Evaluation of first- and third-trimester afamin levels in preeclampsia

OBJECTIVE

The aim of this study was to investigate serum afamin levels in the first and third trimesters in preeclampsia.

METHODS

Serum samples from 118 patients in the first and third trimesters were analyzed. Serum samples were collected from pregnant women who had enrolled in the first trimester. Blood was then collected from pregnant women who had developed preeclampsia and from healthy controls in the third trimester. The collected blood samples were resolved for analysis, and serum afamin concentrations were measured in the first and third trimesters. Preeclampsia and healthy controls were compared.

RESULTS

There was no significant difference between the control and preeclampsia groups in terms of age, body mass index, and smoking. Afamin levels in the first and third trimesters were higher in the preeclampsia group than in the control group (p<0.05). In the subgroup analysis of the preeclampsia group, afamin levels were higher in the early-onset preeclampsia group than in the late-onset preeclampsia group in the first and third trimesters (p<0.05). In the receiver operating characteristic analysis afamin levels were 96.23 ng/mL in the first trimester and 123.57 ng/mL in the third trimester as cut-off values for preeclampsia.

CONCLUSION

Serum afamin levels are useful for predicting preeclampsia in the first trimester in pregnant women and can be used in clinical practice as a supportive biomarker for the diagnosis of preeclampsia in the third trimester. Meta-analyzes are needed to investigate the effect of afamin levels in the prediction and diagnosis of preeclampsia and to determine the cut-off value.