P-748 Cesarean scar defect does not predict embryo transfer outcomes: A retrospective cohort study

Study question

Is the presence of a cesarean scar defect associated with live birth outcomes at the time of embryo transfer?

Summary answer

The presence of a cesarean scar defect is not predictive of live birth rates at the time of embryo transfer.

What is known already

Cesarean delivery is associated with subsequent impaired fertility, with lower pregnancy and live birth rates and longer inter-pregnancy intervals, compared to patients who delivered vaginally. Studies exploring pregnancy rates after IVF and embryo transfer also suggest lower pregnancy rates among patients with prior cesarean delivery. A postulated mechanism by which a prior cesarean delivery may impact fertility is the cesarean scar defect, and prior studies have shown a possible association between a scar defect and suboptimal outcomes.

Study design, size, duration

We retrospectively identified a patient cohort based out of the Ottawa Fertility Centre in Ottawa, Ontario, Canada, between 2013 and 2019.

Participants/materials, setting, methods

This retrospective cohort study included 317 patients with a prior cesarean delivery. Embryo transfer outcomes compared between the two groups based on the finding of a cesarean scar defect. The primary outcome was live birth rate, secondary outcomes of positive hCG, clinical intrauterine pregnancy, miscarriage rate. We fit a multivariate log binomial regression model with a priori variables for the primary and secondary outcomes, adjusting for patient and cycle characteristics.

Main results and the role of chance

There was no statistically significant difference in live birth rate among patients with a cesarean scar defect compared to those without, 28.0% vs 29.5% respectively (adjusted RR 0.95, 95% CI 0.68-1.35). There was no statistically significant difference in any of the secondary outcomes. Area of the defect and subgroup analysis of fresh vs frozen embryo transfer did not demonstrate any difference. Secondary analysis of patients with retroverted uterus had significantly lower live birth rates compared to those with an anteverted uterus, 17.7% vs 32.4%, respectively (adjusted RR 0.56, 95% CI 0.34-0.91).

Limitations, reasons for caution

Although a multivariate log binomial model was used to adjust for clinically relevant confounders, there remains the possibility for residual confounding given the observational nature of our study.

Wider implications of the findings

The results of our study suggest that, after adjusting for patient and cycle characteristics, the presence of a cesarean scar defect may not impact live birth outcomes and secondary analysis of the impact of uterine retroversion requires more study.

Trial registration number

Not applicable

The Canadian Assisted Reproductive Technologies Register (CARTR) Plus database: a validation study

STUDY QUESTION

Are data accurately documented in the Canadian Assisted Reproductive Technologies Register (CARTR) Plus database?

SUMMARY ANSWER

Measures of validity were strong for the majority of variables evaluated while those with moderate agreement were FSH levels, oocyte origin and elective single embryo transfer.

WHAT IS KNOWN ALREADY

Health databases and registries are excellent sources of data. However, as these databases are typically not established for the primary purpose of performing research, they should be evaluated prior to utilization for research both to inform the study design and to determine the extent to which key study variables, such as patient characteristics or therapies provided, are accurately documented in the database. CARTR Plus is Canada's national register for collecting extensive information on IVF and corresponding pregnancy outcomes, and it has yet to be validated.

STUDY DESIGN SIZE DURATION

This study evaluating the data translation CARTR Plus database examined IVF cycles performed in 2015 using data directly from patient charts. Six clinics across Canada were recruited to participate, using a purposive sampling strategy. Fixed random sampling was employed to select 146 patient cycles at each clinic, representing unique patients. Only a single treatment cycle record from a unique patient at each clinic was considered during chart selection.

PARTICIPANTS/MATERIALS SETTING METHODS

Twenty-five data elements (patient characteristics, treatments and outcomes) were reabstracted from patient charts, which were declared the reference standard. Data were reabstracted by two independent auditors with relevant clinical knowledge after confirming inter-rater reliability. These data elements from the chart were then compared to those in CARTR Plus. To determine the validity of these variables, we calculated kappa coefficients, sensitivity, specificity, positive predictive value and negative predictive value with 95% CI for categorical variables and calculated median differences and intraclass correlation coefficients (ICC) for continuous variables.

MAIN RESULTS AND THE ROLE OF CHANCE

Six clinics agreed to participate in this study representing five Canadian provinces. The mean age of patients was 35.5 years, which was similar between the two data sources, resulting in a near perfect level of agreement (ICC = 0.99; 95% CI: 0.99, 0.99). The agreement for FSH was moderate, ICC = 0.68 (95% CI: 0.64, 0.72). There was nearly perfect agreement for cycle type, kappa = 0.99 (95% CI: 0.98, 1.00). Over 90% of the cycles in the reabstracted charts used autologous oocytes; however, data on oocyte source were missing for 13% of cycles in CARTR Plus, resulting in a moderate degree of agreement, kappa = 0.45 (95% CI, 0.37, 0.52). Embryo transfer and number of embryos transferred had nearly perfect agreement, with kappa coefficients greater than 0.90, whereas that for elective single or double embryo transfer was much lower (kappa = 0.55; 95% CI: 0.49, 0.61). Agreement was nearly perfect for pregnancy type, and number of fetal sacs and fetal hearts on ultrasound, all with kappa coefficients greater than 0.90.

LARGE-SCALE DATA

N/A.

LIMITATIONS REASONS FOR CAUTION

CARTR Plus contains over 200 variables, of which only 25 were assessed in this study. This foundational validation work should be extended to other CARTR Plus database variables in future studies.

WIDER IMPLICATIONS OF THE FINDINGS

This study provides the first assessment of the quality of the data translation process of the CARTR Plus database, and we found very high quality for the majority of the variables that were analyzed. We identified key data points that are either too often lacking or inconsistent with chart data, indicating that changes in the data entry process may be required.

STUDY FUNDING/COMPETING INTERESTS

This study was funded by Canadian Institutes of Health Research (CIHR) (Grant Number FDN-148438) and by the Canadian Fertility and Andrology Society Research Seed Grant (Grant Number: N/A). The authors report no conflict of interest.

TRIAL REGISTRATION NUMBER

Not applicable.

A systematic review of database validation studies among fertility populations

STUDY QUESTION

Are routinely collected data from fertility populations adequately validated?

SUMMARY ANSWER

Of the 19 studies included, only one validated a national fertility registry and none reported their results in accordance with recommended reporting guidelines for validation studies.

WHAT IS KNOWN ALREADY

Routinely collected data, including administrative databases and registries, are excellent sources of data, particularly for reporting, quality assurance, and research. However, these data are subject to misclassification bias due to misdiagnosis or errors in data entry and therefore need to be validated prior to using for clinical or research purposes.

STUDY DESIGN SIZE DURATION

We conducted a systematic review by searching Medline, Embase, and CINAHL from inception to 6 October 2016 to identify validation studies of databases that contain routinely collected data in an ART setting. Webpages of international ART centers were also searched.

PARTICIPANTS/MATERIALS SETTING METHODS

We included studies that compared at least two data sources to validate ART population data. Key words and MeSH terms were adapted from previous systematic reviews investigating routinely collected data (e.g. administrative databases and registries), measures of validity (including sensitivity, specificity, and predictive value), and ART (including infertility, IVF, advanced reproductive age, and diminished ovarian reserve). Only full-text studies in English were considered. Results were synthesized qualitatively. The electronic search yielded 1074 citations, of which 19 met the inclusion criteria.

MAIN RESULTS AND THE ROLE OF CHANCE

Two studies validated a fertility database using medical records; seven studies used an IVF registry to validate vital records or maternal questionnaires, and two studies failed to adequately describe their reference standard. Four studies investigated the validity of mode of conception from birth registries; two studies validated diagnoses or treatments in a fertility database; four studies validated a linkage algorithm between a fertility registry and another administrative database; one study created an algorithm in a single database to identify a patient population. Sensitivity was the most commonly reported measure of validity (12 studies), followed by specificity (9 studies). Only three studies reported four or more measures of validation, and five studies presented CIs for their estimates. The prevalence of the variable in the target population (pre-test prevalence) was reported in seven studies; however, only four of the studies had prevalence estimates from the study population (post-test prevalence) within a 2% range of the pre-test estimate. The post-test estimate was largely discrepant from the pre-test value in two studies.

LIMITATIONS REASONS FOR CAUTION

The search strategy was limited to the studies and reports published in English, which may not capture validation studies from countries that do not speak English. Furthermore, only three specific fertility-based diagnostic variables (advanced reproductive age, diminished ovarian reserve, and chorionicity) were searched in Medline, Embase, and CINAHL. Consequently, published studies with other diagnoses or conditions relevant to infertility may not have been captured in our review.

WIDER IMPLICATIONS OF THE FINDINGS

There is a paucity of literature on validation of routinely collected data from a fertility population. Furthermore, the prevalence of the markers that have been validated are not being presented, which can lead to biased estimates. Stakeholders rely on these data for monitoring outcomes of treatments and adverse events; therefore, it is essential to ascertain the accuracy of these databases and make the reports publicly available.

STUDY FUNDING/COMPETING INTERESTS

This study was supported by Canadian Institutes of Health Research (CIHR) (FDN-148438). There are no competing interests for any of the authors.

REGISTRATION NUMBER

International Prospective Register of Systematic Reviews ID: CRD42016048466.

Endometriosis and adverse maternal, fetal and neonatal outcomes, a systematic review and meta-analysis

STUDY QUESTION

How is endometriosis associated with adverse maternal, fetal and neonatal outcomes of pregnancy?

SUMMARY ANSWER

Women with endometriosis are at elevated risk for serious and important adverse maternal (pre-eclampsia, gestational diabetes, placenta praevia and Cesarean section) and fetal or neonatal outcomes (preterm birth, PPROM, small for gestational age, stillbirth and neonatal death).

WHAT IS KNOWN ALREADY

A number of studies have shown an association between endometriosis and certain adverse maternal and fetal outcomes, but the results have been conflicting with potential for confounding by the use of assisted reproductive technology.

STUDY DESIGN, SIZE, DURATION

A systematic review and meta-analysis of observational studies (1 January 1990-31 December 2017) that evaluated the effect of endometriosis on maternal, fetal and neonatal outcomes was conducted.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Studies were considered for inclusion if they were prospective or retrospective cohort or case-control studies; included women greater than 20 weeks gestational age with endometriosis; included a control group of gravid women without endometriosis; and, reported at least one of the outcomes of interest. Each study was reviewed for inclusion, data were extracted and risk of bias was assessed by two independent reviewers.

MAIN RESULTS AND THE ROLE OF CHANCE

The search strategy identified 33 studies (sample size, n = 3 280 488) for inclusion. Compared with women without endometriosis, women with endometriosis had higher odds of pre-eclampsia (odds ratio [OR] = 1.18 [1.01-1.39]), gestational hypertension and/or pre-eclampsia (OR = 1.21 [1.05-1.39]), gestational diabetes (OR = 1.26 [1.03-1.55]), gestational cholestasis (OR = 4.87 [1.85-12.83]), placenta praevia (OR = 3.31 [2.37, 4.63]), antepartum hemorrhage (OR = 1.69 [1.38-2.07]), antepartum hospital admissions (OR = 3.18 [2.60-3.87]), malpresentation (OR = 1.71 [1.34, 2.18]), labor dystocia (OR = 1.45 [1.04-2.01]) and cesarean section (OR = 1.86 [1.51-2.29]). Fetuses and neonates of women with endometriosis were also more likely to have preterm premature rupture of membranes (OR = 2.33 [1.39-3.90]), preterm birth (OR = 1.70 [1.40-2.06]), small for gestational age <10th% (OR = 1.28 [1.11-1.49]), NICU admission (OR = 1.39 [1.08-1.78]), stillbirth (OR = 1.29 [1.10, 1.52]) and neonatal death (MOR = 1.78 [1.46-2.16]). Among the subgroup of women who conceived spontaneously, endometriosis was found to be associated with placenta praevia, cesarean section, preterm birth and low birth weight. Among the subgroup of women who conceived with the use of assisted reproductive technology, endometriosis was found to be associated with placenta praevia and preterm birth.

LIMITATIONS, REASONS FOR CAUTION

As with any systematic review, the review is limited by the quality of the included studies. The diagnosis for endometriosis and the selection of comparison groups were not uniform across studies. However, the effect of potential misclassification would be bias towards the null hypothesis.

WIDER IMPLICATIONS OF THE FINDINGS

The association between endometriosis with the important and serious pregnancy outcomes observed in our meta-analysis, in particular stillbirth and neonatal death, is concerning and warrants further studies to elucidate the mechanisms for the observed findings.

STUDY FUNDING/COMPETING INTEREST(S)

Dr Shifana Lalani is supported by a Physicians' Services Incorporated Foundation Research Grant, and Dr Innie Chen is supported by a University of Ottawa Clinical Research Chair in Reproductive Population Health and Health Services. Dr Singh declares conflicts of interests with Bayer, Abvie, Allergan and Cooper Surgical. All other authors have no conflicts of interests to declare.

REGISTRATION NUMBER

PROSPERO CRD42015013911.