Effect of follicular diameter at the time of ovulation triggering on pregnancy outcomes during intrauterine insemination

Effect of the degree of follicular diameter ≥18mm differentiation on the day of hCG administration to the outcome of controlled ovarian hyperstimulation (COH)

Objective

To explore the impact of the level of differentiation in a minimum of two follicles with a diameter of ≥18 mm on the outcome of controlled ovarian hyperstimulation on the day of human chorionic gonadotropin (hCG) administration.

Methods

Single-center data from January 2018 to December 2021 was retrospectively analyzed for 1,199 patients with fresh embryo transfer for assisted reproduction. The absolute value of the standard deviation of the follicle size of at least 2 follicles ≥18 mm in diameter in both ovaries on the day of hCG was taken as the degree of differentiation of the dominant follicle after ovulation induction, based on the standard deviation response to the degree of dispersion of the data. The degree of follicular differentiation was divided into 3 groups according to the size of the value, and the general clinical conditions, laboratory indexes, and clinical outcomes of the patients in the 3 groups were compared.

Results

Among the three groups, the body mass index (BMI) of the ≤1s group was lower than that of the other two groups (P< 0.05), while the follicle-stimulating hormone (FSH) and Anti-Mullerian hormone (AMH) were higher (P< 0.05), and the implantation rate and clinical pregnancy rate were significantly higher than those of the other two groups (P< 0.01). After multifactorial logistic regression to correct for confounding factors, with the ≤1s group as the reference, the implantation rate, hCG-positive rate, clinical pregnancy rate and live birth rate of embryo transfer in the ≥2S group were significantly lower (P< 0.01). The results of curve fitting analysis showed that the live birth rate decreased gradually with the increase of the absolute standard deviation (P=0.0079).

Conclusion

Differences in follicle diameters ≥18 mm on the day of hCG injection did not have an impact on embryo quality, but had an impact on pregnancy outcomes. The less the variation in follicle size, the more homogeneous the follicle development and the higher the likelihood of live births.

Low Estradiol Level and Endometrial Thickness on the Day of Endometrial Transformation Influence Clinical Pregnancy After Intrauterine Insemination

Background

The causes of pregnancy failure after intrauterine insemination (IUI) are controversial. The purpose of this study was to investigate the influencing factors on clinical pregnancy after IUI.

Methods

This study retrospectively analyzed 1464 cycles of IUI performed at the Meizhou People's Hospital between March 2014 and June 2023. The χ2 test and logistic regression analysis was applied to assess the associations between the some factors (maternal age, paternal age, cycle type (natural cycle or ovulation induction cycle), hormone level on the day of endometrial transformation (estradiol (E2), luteinizing hormone (LH), and progesterone (P)), endometrial thickness on the day of endometrial transformation, and forward motile sperm concentration after treatment) and pregnancy failure.

Results

Among the 1464 IUI cycles in this study, 268 cycles of assisted reproduction resulted in clinical pregnancy, with a clinical pregnancy rate of 18.3%. During the cycles with clinical pregnancy, there were 25 (12.9%) preterm births and 169 (87.1%) full-term births. The E2 level on the day of endometrial transformation in clinical pregnancy group was higher than that in the pregnancy failure group (658.79±656.02 vs 561.21±558.83 pg/mL)(P=0.025). The clinical pregnancy group had a higher percentage of endometrial thickness between 8 and 13mm on the day of endometrial transformation than the pregnancy failure group (83.2% vs 75.0%)(P=0.002). The results of regressions analysis showed that low E2 level on the day of endometrial transformation (<238.3 pg/mL vs ≥238.3 pg/mL: OR 1.493, 95% CI: 1.086-2.052, P=0.014), and endometrial thickness <8mm on the day of endometrial transformation (<8mm vs 8-13mm: OR 1.886, 95% CI: 1.284-2.771, P=0.001) may increase risk of pregnancy failure performed IUI.

Conclusion

Low estradiol level, and endometrial thickness on the day of endometrial transformation may increase risk of pregnancy failure performed intrauterine insemination.

Effect of follicle size on pregnancy outcomes in patients undergoing first letrozole-intrauterine insemination

BACKGROUND

Letrozole has been proven to be an effective method for inducing ovulation. However, little attention has been paid to whether the lead follicle size will affect the success rate of intrauterine insemination (IUI) with ovulation induction with alone letrozole. Therefore, we hope to investigate the effect of dominant follicle size on pregnancy outcomes on human chorionic gonadotropin (hCG) day of the first letrozole-IUI.

METHODS

A retrospective cohort study design was employed. We included patients with anovulation or unexplained infertility undergoing first IUI treatment with letrozole for ovarian stimulation. According to the dominant follicle size measured on the day of hCG trigger, patients were divided into six groups (≤ 18 mm, 18.1-19.0 mm, 19.1-20.0 mm, 20.1-21.0 mm, 21.1-22.0 mm, > 22 mm). Logistic models were used for estimating the odds ratios (ORs) with their 95% confidence interval (CIs) for achieving a clinical pregnancy or a live birth. A restricted cubic spline was drawn to explore the nonlinear relationship between follicle size and IUI outcomes.

RESULTS

A total of 763 patients underwent first letrozole-IUI cycles in our study. Fisher exact test showed significant differences among the six follicle-size groups in the rates of pregnancy, clinical pregnancy and live birth (P < 0.05 in each group). After adjusting the potential confounding factors, compared with the follicles ≤ 18 mm in diameter group, 19.1-20.0 mm, 20.1-21.0 mm groups were 2.3 or 2.56 times more likely to get live birth [adjusted OR = 2.34, 95%CI (1.25-4.39); adjusted OR = 2.56, 95% CI (1.30-5.06)]. A restricted cubic spline showed an inverted U-shaped relationship between the size of dominant follicles and pregnancy rate, clinical pregnancy rate, and live birth rate, and the optimal follicle size range on the day of hCG trigger was 19.1-21.0 mm. When the E2 level on the day of hCG trigger was low than 200 pg/mL, the clinical pregnancy rates of 19.1-20.0 mm, 20.1-21.0 mm groups were still the highest.

CONCLUSIONS

The optimal dominant follicle size was between 19.1 and 21.0 mm in hCG-triggered letrozole-IUI cycles. Either too large or too small follicles may lead to a decrease in pregnancy rate. Using follicle size as a predicator of pregnancy outcomes is more meaningful when estrogen on the day of hCG trigger is less than 200 pg/ml.

Follicular phase length is not related to live birth outcome in women with unexplained infertility undergoing ovarian stimulation with intrauterine insemination cycles in a multicenter trial

Objective

To evaluate the effect of follicular phase length (FPL) on pregnancy outcomes and endometrial thickness (ET) among women with unexplained infertility undergoing ovarian stimulation with intrauterine insemination (OS-IUI) with clomiphene citrate, letrozole, or gonadotropins.

Design

Cohort analysis of the Reproductive Medicine Network's Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation randomized controlled trial.

Setting

Multicenter randomized controlled trial.

Patients

A total of 869 couples with unexplained infertility who underwent OS-IUI treatment cycles as part of the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation study.

Interventions

FPL was evaluated as a categorical variable defined by quintiles (q1: ≤11 days, q2: 12 days, q3: 13 days, q4: 14-15 days, and q5: ≥16 days).

Main outcome measures

Clinical pregnancy, live birth rates, and ET.

Results

Decreasing FPL quintiles did not reduce clinical pregnancy or live birth rates in unadjusted or adjusted models with all treatment groups combined or when stratified by the ovarian stimulation medication. All FPL categories had significantly thinner ET compared with the 5th quintile (≥16 days) among women treated with clomiphene citrate or letrozole. Similar but diminished associations were observed among women who underwent ovarian stimulation with gonadotropins, but the observed differences were limited to those with FPL of 12 days or shorter when compared with FPL ≥16 days.

Conclusions

Although shorter FPL was associated with reduced ET, it was not associated with the outcomes of clinical pregnancy or live birth in women with unexplained infertility undergoing OS-IUI in all treatment groups combined. Similar patterns existed when analyses of clinical pregnancy and live birth rates were stratified by treatment.

Clinical trial registration

NCT01044862.

The importance of infertility duration and follicle size according to pregnancy success in women undergoing ovulation induction with gonadotropins and intrauterine insemination

In this study, we aimed to evaluate the effect of infertility duration and dominant follicle size measured on the day of human chorionic gonadotropin (HCG) administration on pregnancy rates in infertile women undergoing ovulation induction (OI) with gonadotropin (GND). A total of 352 patients aged 20 to 41 years who were diagnosed with unexplained infertility or polycystic ovary syndrome (PCOS) were included in this study. Patients with a history of multifollicular development or follicle stimulating hormone (FSH) value more than 12 IU/ml were excluded from the study. The demographic and clinical features of the patients were obtained from the patients' files and hospital automation system and recorded for each woman. The demographic and clinical features of the patients were recorded. Patients were divided into two groups as live birth (group 1, n = 47) and non-live birth groups (group 2, n = 305). There were no statistically significant differences in regard to age, infertility type, follicle stimulating hormone (FSH) level, oestradiol (E2) level, antral follicle count (AFC), cycle characteristics, GND type, number of follicles, E2 level and endometrial thickness on HCG day, total GND dose, dominant follicle size (p > 0.05). Infertility duration in group 1 was 3.5 ± 2.1; in group 2, 4.7 ± 3.9 years. This difference was statistically significant (p = .014). According to this study, live birth rates after GND + IUIs(intrauterine insemination) were significantly affected by the duration of infertility. But the dominant follicle size and endometrial thickness measured on HCG day in GND and IUI cycles did not have a significant effect on pregnancy rates.IMPACT STATEMENTWhat is already known on the subject? It is thought that the timing of the ovarian triggering is vital for the success of intrauterine insemmination (IUI) treatment.What do the results of this study add? According to our results live birth rates after GND + IUIs were significantly affected by the duration of infertility.What are the implications of these findings for clinical practice and/or further research? It is determined that the duration of infertility is significant and patients should be encouraged to the treatment as soon as possible.

The definition of unexplained infertility: A systematic review

BACKGROUND

There is no consensus on tests required to either diagnose unexplained infertility or use for research inclusion criteria. This leads to heterogeneity and bias affecting meta-analysis and best practice advice.

OBJECTIVES

This systematic review analyses the variability of inclusion criteria applied to couples with unexplained infertility. We propose standardised criteria for use both in future research studies and clinical diagnosis.

SEARCH STRATEGY

CINAHL and MEDLINE online databases were searched up to November 2022 for all published studies recruiting couples with unexplained infertility, available in full text in the English language.

DATA COLLECTION AND ANALYSIS

Data were collected in an Excel spreadsheet. Results were analysed per category and methodology or reference range.

MAIN RESULTS

Of 375 relevant studies, only 258 defined their inclusion criteria. The most commonly applied inclusion criteria were semen analysis, tubal patency and assessment of ovulation in 220 (85%), 232 (90%), 205 (79.5%) respectively. Only 87/220 (39.5%) studies reporting semen analysis used the World Health Organization (WHO) limits. Tubal patency was accepted if bilateral in 145/232 (62.5%) and if unilateral in 24/232 (10.3%). Ovulation was assessed using mid-luteal serum progesterone in 115/205 (56.1%) and by a history of regular cycles in 87/205 (42.4%). Other criteria, including uterine cavity assessment and hormone profile, were applied in less than 50% of included studies.

CONCLUSIONS

This review highlights the heterogeneity among studied populations with unexplained infertility. Development and application of internationally accepted criteria will improve the quality of research and future clinical care.

The effect of gonadotrophin-releasing hormone agonist versus human chorionic gonadotrophin trigger on pregnancy and neonatal outcomes in Letrozole-HMG IUI cycles

BACKGROUND

GnRHa and hCG are both used for oocyte maturation and ovulation triggering. However, GnRHa have a shorter half-life than hCG, which leads to luteal phase deficiency. Letrozole (LE) has been found to improve the luteal function. Thus, the choice of triggering strategy can be different in intrauterine insemination (IUI) cycles using LE and human menopausal gonadotropin (HMG). The aim of this study was to compare the pregnancy and neonatal outcomes of patients triggered with GnRHa versus hCG versus dual trigger in LE-IUI cycles.

METHODS

This retrospective cohort study included 6,075 LE-HMG IUI cycles between January 2010 and May 2021 at a tertiary-care academic medical center in China. All cycles were divided into three groups according to different trigger strategies as hCG trigger group, GnRHa trigger group and dual trigger group. The primary outcome was clinical pregnancy rate. Logistic regression analysis was performed to explore other risk factors for clinical pregnancy rate.

RESULTS

No significant difference was observed in clinical pregnancy rate between hCG, GnRHa and dual trigger cycles in LE-HMG IUI cycles (P = 0.964). The miscarriage rate was significantly lower in the GnRHa trigger group, and higher in the dual trigger group, compared with the hCG group (P = 0.045). Logistic analysis confirmed that triggering strategy was associated with miscarriage (aOR:0.427, 95%CI: 0.183-0.996, P = 0.049; aOR:0.298, 95%CI: 0.128-0.693, P = 0.005). No significant differences were observed regarding neonatal outcomes between the three groups.

CONCLUSIONS

Our findings suggested that both GnRHa and dual trigger can be used to trigger ovulation in LE-HMG IUI cycles, but dual trigger must be used with caution.

Optimal lead follicle size in letrozole human menopausal gonadotrophin intrauterine insemination cycles with and without spontaneous LH surge

RESEARCH QUESTION

What is the optimal lead follicle size in letrozole, human menopausal gonadotrophin and intrauterine insemination (IUI) cycles with and without spontaneous LH surges?

DESIGN

This retrospective cohort study included 3797 letrozole HMG IUI cycles between January 2010 and May 2021. All cycles were divided into two groups: the HCG trigger group (trigger day LH ≤15 mIU/ml) and the spontaneous LH surge group (trigger day LH >15 mIU/ml). These two groups were subdivided into smaller groups based on the diameter of the follicles. The primary outcome measure was clinical pregnancy rate. Logistic regression analysis was conducted to explore other risk factors.

RESULTS

In the HCG trigger group, the clinical pregnancy rate varied significantly, with rates of 20.8%, 14.9% and 11.8% for the 16.1-18.0, 18.1-20.0 and 20.1-22.0 mm groups, respectively (P = 0.005). In the spontaneous LH surge group, the pregnancy rate of follicles within 14.1-16.0 mm was significantly higher than that of follicles within 20.1-22.0 mm (adjusted OR 0.533, 95% CI 0.308 to 0.923, P = 0.025). Also, patients with two lead follicles were 2.569 times more likely to achieve a clinical pregnancy than those with only one lead follicle (adjusted OR 2.569, 95% CI 1.258 to 5.246, P = 0.010). The duration of infertility was also found to be a common influencing factor in both groups.

CONCLUSIONS

The optimal lead follicle size was between 16.1 and 18.0 mm in HCG-triggered letrozole HMG IUI cycles. If the lead follicle size is relatively small (14.1-18.0 mm) when a spontaneous LH surge occurs, there is no need to cancel the IUI cycle.

The Effect of Spontaneous LH Surges on Pregnancy Outcomes in Patients Undergoing Letrozole-HMG IUI: A Retrospective Analysis of 6,285 Cycles

BACKGROUND

To date, no consensus has been reached on whether to wait for spontaneous luteinizing hormone (LH) surge to occur or to trigger ovulation regardless of the presence of an LH surge for achieving higher success rate in intrauterine insemination (IUI) cycles. Therefore, we hope to investigate the effect of the presence of a spontaneous LH surge on pregnancy outcomes in letrozole-human menopausal gonadotropin (LE-HMG) IUI cycles.

METHODS

In this retrospective cohort study, a total of 6,285 LE-HMG IUI cycles were included between January 2010 and May 2021. Cycles were categorized into three groups: the trigger + LH surge group, the trigger only group, and the LH surge only group. The primary outcome measure was the clinical pregnancy rate. A logistic regression analysis was performed to explore other risk factors affecting the clinical pregnancy rate.

RESULTS

No significant differences were observed in biochemical pregnancy rate (P =0.640), clinical pregnancy rate (P =0.702), ongoing pregnancy rate (P =0.842), and live birth rate (P =0.951) among the three groups. The binary logistic regression analysis also confirmed that the existence of an LH surge was not associated with clinical pregnancy. There was a difference in ectopic pregnancy rates (P =0.045), but logistic regression showed that the presence of a spontaneous LH surge has no association with ectopic pregnancy. Nonetheless, patients with lead follicles within 18.1-20.0 mm/20.1-22.0 mm and a long duration of LE treatment were less likely to get ectopic pregnant compared with patients with 14.1-16.0 mm lead follicles and shorter LE treatment (OR: 0.142, 95% CI: 0.023-0.891, P =0.037; OR: 0.142, 95% CI: 0.022-0.903, P =0.039; OR: 0.445, 95% CI: 0.235-0.840, P = 0.013).

CONCLUSIONS

The presence of a spontaneous LH surge in triggered LE-HMG IUI cycles does not appear to improve pregnancy rates. Thus, we suggest that waiting for an LH surge to occur is not necessary in triggered LE-HMG IUI cycles.

Correlation between total sperm count and sperm motility and pregnancy rate in couples undergoing intrauterine insemination

The frequency and significance of sterility is increasing due to different socio-demographic factors in the industrialized countries. At the same time, the patients' demand for more natural and less invasive fertility treatments is increasing. The most common method used in subfertility is intrauterine insemination (IUI). Retrospectively, the data from the patients were analyzed, in which at least one insemination and a maximum of eight inseminations were performed in the last five years (observation period 01.01.2014-31.12.2018) at the Women's University Hospital Homburg. The primary endpoint was the onset of a clinical pregnancy. Clinical pregnancy was correlated with the partner's total sperm count (sperm density in millions), sperm concentration and motility during insemination. These three parameters were evaluated according the World Health Organization (WHO) 2010 guidelines. The results of the spermiograms were correlated with clinical pregnancy outcome. The data were examined for 138 women with sterility, in which a total of 345 inseminations were performed (median 2.5 per woman, range 8 inseminations). There was no correlation found between spermiogram parameters and pregnancy probability in any of the inseminations. After 5 inseminations no further pregnancy occurred. The present study showed no correlation between the conception probability of intrauterine insemination (IUI) and the total sperm count/concentration/motility. After the sixth IUI, we no longer found conceptions in our patient collective. Therefore, data from this study indicate that intrauterine inseminations can be performed at all severity levels of oligoasthenozoospermia. However, the treatment should be limited to five attempts.