Serum ferritin level is inversely related to number of previous pregnancy losses in women with recurrent pregnancy loss.

OBJECTIVE: To study whether low serum ferritin (s-ferritin) levels are associated with recurrent pregnancy loss (RPL), and whether low s-ferritin predicts the risk of another pregnancy loss or the ability to conceive. DESIGN: Cohort study. SETTING: Fertility clinic at a university hospital. PATIENT(S): Eighty-four women referred to the RPL Unit and 153 women of reproductive age with no known fertility problem. s-Ferritin levels were measured in serum samples taken before pregnancy attempt. INTERVENTION: None. MAIN OUTCOME MEASURE(S): s-Ferritin levels were correlated to pregnancy history, ability to conceive, and time to conception during the first 2 years after sampling. Furthermore, s-ferritin levels were correlated to outcome of the first pregnancy after referral for RPL. RESULT(S): Women with RPL had lower s-ferritin than the comparison group, 39.9 µg/L versus 62.2 µg/L, and had a higher prevalence of low iron stores (s-ferritin <30 µg/L), 35.7% versus 13.7%. We found an inverse relationship between s-ferritin level and number of pregnancy losses before referral. We did not find s-ferritin level to be associated with ability to conceive or time to pregnancy in either group. Nor did s-ferritin level predict the risk of losing the first pregnancy after referral for RPL. CONCLUSION(S): The inverse relationship between s-ferritin levels and previous pregnancy losses suggests that low s-ferritin is associated with a more severe reproductive disturbance in women with RPL. Whether low s-ferritin is causally related to RPL and if such women could benefit from iron supplementation to achieve a live birth warrants further investigation.

The donors perceived positive and negative effects of blood donation.

BACKGROUND: Occasionally blood donation has a negative influence on some donors, while others express feelings of increased energy or wellbeing after donation. Some donors even report symptoms such as headache or feelings of unease indicating "it is time to donate blood again." This study aims to determine symptoms and frequencies of blood donors experiencing positive and negative effects of blood donation, and study possible associations with sex, age, body mass index, smoking status, and hemoglobin level. STUDY DESIGN AND METHODS: We developed and validated a questionnaire with eight predefined physical and psychological symptoms related to blood donation using a 5-point Likert Scale. Participants in The Danish Blood Donor Study were asked to indicate if they experienced the present symptom prior to and/or after the donation. RESULTS: A total of 6,073 donors were included. Of the donors, 61% experienced one or more effects of blood donation. Positive effects were experienced by 18% of the donors, 29% experienced negative effects, and 14% experienced both. Most notable positive effects were alleviated headache (14%), feeling lighter (14%), and less tiredness (7%). Most notable negative effects were less energy (25%), more dizziness (22%), and more tiredness (21%). Logistic regression analysis revealed that positive effects were more likely among donors with higher BMI, older donors, and smokers. Negative effects were more likely among younger donors, donors with lower BMI, and among female donors. CONCLUSION: Analyses indicate that susceptibility to blood donation effects varies by BMI, sex, smoking status, and age, and therefore should be taken into consideration when informing donors about potential effects of blood donation.

Prevalence and correlation of cytokine-specific autoantibodies with epidemiological factors and C-reactive protein in 8,972 healthy individuals: Results from the Danish Blood Donor Study.

Natural cytokine-specific autoantibodies (c-aAb) have been measured in healthy and diseased individuals, and have been considered as both endogenous immune-regulators and pathogenic factors. Overall, the etiology and potential pathology of c-aAb are still undefined. To further characterize the sero-prevalence, predictors and consequences of high c-aAb levels, we performed the largest population-based study of c-aAb to date, using participants and epidemiological data from the Danish Blood Donor Study. Using a validated bead-based multiplex assay we assessed plasma levels of IL-1α, IL-6, IL-10, IFNα and GM-CSF-specific c-aAb in 8,972 healthy blood donors. Trace levels of at least one of the investigated c-aAb could be measured in 86% of the participants. The presence of high levels of potentially inhibitory c-aAb was generally associated with increasing age and male or female sex, depending on the c-aAb in question. A negative correlation between high levels of IL-6-specific c-aAb and plasma levels of C-reactive protein was observed, indicating cytokine-neutralizing levels of c-aAb in healthy blood donors. There was no substantial correlation between high levels of the five individual c-aAb investigated in this study. These data suggest that autoimmunity against endogenous cytokines is a relatively common phenomenon in healthy individuals, and that predictive factors for high, potentially neutralizing c-aAb levels vary depending on the cytokine in question, and may differ from predictors of general c-aAb presence.

Predictors of iron levels in 14,737 Danish blood donors: results from the Danish Blood Donor Study.

BACKGROUND: Dietary studies show a relationship between the intake of iron enhancers and inhibitors and iron stores in the general population. However, the impact of dietary factors on the iron stores of blood donors, whose iron status is affected by blood donations, is incompletely understood. STUDY DESIGN AND METHODS: In the Danish Blood Donor Study, we assessed the effect of blood donation frequency, physiologic factors, lifestyle and supplemental factors, and dietary factors on ferritin levels. We used multiple linear and logistic regression analyses stratified by sex and menopausal status. RESULTS: Among high-frequency donors (more than nine donations in the past 3 years), we found iron deficiency (ferritin below 15 ng/mL) in 9, 39, and 22% of men, premenopausal women, and postmenopausal women, respectively. The strongest predictors of iron deficiency were sex, menopausal status, the number of blood donations in a 3-year period, and the time since last donation. Other significant factors included weight, age, intensity of menstruation, iron tablets, vitamin pills, and consumption of meat and wine. CONCLUSION: The study confirms iron deficiency as an important problem, especially among menstruating women donating frequently. The risk of iron depletion was largely explained by sex, menopausal status, and donation frequency. Other factors, including dietary and supplemental iron intake, had a much weaker effect on the risk of iron depletion.