Role of chromosome abnormalities in ectopic pregnancy

An Endometrial Thickness < 8 mm Was Associated With a Significantly Increased Risk of EP After Freeze-Thaw Transfer: An Analysis of 5,960 Pregnancy Cycles

INTRODUCTION

Endometrium characteristics that are most likely to induce ectopic pregnancy were investigated on the basis of the data of 5,960 pregnant freeze-thaw cycles.

METHODS

A total of 5,960 pregnancy cycles after freeze-thaw embryos transfer were included, with the number of intrauterine and ectopic pregnancies being 5,777 and 183, respectively. Ectopic pregnancy was the primary outcome. Endometrial thickness was the main measured variable. The risk factors of ectopic pregnancy were eventually determined based on univariate analysis and subsequent multiple-stepwise logistic regression analysis.

RESULTS

1. After adjusting for confounders, endometrial thickness could independently predict ectopic pregnancy. The adjusted odd ratios for women with endometrial thickness in the ranges of < 8 mm, 8-9.9 mm, and 10-11.9 mm were 3.270 [95% confidence interval (CI), 1.113-9.605, P = 0.031], 2.758 (95% CI, 0.987-7.707, P = 0.053), and 1.456 (95% CI, 0.502-4.225, P = 0.489), respectively, when compared with those having an endometrial thickness of 12-13.9 mm. 2. Endometrial type and preparation protocol were however not identified as risk factors for ectopic pregnancy.

DISCUSSION

1. After freeze-thaw embryo transfer, risks of ectopic pregnancy were significantly higher when the endometrial thickness was < 8 mm. 2. A thin endometrial thickness could be linked with abnormal endometrial peristaltic waves or abnormal endometrial receptivity. 3. Adequate attention should therefore be paid to patients with a thin endometrial thickness to prevent EP or to achieve early diagnosis during the peri-transplantation period.

Novel ploidy analysis in ectopic pregnancy

Objective

To study whether a single-nucleotide polymorphism (SNP) array could be used to test tissue from ectopic pregnancy to distinguish whether ectopic pregnancies were aneuploid.

Design

Case series report.

Setting

Academic medical center.

Patients

One hundred seventy-eight women who underwent surgery for ectopic pregnancy at Northwestern Memorial Hospital between 2015 and 2018 were eligible for participation; written consent was obtained from 33 patients. Eight subjects had sufficient DNA samples and were included in the analysis. Maternal and paternal DNA samples were self-collected by buccal swab. Archived paraffin tissue containing chorionic villi from each surgically removed ectopic specimen was analyzed using SNP microarray technology to determine chromosome number and evaluate for maternal cell contamination.

Interventions

None.

Main Outcome Measures

Prevalence of aneuploidy in ectopic pregnancy specimens as well as success of SNP array technology in formalin-fixed and paraffin-embedded specimens.

Results

Subjects had a mean (±SD) age of 33.4 ± 5.4 years, body mass index of 23.4 ± 5.7 kg/m², 3.3 ± 1.8 prior pregnancies, and 1.5 ± 1.4 live births. Genetic testing revealed that all eight tested samples were euploid, 6 female and 2 male (two arr(1-22)x2, (X,Y)x1 and 6 arr(1-22, X)x2); maternal cell contamination was ruled out in all cases.

Conclusions

This study showed proof of concept for the use of routinely stored formalin-fixed, paraffin-embedded tissue blocks with DNA extraction for SNP array to detect ploidy status of ectopic pregnancy. Although all tested samples were euploid, further research is needed to gain a definitive answer to this question and better understand the mechanism that leads to ectopic implantation.

Demographic, lifestyle, and reproductive risk factors for ectopic pregnancy

OBJECTIVE

To evaluate the relationship between demographic, lifestyle, and reproductive factors and the risk of ectopic pregnancy (EP).

DESIGN

Prospective cohort.

SETTING

United States.

PATIENT(S)

Nurses' Health Study II cohort comprising 41,440 pregnancies from 22,356 women.

INTERVENTION(S)

Demographic, lifestyle, and reproductive factors self-reported in 1989 then updated every 2 years. Multivariable log-binomial regression models with generalized estimating equations were used to estimate adjusted risk ratios (aRR).

MAIN OUTCOME MEASURE(S)

Ectopic pregnancy.

RESULT(S)

Incident EP was reported in 411 (1.0%) pregnancies. Former and current smokers had 1.22 (95% confidence interval [CI], 0.97-1.55) and 1.73 (95% CI, 1.28-2.32) times, respectively, the risk of EP compared with never smokers. The risk of EP 10 years after quitting was similar to never smokers (aRR 0.90; 95% CI, 0.60-1.33). Women consuming ≥10 g/day of alcohol had 1.50 (95% CI, 1.08-2.09) times the risk of EP compared with never consumers. In utero exposure to diethylstilbestrol (aRR 3.55; 95% CI, 2.51-5.01), earlier initiation of oral contraceptives (aRR 2.64; 95% CI, 1.70-4.09 for <16 years vs. never), intrauterine device use (aRR 3.99; 95% CI, 2.06-7.72), or history of infertility (aRR 3.03; 95% CI, 2.48-3.71) or tubal ligation (aRR 16.27; 95% CI, 11.76-22.53) also were associated with a higher risk of EP.

CONCLUSION(S)

Women who were current or former smokers, consumed ≥10 g/day of alcohol, were exposed to diethylstilbestrol in utero, initiated oral contraceptives at earlier than age 16 years (which may be a marker of riskier sexual behaviors), and who had a history of infertility, intrauterine device use, or tubal ligation had a higher risk of EP.

Ectopic pregnancy: diagnosis and management

The incidence of ectopic pregnancies is increasing, which may be related to better diagnostic tools as well as the increasing use of assisted reproductive technologies. However, the signs and symptoms of ectopic pregnancy can be similar to other complications of early pregnancy such as miscarriage. Diagnosis often requires serial human chorionic gonadotropin levels along with ultrasound and, in some cases, dilation and curettage. Once a diagnosis has been made, treatment options include medical therapy with methotrexate and surgery, which can often be performed via the laparoscope. Fertility rates after therapy are similar for both medically and surgically treated patients.

Suspected Ectopic Pregnancy

Women who present with pain and bleeding in the first trimester are at risk for ectopic pregnancy, a life-threatening condition. Conditions that predispose a woman to ectopic pregnancy are damaged fallopian tubes from prior tubal surgery or previous pelvic infection, smoking, and conception using assisted reproduction. Many women without risk factors can develop an ectopic pregnancy. A diagnostic algorithm that includes the use of transvaginal ultrasonography, human chorionic gonadotropin (hCG) concentrations, and, sometimes, uterine curettage can definitively diagnose women at risk in a timely manner. The absence of an intrauterine pregnancy above an established cut point of hCG is consistent with an abnormal pregnancy but does not distinguish a miscarriage from an ectopic pregnancy. When the initial hCG value is low, serial hCG values can be used to determine whether a gestation is potentially viable or spontaneously resolving. The minimal rise in hCG for a viable pregnancy is 53% in 2 days. The minimal decline of a spontaneous abortion is 21-35% in 2 days, depending on the initial level. A rise or fall in serial hCG values that is slower than this is suggestive of an ectopic pregnancy. Women diagnosed with an unruptured ectopic pregnancy are potential candidates for medical management with methotrexate. Intramuscular injection with methotrexate can be used to safely treat an ectopic pregnancy with success rates, tubal patency rates, and future fertility that are similar to those obtained with conservative surgery. Success rates using methotrexate are inversely rated to baseline hCG values and are higher using "multidose" compared with "single-dose" regimens. Surgical treatment may be conservative or definitive and should be attempted in most cases via laparoscopy.

Detection of chromosome abnormalities by quantitative fluorescent PCR in ectopic pregnancies

OBJECTIVE

To evaluate the potential value of quantitative fluorescent polymerase chain reaction (QF-PCR) in the detection of chromosome abnormalities in ectopic pregnancies.

METHODS

Seventy chorionic villi samples of ectopic pregnancies were studied by QF-PCR. Primers for chromosomes 16, 21, X and Y in chorionic villi were evaluated. Fluorescence in situ hybridization (FISH) was performed when results of QF-PCR showed aneuploidy, in case of unexplicable QF-PCR peaks, and in 10 cases with normal QF-PCR results.

RESULTS

QF-PCR produced a result for chromosomes X and Y in 66 cases (94%), for chromosome 16 in 62 cases (89%) and for chromosome 21 in 55 cases (79%). Overall, QF-PCR produced a result for the chromosomes tested in 54 ectopic pregnancy cases (77%). Fifty-two of these results were normal disomic (96%) and two were abnormal, one trisomy 16 (2%) and one triploidy (2%). In 16 cases (23%) no definite QF-PCR results could be obtained for all chromosomes, 11 due to amplification failure, and 5 due to unexplicable QF-PCR peaks. In 10 cases with normal QF-PCR results, disomy was confirmed by FISH. The trisomy 16 was also confirmed by FISH. Furthermore, a result was obtained with FISH in 5 of the cases without definite QF-PCR results.

CONCLUSION

Although QF-PCR can establish the chromosomal status in ectopic pregnancies for chromosomes 16, 21, X and Y in the majority of cases, the technical failure rate is still considerable and does not improve results when compared to cytogenetic techniques.

Ectopic pregnancies after infertility treatment: modern diagnosis and therapeutic strategy

Ectopic pregnancy (EP) is a major event in a woman's reproductive life. It complicates infertility treatment and must be recognized early to simplify the treatment strategy, which must always be directed towards optimizing subsequent fertility. Epidemiological findings indicate that tubal history and smoking are the principal risk factors of those EP that are considered reproductive (rather than contraceptive) failures. Adding together the attributable risks for EP allows the construction of a risk scale to determine its probability for any given patient. This risk calculation makes it easier to establish a diagnostic strategy that uses abdominal and transvaginal ultrasound and hCG assays. Progesterone assays are useful only for determining the activity of the pregnancy but do not help to identify its site. Conservative treatment is to be preferred unless the EP occurs on a known hydrosalpinx. All the treatment trials and the Cochrane database meta-analysis show that medical treatment with methotrexate, preferably multidose, is equivalent in efficacy to conservative treatment with laparoscopy in the populations studied. Heterotopic pregnancies, which occur most often after assisted reproduction technology (1-3%), should preferably be treated by salpingectomy except in interstitial sites. There is no consensus that IVF is indicated after EP. The patient's age is probably the determining factor: fertility treatment should not be delayed to an age where the results would be altered, especially with the risk of a recurrent EP.