The relationship between the change in serum high sensitivity C-reactive protein levels and IVF success

High estradiol levels during a long agonist IVF protocol are associated with decreased food intake, higher leptin concentrations, and lower levels of high-sensitivity C-reactive protein

PURPOSE

To study whether different hormonal phases affect appetite regulation, food intake, and concentrations of leptin, glucagon-like peptide-1 (GLP-1), and high-sensitivity C-reactive protein (hs-CRP) during a long agonist in vitro fertilization (IVF) protocol.

METHODS

Fifty-four infertile women were encountered thrice, the first of which was at the beginning of their period (low estradiol). The other two visits were during a gonadotrophin-releasing hormone (GnRH) analog downregulation (low estradiol) and at the end of a follicle-stimulating hormone (FSH) stimulation (high estradiol). The first visit was the reference; the women served as their controls. The concentrations of leptin, GLP-1, and hs-CRP were assessed from plasma. Dietary intake was assessed using food records (FRs). In addition, weight, height, body mass index (BMI), and plasma levels of estradiol, glucose, HbA1c, insulin, and lipids were monitored. Twenty-six of the subjects also had a postprandial test.

RESULTS

During the stimulation protocol, leptin concentrations elevated (P < 0.001), and energy intake decreased (P = 0.03), while estradiol levels increased (P < 0.001). GLP-1 levels unchanged (P = 0.75) and hs-CRP (P = 0.03) concentrations diminished, while estradiol levels increased.

CONCLUSION

No increased food intake or weight gain occurred during the stimulation protocol; thus, leptin may protect from overeating during high estradiol levels, and leptin resistance may not occur during a short follow-up. Also, a favorable anti-inflammatory effect was detected. During this study, we observed no harmful metabolic effects, which might affect negatively maternal health.

Low-grade inflammation is negatively associated with live birth in women undergoing IVF

RESEARCH QUESTION

Is low-grade inflammation, detected by C-reactive protein (CRP), a marker of IVF outcome addressing both blastocyst quality and pregnancy outcome?

DESIGN

This sub-study of a multicentre randomized controlled trial included 440 women undergoing IVF treatment with a gonadotrophin-releasing hormone (GnRH) antagonist protocol. Serum CRP was measured on cycle day 2-3 (baseline) and on the day of ovulation triggering. The association between CRP concentrations and reproductive outcomes (number of retrieved oocytes, number of good-quality blastocysts, pregnancy, pregnancy loss and live birth), were analysed, adjusting for relevant confounders.

RESULTS

A negative association was found between higher baseline CRP concentrations and live birth rate (odds ratio [OR] 0.77, 95% confidence interval [CI] 0.62-0.96, P = 0.02) and higher CRP concentrations at baseline were associated with pregnancy loss among women who conceived (OR 1.37, 95% CI 1.07-1.76, P = 0.01). When testing for a specific cut-off, CRP concentrations above 2.34 (the highest quartile) were more likely to be associated with pregnancy loss (P = 0.02) and a lower chance of live birth (P = 0.04) compared with the lowest quartile. No associations were found between CRP concentrations and pregnancy outcomes on the day of ovulation triggering, and there were no associations between CRP concentrations and the number of good-quality blastocysts.

CONCLUSIONS

Higher CRP concentrations at cycle day 2-3, before starting ovarian stimulation, are negatively associated with chance of live birth, possibly because of an increased risk of pregnancy loss. No association was found between the number of good-quality blastocysts and CRP concentration. More studies are needed to investigate the impact of low-grade inflammation.

Serum C-reactive protein levels are associated with clinical pregnancy rate after in vitro fertilization among normal-weight women

OBJECTIVE

To assess whether low-grade inflammation, measured by serum high-sensitivity C-reactive protein (hsCRP) levels, is associated with in vitro fertilization (IVF) outcomes.

DESIGN

A retrospective study.

SETTING

University-affiliated IVF center.

PATIENTS

In the present study, 875 women of normal weight who underwent their first fresh embryo transfer (ET) cycles for IVF treatment were divided into three groups according to serum concentrations of hsCRP.

INTERVENTIONS

Serum from women undergoing IVF was collected on days 2-4 of a spontaneous menstrual cycle prior to the commencement of ovarian stimulation.

MAIN OUTCOME MEASURES

The IVF outcomes included implantation, biochemical pregnancy, clinical pregnancy, miscarriage and live birth rates.

RESULTS

The women were divided into three groups according to the baseline serum levels of hsCRP as follows: low hsCRP (<1 mg/L; n=517), medium hsCRP (1-3 mg/L; n= 270), high hsCRP (>3 mg/L; n=88). The maternal age was similar among the three groups. The women in the high and medium hsCRP group had significantly higher BMI compared with those in the low hsCRP group. The protocol of controlled ovarian hyperstimulation, the gonadotropin dose administered, the serum estradiol levels, progesterone levels and the endometrial thickness on the day of triggering, as well as the number of retrieved oocytes, fertilized oocytes and good quality embryos, and the oocyte maturation rate were similar among the three groups. Implantation, biochemical pregnancy and clinical miscarriage rates did not differ significantly were not significantly different among three groups. The clinical pregnancy rate was significantly lower in the high hsCRP group compared with that in the low hsCRP group (50.0% versus 63.4%; P<0.0167), which contributed to a significant decrease in birth rate (39.8% versus 53.8%; P<0.0167). High serum hsCRP levels was found to be a factor affecting live birth rate.

CONCLUSIONS

Among women of normal weight undergoing their first IVF treatment, it was found that low-grade inflammation was associated with reduced clinical pregnancy and live birth rates following fresh ET cycles.

Association between dietary inflammatory index and inflammatory biomarkers with outcomes of in vitro fertilization treatment

AIM

To investigate associations between dietary inflammatory index (DII), high-sensitivity C-reactive protein (hs-CRP) and interleukin-6 (IL-6) with outcomes of in vitro fertilization treatment.

METHODS

This observational prospective study included 144 women undergoing fresh in vitro fertilization cycles who attended infertility center of Al-Zahra Hospital in Tabriz, Iran. DII was computed based on dietary intake assessed using a 3-day 24-h food record diary. Outcomes of in vitro fertilization in this study were considered fertilization rate, embryo quality and positive pregnancy test. Inflammatory biomarkers were measured on the day of embryo transfer.

RESULTS

There was no statistically significant difference between pregnant and nonpregnant women in terms of infertility and demographic characteristics, quantity of retrieved and fertilized oocytes, fertilization rate and number of transferred embryos (P > 0.05). The mean quality scores of resultant embryos (P < 0.001) and transferred embryos (P = 0.019) were significantly lower in the group of pregnant women, indicating the better quality among them. Median (percentile 25-75th) DII in the pregnant women was 1.8 (0.5-2.7) and in the nonpregnant women was 1.6 (0.3-2.6). DII was significantly related to hs-CRP (r = 0.198, P = 0.017) but not to IL-6. There were no significant relationships between DII, serum hs-CRP, IL-6 and in vitro fertilization outcomes (P > 0.05).

CONCLUSION

These findings demonstrate that serum hs-CRP and IL-6 concentration and DII are not predictive markers of in vitro fertilization cycle outcomes in women undergoing in vitro fertilization.

Maternal C-reactive protein and in vitro fertilization (IVF) cycles

Embryo implantation is accompanied by a potent inflammatory response, and a gradient of cytokines and chemokines produced by endometrial cells supports the embryo-endometrial interaction. C-reactive protein (CRP) serves as an early marker of inflammation and recent studies have illustrated that controlled ovarian hyperstimulation (COH) could increase its levels. Interestingly, a high chance of pregnancy has been reported in women who had an elevated CRP level on the day of embryo transfer. It seems an elevated systemic inflammation in the in vitro fertilization (IVF) cycle can increase the implantation and pregnancy rates. However, the results regarding the association of CRP with ART outcomes are controversial. Therefore, in this review, we aimed to describe how CRP levels change during a cycle of IVF treatment and which factors can potentially affect this pattern of change. Furthermore, the association of CRP with ART outcomes has been discussed.

C-reactive protein and ART outcomes: a systematic review

BACKGROUND

A dynamic balance between pro- and anti-inflammatory factors contributes to regulating human female reproduction. Chronic low-grade inflammation has been detected in several female reproductive conditions, from anovulation to embryo implantation failure. C-reactive protein (CRP) is a reliable marker of inflammation that is extensively used in clinical practice. Recent studies quantified CRP in the serum of infertile women undergoing ART and suggested its potential for the prediction of ART reproductive outcomes.

OBJECTIVE AND RATIONALE

The first objective of this systematic review of the available literature was to evaluate the association between pre-implantation circulating CRP concentration and pregnancy rates in women undergoing ART. The second objective was to describe serum CRP concentration changes after early embryo implantation. The changes in circulating CRP throughout the ART cycle, clinical implications of CRP quantification for the management of women undergoing ART, and future therapeutic options will also be discussed.

SEARCH METHODS

The MEDLINE database was systematically searched from inception to March 2019 using the following key words: (C-reactive protein) AND (assisted reproductive techniques OR ovulation induction OR insemination OR in vitro fertilization). Only articles in English were considered. Studies were selected based on title and abstract. The full text of potentially relevant articles was retrieved and assessed for inclusion by two reviewers (S.B. and S.H.). The protocol was registered in the International prospective register of systematic reviews (PROSPERO; registration number: CRD148687).

OUTCOMES

In total, 10 studies were included in this systematic review. Most of these studies reported lower circulating CRP values before the window of implantation and higher circulating CRP values during the peri-implantation period in women with successful ART outcome (biochemical or clinical pregnancy) compared to women without a successful outcome. Several lifestyle factors and/or drugs that reduce the concentration of circulating CRP significantly improve ART outcomes. Subgroup analyses according to female BMI and baseline circulating CRP concentration are highly recommended in future analyses.

WIDER IMPLICATIONS

These findings highlight a possible detrimental impact of preconception high circulating CRP concentration on ART outcomes. However, the biochemical or clinical pregnancy rate endpoints used in the studies examined here are insufficient (there were no data on live birth outcome), and the impact of major variables that can influence CRP and/or ART, for example maternal age, BMI, number of transferred embryos, and use of anti-inflammatory drugs, were not considered in the analyses. CRP quantification may be a potential marker of ART outcome, but its predictive value still needs to be investigated in large prospective studies. In future, the quantification of circulating CRP before starting ART could help to identify patients with a poor ART prognosis, leading to ART cycle cancellation or to preconception treatment to minimize the medical risks and costs.

C-reactive protein response is higher in early than in late ovarian hyperstimulation syndrome

OBJECTIVES

Many in vitro fertilization (IVF) complications are inflammatory by nature, some of which are even life-threatening. We evaluated the response of C-reactive protein (CRP) in IVF complications, especially in early and late ovarian hyperstimulation syndrome (OHSS), to support clinical decision making in gynecological emergency policlinics.

STUDY DESIGN

In a prospective two-year study at Helsinki University Hospital, Finland, we recruited patients with IVF complications including moderate or severe OHSS (n=47 patients: 36 early and 14 late OHSS cases), or other IVF complications (n=13). As controls, we recruited women in an uncomplicated IVF cycle (n=27). Serial blood samples (CRP, blood count, platelets, albumin, estradiol, creatinine, and electrolytes) were collected from patients upon admission to the emergency polyclinic and during and after treatment on the ward, and from the controls prior, during, and after the IVF protocol. All samples were categorized according to oocyte pick-up (OPU). The statistics included comparisons between and within the study groups, and receiver-operating characteristic (ROC) curve analysis for diagnostic accuracy of CRP for early OHSS at emergency polyclinics.

RESULTS

On admission, CRP did not differentiate OHSS from other IVF complications, but CRP was higher in early (median 21; IQR 8-33mg/L) than in late (6; 3-9mg/L, p=0.001) OHSS. In ROC analysis for CRP (12mg/L), the area under the curve (AUC) was 0.74 (p=0.001) with sensitivity of 69% and specificity of 71% for early OHSS. CRP was significantly higher (28; 10-46mg/L) in patients with early OHSS two days after oocyte pick-up (OPU) than in the controls (5; <3-9mg/L, p<0.001). The level normalized by 12 days, similarly to the controls. On the ward, the peak CRP was higher if early OHSS was complicated with infection (108; 49-166mg/L) than without infection (20; 8-32mg/L, p=0.001). Late OHSS was associated with hypoalbuminemia (19.6; 16.2-23.1g/L, p<0.001) and thrombocytosis (494; 427-561 E9/L, p=0.004; comparisons to early OHSS).

CONCLUSIONS

Early OHSS associates with a distinct rise in CRP level beyond that induced by uncomplicated oocyte pick-up, whereas the CRP levels in late OHSS are comparable to those in the control cycles. CRP identifies, but cannot distinguish IVF complications.

Evaluation of human chaperonin 10 and high-sensitivity C-reactive protein levels of infertile women who underwent ovulation induction and intra-uterine insemination

INTRODUCTION

The implantation of embryo is one of the crucial steps of a successful pregnancy. The foetus should be protected from maternal immune system, for the appropriate implantation and modification in maternal immunity is crucial. We investigated high-sensitivity C-reactive protein (hs CRP), which is an indicator of low-grade inflammation and Cp10 that has immunosuppressant and growth-promoting capabilities at embryo levels in ovulation induction and intra-uterine insemination (IUI)applied in infertile women. The ovulation induction was maintained by clomiphene citrate or gonadotropins for 42 infertile patients. After successful ovulation induction, IUI was carried out. The blood samples were taken 2 and 8 days after IUI to evaluate Cp10 and hs CRP levels. The pregnant and non-pregnant groups' results were analyzed. The Cp10 levels 8 days after IUI were higher in pregnant group, whereas there was no difference for the 2 days after levels between pregnant and non-pregnant group. The hs CRP levels were similar for both 2nd and 8th days when we compared pregnant and non-pregnant groups. The Cp10 levels increased from day 2 to day 8 in pregnant group. In contrast, the Cp10 levels decreased in non-pregnant group. The change in hs CRP levels from day 2 to day 8 was not significant in pregnant and non-pregnant groups. The Cp10 levels were higher in early phases of fertilisation and elevated through the preceding days of conception in pregnant patients, while it decreased in non-pregnant patients with failed cycles.