Folic acid supplementation during the preconception period: A systematic review and meta-analysis.

Guidelines recommend that women take folic acid supplements in the preconception period to prevent neural tube defects (NTDs) in their offspring. Estimates of adherence to this recommendation across different countries worldwide have not been synthesized. Medline, CINAHL, and EMBASE were systematically searched to identify studies reporting the prevalence of preconception folic acid supplementation. Pooled prevalence estimates for each country (where data were available) were calculated; and differences based on demographic, methodological, and study quality characteristics were examined. Of 3372 titles and abstracts screened, 722 full-texts were reviewed and 105 articles that reported 106 estimates of preconception folic acid supplementation in 34 countries were included. Pooled prevalence estimates were 32-51% in North America, 9-78% in Europe, 21-46% in Asia, 4-34% in the Middle East, 32-39% in Australia/New Zealand, and 0% in Africa. No South American studies were identified. Higher supplementation prevalence was observed in studies that had more highly educated samples, were conducted in fertility clinics, and assessed folic acid use via self-report. Of note, only 32% and 28% of studies reported timing of folic acid use and adherence to folic acid, respectively. Preconception folic acid supplementation is highly variable worldwide and many women may not achieve sufficient folate levels to prevent NTDs. To better understand non-adherence, recommendations for future research include: more explicit reporting of methodology, more detailed assessment of folic acid use, assessment of variables potentially relevant to folic acid use, and surveillance of folic acid use in a greater diversity of countries, especially in the developing world.

The value of middle phalangeal hair as an anthropometric marker: A review of the literature.

Middle phalangeal hair (MPH) is a trait frequently examined in anthropological studies throughout the 20th century. MPH is found on the back of the middle segment of the fingers, excluding the thumb. Typically, researchers examined the presence and absence of hair in various populations, and described it in terms of age, ancestry, and sex. Recently MPH has been examined as a potential anthropometric indicator of: androgen levels, androgen-related side effects in women, gene homozygosity, and disease resistance. Given the potential value of this marker, the present paper provides a comprehensive overview of MPH and its associated characteristics (i.e., ethnicity, sex, age, and hormonal variations) and presents new data on the reliability of MPH assessment. Findings suggest that ethnicity, sex, and age need to be controlled in any studies examining MPH and its relationship with other variables. Two measures of MPH (i.e., presence/absence of MPH and actual hair count) are both acceptable to use in MPH assessment; and the use of a hand lens to examine MPH provides high reliability when MPH is assessed by expert raters. However, researchers should avoid participant self-assessment. Future avenues for research are suggested (e.g., measurement issues and studies on hormonal correlates in women). MPH could be useful in research or for clinical purposes as a possible non-invasive indicator of hormone levels or hormonal sensitivity, or of predisposition toward androgen-related or gene-homozygosity-related health issues or behaviors.

Do oral contraceptives act as mood stabilizers? Evidence of positive affect stabilization.

Previous research has suggested that oral contraceptives (OCs) may provide a stabilizing effect on affect. The present study examined whether OC users and nonusers differ in their affect reactivity in response to four laboratory mood induction procedures. A sample of 107 undergraduate students (40 OC users, 36 nonusers, and 31 men) completed the Positive and Negative Affect Schedule (PANAS) before and after completing a series of four mood-induction procedures (i.e., positive affect, jealousy, social ostracism, and parental feelings affect inductions). OC users experienced a blunted positive affect response to the tasks when compared with nonusers and men. Women who used OCs for less than two years showed the lowest positive affect reactivity. The groups did not differ in terms of negative affect reactivity. The results suggest that hormonal contraceptives may reduce the degree of positive affect change that women experience in response to environmental events. Possible mechanisms for an OC-induced positive affect stabilization effect are discussed.

Effects of oral contraceptives on daily self-ratings of positive and negative affect.

OBJECTIVES: The relationship between affect and duration of oral contraceptive (OC) use was investigated. METHOD: Ninety-six women (17 first-time OC users, 34 long-time users, and 45 never-users) completed the Positive and Negative Affect Schedule (PANAS) and the Menstrual Distress Questionnaire (MDQ) daily for 35 days. This study was the first to examine positive affect variability; and personal family psychiatric history; and to compare early-, late-, and never-users of OCs. RESULTS: Triphasic users experienced greater variability in positive affect across the cycle, likely due to the variable hormone levels. Withdrawal of a constant level of hormones (monophasics) during early use was associated with greater variability in positive affect than withdrawal of changing hormonal levels (triphasics). Furthermore, personal and family psychiatric history may mediate an effect of OCs on negative affect variability. CONCLUSIONS: OCs and, therefore, hormones can alter day-to-day affect variability. Four variables are associated with this effect: duration of use, OC type, personal psychiatric history, and family psychiatric history.

Does body fat protect against negative moods in women?

An examination of the relationship between body mass index (BMI) and negative mood revealed an inverse relationship between BMI and negative mood symptoms (i.e., depression and negative affect scale scores) in women who were not taking oral contraceptives. The strength of the negative correlations between BMI and negative affect was uniformly higher on days of the menstrual cycle when estrogen levels are expected to be highest. Two interpretations are suggested. Given the positive relationship between estrogen levels and body fat, estrogen may have an effect on both body fat storage and negative affect. The cyclical release of estrogen may also have activational effects on negative affect. These findings have implications for common beliefs about the relationship between body size and emotional well-being, and provide converging evidence for the role of hormones in the regulation of mood.