A rise of the serum level of von Willebrand factor occurs before clinical manifestation of the severe form of ovarian hyperstimulation syndrome

ABO blood group and ovarian reserve: a meta-analysis and systematic review

Ovarian reserve reflects a woman's fertility potential. The ABO blood group system is a very stable genetic marker. Although many recent studies have explored the relationship between ABO blood group and ovarian reserve, a consensus has not yet been reached. This paper is the first meta-analysis and systematic review of the relationship between ABO blood type and ovarian reserve. We analyzed seven cross-sectional studies evaluating follicle stimulating hormone (FSH) or anti-Mullerian hormone (AMH) levels in 55,113 participants to determine ovarian reserve. This study found no relationship between ABO blood type and ovarian reserve when FSH was used as an indicator of ovarian reserve (A vs non-A:OR=1.03, 95% CI:0.96-1.11; B vs non-B: OR=0.98, 95% CI:0.75-1.29; AB vs non-AB:OR=0.96, 95% CI:0.71-1.30; O vs non-O:OR=1.03, 95%CI:0.74-1.43).There was also no relationship between ABO blood type and ovarian reserve when AMH was used as an indicator (A vs non-A:OR=0.89, 95% CI:0.76-1.03; B vs non-B:OR=1.02, 95% CI:0.80-1.30; AB vs non-AB:OR=1.14, 95% CI:0.80-1.64, O vs non-O:OR=1.07, 95% CI:0.86-1.34). Overall, the current study found no relationship between ABO blood group and ovarian reserve. However, additional rigorous, high-quality and multi-indicator studies with large sample sizes are required for further verification.

A New Perspective on the Risk of Hypercoagulopathy in Ovarian Hyperstimulation Syndrome Using Thromboelastography

Thromboelastography (TEG) provides real-time assessment of hemostasis by measuring the viscoelastic properties, coagulation factor, and platelet activity in whole blood samples. In this prospective case-control study, we wanted to investigate whether blood clot formation assessment, using TEG, can identify a hypercoagulable state in women with severe ovarian hyperstimulation syndrome (OHSS). Thirty-six women who were hospitalized with severe OHSS were allocated to the OHSS group and 32 women undergoing controlled ovarian hyperstimulation but who did not develop OHSS were allocated to the control group. The TEG indices were compared between women with severe OHSS and controls. All the coagulation indices assessed by TEG were significantly different in the OHSS group compared to the controls, depicting a hypercoagulable state. Median coagulation index was 3.6 (interquartile range: 2.80-4.15) and 1.45 (interquartile range: 0.20-2.30) in study group and controls, respectively ( P < .001). Our results show that TEG can be used to depict a hypercoagulable state in women with severe OHSS.

Association of blood group A with early-onset ovarian hyperstimulation syndrome

PURPOSE OF THE STUDY

Ovarian hyperstimulation syndrome is a potentially life-threatening complication during controlled ovarian stimulation for fertility treatment. Since no association of this condition with ABO blood groups was known, we compared ABO antigens with severity and onset of symptoms in a case-control study.

PATIENTS AND METHODS

One hundred and twenty-one patients, mainly Caucasians, were hospitalized because of ovarian hyperstimulation syndrome after receiving in vitro fertilisation, in the period from January 2000 to February 2007. Severity of symptoms, pregnancy rate and ABO blood group were collated. The ABO blood group distribution was compared to four independent control groups.

RESULTS

Blood group A was markedly more frequent and blood group O less frequent in patients with ovarian hyperstimulation syndrome compared to the blood group distribution in all control cohorts. The odds ratio for patients undergoing controlled ovarian stimulation with blood group A versus O to develop the early-onset form of this condition was 2.171 (p-value 0.002). No association for late-onset form could be found. The overall pregnancy rate was 50.4% and three times higher in the group of late-onset ovarian hyperstimulation syndrome compared to the early-onset form. Four patients developed thromboses in the jugular or subclavian vein, none of whom had blood group O.

CONCLUSION

Blood group A may be associated with early-onset ovarian hyperstimulation syndrome in Caucasians. Depending on further studies, this possible association may be considered for an individualized hormone dosing in controlled ovarian stimulation.

The “ART” of thromboembolism: A review of assisted reproductive technology and thromboembolic complications

Since its development over 25 years ago, the use of assisted reproductive technology (ART) is on the increase. Along with its use, are also reports of thromboembolic complications (TEC); these events could resulted in significant maternal morbidity and even mortality. In this article, we reviewed the general principles of ART. We also performed a search of all published cases of TEC associated with ART, and summarized the results of studies investigating underlying hemostatic changes with ART. The goal of this article is to provide non-fertility specialists an understanding of ART, so as to better manage TEC when they occur in predisposed patients. The most common ART procedure performed today, is in-vitro fertilization-embryo transfer (IVF-ET). The process of IVF involves the use of exogeneous hormones to achieve cycle control, stimulate the ovaries, and support implantation. During this process, supraphysiological estradiol levels can result. One major complication of this intervention, ovarian hyperstimulation syndrome (OHSS), can be associated with both arterial and venous thrombotic complications. These events (especially venous thrombosis) have also been reported to occur weeks after OHSS has resolved; and they can present in unusual sites (upper extremities) resulting in treatment challenges. From current available studies, it is clear that with ovarian stimulation, both the coagulation and fibrinolytic systems are activated. This activation appears to be exaggerated and prolonged with the development of OHSS. Whether these changes are sufficient by themselves to explain the occurrence of TEC is yet unknown. Future studies should be focused on defining the frequency and risk factors of these complications; provide a closer examination of the resultant changes in the coagulation cascade during ART, OHSS and early pregnancy; and investigating the appropriate treatment and thromboprophylaxis for patients undergoing a procedure considered "elective".

Vascular endothelial growth factor levels in serum and plasma from patients undergoing controlled ovarian hyperstimulation for IVF

BACKGROUND

Vascular endothelial growth factor (VEGF) has been investigated as a marker of ovarian response to controlled ovarian hyperstimulation and as a predictor of ovarian hyperstimulation syndrome (OHSS) in IVF cycles. In most studies, serum has been used for circulating VEGF concentration measurement, but it has been suggested that plasma is the preferred medium to measure VEGF levels because of the potential contribution of VEGF released from platelets during blood clotting. This study investigated VEGF concentrations in paired serum and plasma samples from patients undergoing controlled ovarian hyperstimulation for IVF.

METHODS

Serum and plasma VEGF levels, as well as the number of platelets, were measured in 30 IVF patients who comprised three study groups delineated according to the estradiol (E(2)) serum concentration reached on the day of HCG administration: 10 patients having low E(2) serum levels (<1500 pg/ml, group L), 10 patients having intermediate E(2) serum levels (1500-3000 pg/ml, group I) and 10 patients having high E(2) serum levels (>3000 pg/ml, group H).

RESULTS

There was a statistically significant correlation between plasma and serum VEGF levels (rho = 0.61; P < 0.005) for the entire population studied, although serum values were higher by a factor of approximately 6-fold. No significant correlation was found between peripheral blood VEGF concentrations and serum E(2) or follicle number on HCG day or the number of oocytes collected. Similarly, paired serum and plasma VEGF measurements did not correlate with platelet count.

CONCLUSIONS

Serum and plasma VEGF concentrations are strongly correlated in paired samples from infertile patients undergoing controlled ovarian hyperstimulation. However, neither serum nor plasma VEGF levels were correlated with parameters associated with ovarian follicular activity. Peripheral blood VEGF levels were not correlated with platelet count.

New concepts in the understanding of the ovarian hyperstimulation syndrome

PURPOSE OF REVIEW

In this review we will evaluate the recent developments in the pathophysiology of the ovarian hyperstimulation syndrome, with special emphasis on mediators of human chorionic gonadotropin action.

RECENT FINDINGS

From all the different molecules investigated, it seems that vascular endothelial growth factor is the key mediator of human chorionic gonadotropin action on the vascular tree. Recent data show that although absolute serum vascular endothelial growth factor values are useless in predicting the occurrence of ovarian hyperstimulation syndrome, individual variations in binding profiles may account for clinical differences. It has been shown that vascular endothelial growth factor is produced, expressed and secreted in the ovary and that it mediates vascular permeability in response to human chorionic gonadotropin in a time-dependent fashion. This effect may be blocked by a synthetic compound (SU5416) developed to inhibit its high-affinity receptor, kinase domain containing receptor signaling in different cancers by avoiding the initial phosphorylation of vascular endothelial growth factor receptor-2.

SUMMARY

Vascular endothelial growth factor is a promising molecule in the understanding of ovarian hyperstimulation syndrome. Future treatments should be directed to modulate or inhibit its action on the vascular wall.

Internal jugular vein thrombosis following in-vitro fertilization in a woman with protein S deficiency and heterozygosity for the prothrombin 3' UTR mutation, despite anticoagulation with heparin

We report the case of a 31-year-old woman with protein S deficiency and heterozygosity for the prothrombin 3' UTR mutation who developed an internal jugular vein thrombosis despite therapeutic anticoagulation with a low molecular weight heparin, following in-vitro fertilization. This case indicates that the stimulus to thrombosis in such women is intense and can occur despite apparent therapeutic anticoagulation. Close attention should, therefore, be paid to any women with a personal or family history of thrombosis and the potential thrombotic risks associated with assisted conception must be discussed.