Scholarly article on topic 'The impact of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles'

The impact of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles Academic research paper on "Veterinary science"

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Abstract of research paper on Veterinary science, author of scientific article — Maged Al Mohammady, Ghada Abdel Fattah, Mostafa Mahmoud

Abstract Objective To evaluate the effect of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles. Study design Prospective cohort clinical study. Patients One hundred infertile women attending the Egyptian International Fertility/IVF center in Egypt for performing ICSI. Methods The long protocol of controlled ovarian hyperstimulation was used. Endometrial thickness and pattern were recorded on the day of HCG administration. In the combined analysis, endometrial thickness groups (4–6.9mm, 7–9.9mm, 10–12.9mm and 13–15mm) were subdivided into 3 endometrial patterns (trilaminar, intermediate and echogenic). Clinical pregnancy rate (CPR) was calculated in different groups. Results Overall CPR was 62%. Endometrial thickness of 10–12.9mm showed, however non-significantly, higher CPR in comparison with other thickness groups (73.91% versus 0% for the 4–6.9mm group, 43.75% for the 7–9.9mm group and 61.76% for the 13–15mm group, p: 0.115). Trilaminar pattern showed the highest incidence of pregnancy compared to the other patterns with a non-significantly statistical difference (69% versus 50% and 38.4%, p: 0.06). Analyzing CPR with different endometrial patterns in each endometrial thickness group revealed that trilaminar pattern with an endometrial thickness of 10–12.9mm gives significantly higher CPR in comparison with other groups (56.5%, p: 0.043). Conclusion Endometrial thickness of 10–12.9mm with trilaminar pattern is associated with higher CPR with ICSI cycles.

Academic research paper on topic "The impact of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles"

Middle East Fertility Society Journal (2013) 18, 165-170

Middle East Fertility Society Middle East Fertility Society Journal

www.mefsjournal.org www.sciencedirect.com

ORIGINAL ARTICLE

The impact of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles

Maged Al Mohammady, Ghada Abdel Fattah *, Mostafa Mahmoud

Obstetrics and Gynecology Department, Faculty of Medicine, Cairo University, Giza, Egypt

Received 27 December 2012; accepted 9 April 2013 Available online 27 June 2013

Abstract Objective: To evaluate the effect of combined endometrial thickness and pattern on the success of intracytoplasmic sperm injection (ICSI) cycles.

Study design: Prospective cohort clinical study.

Patients: One hundred infertile women attending the Egyptian International Fertility/IVF center in Egypt for performing ICSI.

Methods: The long protocol of controlled ovarian hyperstimulation was used. Endometrial thickness and pattern were recorded on the day of HCG administration. In the combined analysis, endometrial thickness groups (4-6.9 mm, 7-9.9 mm, 10-12.9 mm and 13-15 mm) were subdivided into 3 endometrial patterns (trilaminar, intermediate and echogenic). Clinical pregnancy rate (CPR) was calculated in different groups.

Results: Overall CPR was 62%. Endometrial thickness of 10-12.9 mm showed, however non-significantly, higher CPR in comparison with other thickness groups (73.91% versus 0% for the 4-6.9 mm group, 43.75% for the 7-9.9 mm group and 61.76% for the 13-15 mm group, p: 0.115). Trilaminar pattern showed the highest incidence of pregnancy compared to the other patterns with a non-significantly statistical difference (69% versus 50% and 38.4%, p: 0.06). Analyzing CPR with different endometrial patterns in each endometrial thickness group revealed that trilaminar pattern with an endometrial thickness of 10-12.9 mm gives significantly higher CPR in comparison with other groups (56.5%, p: 0.043).

Conclusion: Endometrial thickness of 10-12.9 mm with trilaminar pattern is associated with higher CPR with ICSI cycles.

© 2013 Production and hosting by Elsevier B.V. on behalf of Middle East Fertility Society.

1. Introduction

The high cost and relatively low implantation and pregnancy rates (PRs) in in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) treatment cycles have led to a need to evaluate the predictors of success in these patients. One of

1110-5690 © 2013 Production and hosting by Elsevier B.V. on behalf of Middle East Fertility Society. http://dx.doi.org/10.1016/j.mefs.2013.04.003

KEYWORDS

Endometrial thickness; Endometrial pattern; ICSI

* Corresponding author. Tel.: +20 1006513305.

E-mail addresses: ghadaabdelfatah2007@yahoo.com, m.a.youssef@

amc.uva.nl (G. Abdel Fattah).

Peer review under responsibility of Middle East Fertility Society.

Production and hosting by Elsevier

the important factors is the endometrial receptivity. Endometrial thickness has been utilized as an indirect indicator for endometrial receptivity (1).

Following the periodic stimulation of ovarian hormones, the changes in endometrial structure during the menstrual cycle can be identified easily by ultrasound examination (2).

The effect of endometrial thickness on pregnancy rates in assisted reproductive technology (ART) patients has been evaluated by many authors (3-11) but results are controversial.

Some authors demonstrated a higher pregnancy rate at certain endometrial thickness (3-7), while others did not show a significant correlation between endometrial thickness and pregnancy rates in IVF/ICSI patients (8-11).

A no triple-line endometrial pattern seems to be a prognostic sign of a less favorable outcome, while a triple-line pattern appears to be associated with conception (12-14).

In this prospective study, we aimed to show the role of combined endometrial thickness and endometrial pattern in predicting the success of ICSI cycles.

2. Patients and methods

This study was performed on 100 women who attended the Egyptian International Fertility/IVF center in Misr El Dawly Hospital, Dokki, Egypt, aiming to get pregnant through IVF technique, in the period from September 2011 to November 2012.

The study included women who were aged 20-42 years, who all had fresh IVF/ICSI cycles regardless of the type of infertility or the cause of infertility. Women who were >42 years old were excluded. Women with known intrauterine anomalies, fibroids or tubal hydrosalpinges were also excluded.

For ovarian stimulation, the long protocol was used in all cases. For all cases, assessment of the case included day 2-3 serum FSH, LH, Estradiol (E2) and prolactin to obtain basal levels.

Combined oral contraceptive pills (OCP) (Gynera, 0.03 mg ethinylestradiol/0.075 mg gestodene coated tablets, Bayer Schering Pharma) were given one tablet daily for 21 days starting from the first day of the cycle prior to the cycle of controlled ovarian hyperstimulation (COH). On day 21 of the cycle prior to the cycle of COH, GnRH agonist (triptorelin acetate) 0.1 mg S.C. injection (Decapeptyl, Ferring Pharmaceuticals) was given once daily for 10-14 days.

On day 2-3 of the menstrual cycle induced by the withdrawal of OCP, serum Estradiol (E2) was measured, and vaginal ultrasound was done to detect the antral follicle count and to exclude the presence of ovarian cysts. When serum E2 is 630 pg/ml, COH was initiated.

COH was achieved with administration of gonadotrophin in the form of human menopausal gonadotrophin (HMG). The drugs used were either (Merional, IBSA, Institut Biochimique SA), (Menogon, Ferring Pharmaceuticals) or (Meno-pur, Ferring, Pharmaceuticals) and initial dose ranged from 150-375 IU depending on the basal FSH level, antral follicle count and maternal age. When vaginal ultrasound showed at least 3 follicles P18 mm, serum E2 was measured, human cho-rionic gonadotrophin (HCG) 10,000 IU was given IM (Chori-omon, IBSA, Institut Biochimique SA) when serum E2 was <3000 pg/ml, but if serum E2 was >3000 pg/ml, the patient was excluded from the study. Serum progesterone was measured on the day of HCG administration.

Thirty-four to 36 hours following HCG administration, ovum pick up was performed under general anesthesia for oo-cyte retrieval. Three days later, embryo transfer was performed. Three embryos were transferred transcervically without anesthesia and with abdominal ultrasound guidance.

After oocyte retrieval, all patients were given IM progesterone injection 100 mg once daily for 14 days (Prontogest, Mar-cyrl Pharmaceutical Industries), progesterone suppositories 400 mg once daily for 14 days (cyclogest, Actavis, Barnstaple, UK), oral progesterone (dydrogesterone) 10 mg three times daily for 14 days (Duphaston, 10 mg tablets, Abbott Healthcare Products, The Netherlands), oral corticosteroids (predni-sone) 5 mg once daily for 14 days (Hostacortin, 5 mg tablets, Sanofi-Aventis, Egypt) and oral estrogen preparation (estra-diol) once daily for 14 days (Cycloprogynova, Bayer Schering Pharma).

Serum b-HCG was measured 14 days after embryo transfer. Subsequent ultrasound examinations were performed to detect gestational sacs in case of positive pregnancy test. With positive b-HCG, either prontogest or cyclogest suppositories were continued.

Clinical pregnancy was considered with identification of a gestational sac 3 weeks following embryo transfer.

2.1. Endometrial assessment

On the day of HCG administration, the endometrium was imaged for thickness and pattern. Endometrial thickness was measured through vaginal ultrasound in the mid-sagittal plane of the uterine body. The endometrial thickness was defined as the distance from the point of the endometrial-myometrial junction on one side to the same point on the other side.

Endometrial pattern was also assessed by describing the type of relative echogenicity of the endometrium compared with the adjacent myometrium (1).

Endometrial pattern noticed was either tri-laminar (triple line) [which is hypoechoic endometrium with well-defined hyperechoic outer walls and a central echogenic line] (Fig. 1), echogenic endometrium which is a homogenous hyperechoic endometrium with absent central echogenic line (Fig. 2), or intermediate endometrium which appeared as an endometrial pattern that was transitioning into an echogenic one at the myometrial and endometrial interface, but still had some elements of a well-defined central echogenic line with hypoechoic areas between these lines (15) (Fig. 3).

Figure 1 Trilaminar endometrium pattern.

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Figure 2 Echogenic endometrium pattern.

Figure 3 Intermediate endometrium pattern.

2.2. Statistical analysis

Statistic Package for Social Sciences (SPSS v 17.0 for Windows, Chicago, IL) software was used for data analysis. Statistical significance was assessed using the Student's t-test, y2 test and ANOVA test as appropriate data were log-transformed to correct for skewness prior to statistical analysis and values in

the two groups were compared using the Mann-Whitney u test and kruskal-wallis test. Significance was interpreted as p < 0.05. All data were presented as mean ± SD.

3. Results

A total of 100 cases were enrolled in the study. The overall clinical pregnancy rate was 62% and the early miscarriage rate (pregnancy ending before 12 weeks) was 10%.

Seventy percent of the study population had primary infertility and 30% had secondary infertility. Seventy-seven patients had ICSI for the first time and 23 patients had previous trials for ICSI.

The endometrial thickness of the study population ranged from 4 to 15 mm. The patients were divided into four groups according to the endometrial thickness (4-6.9 mm, 7-9.9 mm, 10-12.9 mm, and 13-15 mm). The groups were compared for the various parameters.

There was no statistically significant difference among groups as regards age, duration of infertility, body mass index (BMI), and base line hormones (FSH, LH, E2 and prolactin levels). Also, the stimulation length and serum progesterone on the day of HCG administration were not significantly different among groups. However, the number of ampoules of HMG given and serum E2 on the day of HCG administration showed a statistically significant difference among groups (Table 1).

Clinical pregnancy rate increased from 43.75% among patients with an endometrial thickness 69.9 mm to 73.91% among patients with an endometrial thickness of 1012.9 mm. In the group of patients with an endometrial thickness of 13-15 mm, the clinical pregnancy rate declined to 61.76% with a non-statistically significant difference among the three groups, p: 0.115 (Table 2).

Most of our subjects (71%) had trilaminar endometrium on the day of HCG administration. Clinical pregnancy rate was highest in the trilaminar pattern group (69%) followed by the intermediate pattern group (50%) then the echogenic one (38.4%), however, the difference was not statistically significant (p: 0.06) (Table 3).

We tried to declare the effect of combined endometrial thickness and pattern on clinical pregnancy rate, so we calculated clinical pregnancy rate according to the endometrial

Table 1 Baseline and cycle characteristics in different endometrial thickness groups.

Endometrial thickness P value

4-6.9 mm 7-9.9 mm 10-12.9 mm 13-15 mm

(n = 4) (n = 16) (n = 46) (n = 34)

Age (years) 29.5 ± 2.51 28.37 ± 5.38 29.93 ± 4.59 28.73 ± 4.32 0.565

Duration of infertility (years) 5.5 ± 3.0 4.93 ± 2.69 5.72 ± 3.73 5.41 ± 2.95 0.872

BMI (kg/m2) 26.85 ± 4.61 28.83 ± 4.28 28.89 ± 4.49 28.32 ± 3.47 0.766

Baseline FSH (mIU/ml) 5.52 ± 0.8 6.97 ± 1.65 7.09 ± 1.78 6.84 ± 1.85 0.394

Baseline LH (mIU/ml) 5.8 ± 1.6 6.4 ± 2.01 6.72 ± 2.57 6.55 ± 2.39 0.878

Baseline serum E2 (pg/ml) 59.5 ± 4.43 66.68 ± 5.01 63.76 ± 7.93 64.52 ± 7.02 0.28

Baseline prolactin (ng/ml) 12.8 ± 4.61 15.37 ± 4.08 14.79 ± 5.3 15.43 ± 5.38 0.769

Stimulation length (days) 10.75 ± 1.5 10.93 ± 0.92 10.86 ± 1.14 10.58 ± 0.85 0.601

Number of HMG ampoules used 53 ± 15.01 44.12 ± 9.48 39.91 ± 9.47 39.21 ± 9.11 0.026

Serum E2 on the day of HCG (pg/ml) 1203.5 ± 478.62 1306 ± 512.92 2683.2 ± 2023.3 2713.8 ± 2015.1 0.003

Serum progesterone on the day of HCG (ng/ml) 1.42 ± 0.9 1.17 ± 0.36 1.26 ± 0.67 1.48 ± 0.37 0.212

Endometrial thickness on the day of HCG (mm) 4.8 ± 0.46 8.9 ± 0.11 10.97 ± 0.73 13.76 ± 0.81 0.000

Table 2 Clinical pregnancy rate according to endometrial thickness.

Endometrial thickness (mm) Number of patients Clinical pregnancy rate P value

4-6.9 4 0/4 (0%) 0.115

7-9.9 16 7/16 (43.75%)

10-12.9 46 34/46 (73.91%)

13-15 34 21/34 (61.76%)

Table 3 Distribution of pregnancy in the study population according to the endometrial pattern.

Trilaminar endometrium Intermediate endometrium Echogenic endometrium P value

Number and percentage of pregnant cases 49/71 (69%) 8/16 (50%) 5/13 (38.4%) 0.06

Table 4 Clinical pregnancy rate with different endometrial patterns in each endometrial thickness group.

Endometrial thickness

7-9.9 mm 10-12.9 mm 13-15 mm

Endometrial pattern Trilaminar 5/16 (31.25%) 26/46 (56.5%) 18/34(52.94%)

Intermediate 1/16 (6.25%) 5/46 (10.8%) 2/34 (5.88%)

Echogenic 1/16 (6.25%) 3/46 (6.5%) 1/34 (2.94%)

P value 0.107 0.043 0.062

pattern in each endometrial thickness group. In the 4-6.9 mm endometrial thickness group, no clinical pregnancy was detected. In the 7-9.9 mm, 10-12.9 mm and 13-15 mm endome-trial thickness groups, most of pregnant cases were in the trilaminar pattern group. The trilaminar endometrium in the 10-12.9 mm thickness group showed the highest clinical pregnancy rate (56.5%) compared to the other groups, with a statistically significant difference (p: 0.043) (Table 4).

4. Discussion

An association of various cycle characteristics and treatment outcome has been evaluated since the introduction of assisted reproduction technologies. One such parameter, which has been evaluated by several authors, is that of endometrial thickness (4,6-10,16-20).

Previous studies showed conflicting results as regards the effects of endometrial thickness on pregnancy outcome in IVF/ICSI cycles.

Some studies showed a significant relation between endo-metrial thickness and clinical pregnancy rate (4,6,21-23). Others showed that endometrial thickness is not a predictor of clinical pregnancy outcome (7,9,11,24).

In this study, the endometrial thickness was non-signifi-cantly different between the group of patients who got pregnant and those who did not, however, the mean endometrial thickness was higher in the pregnant group (11.6 ± 1.89 mm versus 11.1 ± 2 mm, p: 0.18). This result is similar to that reached by Barker et al., 2009 and Rashidi et al., 2005 where both reported a non-significant difference in endometrial thickness between pregnant and non-pregnant groups (8,24).

In the present study, the thinnest endometrium for successful ongoing pregnancy was 7 mm. This goes in line with the results of Oliveira et al., 1997 who reported no pregnancies when endometrial thickness was less than 7 mm (25).

We evaluated clinical pregnancy rates after dividing the endometrial thickness into four groups: 4-6.9 mm, 7-9.9 mm, 10-12.9 mm and 13-15 mm. We found that endometrial thickness of 10-12.9 mm resulted in the highest clinical pregnancy rate (73.91%) and that above 13 mm, clinical pregnancy decreases (61.76%), and 69.9 mm there is rapid decline in clinical pregnancy rate (43.75%), however, the difference showed no statistical significance (p: 0.115). Kuc et al., 2011 stated that endometrial thickness of 12-13 mm was associated with the highest pregnancy rate for the long protocols (21). Okohue et al., 2009 reported the highest pregnancy rate with an endometrial thickness of 7-14 mm (6). Traub et al., 2009 found that endometrial stripe P 9.4 mm demonstrated a sensitivity of 83% for predicting clinical pregnancy following blastocyst embryo transfer (22). This was confirmed in 2010 by Chen et al., who performed a large study on 2896 cycles and found that the highest clinical pregnancy rate was achieved with an endome-trial thickness of 9-10 mm (5). However, the optimum endo-metrial thickness that predicts successful pregnancy is not definite yet. Older studies have found that a minimum of 6 mm endometrial thickness is acceptable as a prerequisite for implantation (26,27). Also, one study reported a successful pregnancy with an endometrial thickness as little as 4 mm (28).

In this study, CPR was the highest with the trilaminar endometrium (69%) when compared with other patterns, and the difference approached statistical significance (p: 0.06). Kuc et al., 2011 reviewed 583 cycles of ICSI with different protocols of controlled ovarian hyperstimulation and reported that endometrial echogenicity had a significant influence on the pregnancy rate in the long GnRH agonist protocol (21). However, several studies have demonstrated no prognostic value of endometrial pattern for pregnancy (5,8,24,29,30). In this study, we tried to evaluate the role of combined endometrial thickness and pattern on clinical pregnancy rate. The endometrial thickness of 10-12.9 mm with trilaminar appearance produced the highest clinical pregnancy

rate (56.5%) compared to pregnancy rates in other endometrial thickness and pattern groups. In the 10-12.9 mm thickness group, the least clinical pregnancy rate was recorded in the echogenic pattern group (6.5%). Endometrial pattern affected CPR significantly in the 10-12.9 mm group in favor of the trilaminar one (p: 0.043). Serum progesterone on the day of HCG administration was significantly higher in the group of patients who did not achieve pregnancy as compared to those who got pregnant (p: 0.001). High serum progesterone makes the endometrium more echogenic; and this may explain impaired endometrial receptivity and hence decreased CPR in patients with echogenic endometrium. This is in agreement with Check et al., 1993 who found that no pregnancies occurred in those patients with homogenous hyperechoic endo-metrium (13). Chen et al. performed a study in 2010 and concluded that combined analysis of endometrial thickness and pattern on the day of HCG administration was a better predictor of the outcome of IVF/ICSI and may be more helpful for patient counseling than the separate analyses (5)

From the results of our study, we can conclude that endo-metrial thickness of 10-12.9 mm with trilaminar pattern is associated with higher clinical pregnancy rates with ICSI cycles. Larger studies are needed to make a definitive conclusion.

Conflict of interest

None. References

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