Effects of breastfeeding on weight loss and recovery of pregestational weight in adolescent and adult mothers.

BACKGROUND: Exclusive breastfeeding (EBF) in adolescent mothers has been associated with greater postpartum maternal weight loss. OBJECTIVE: To assess the associations between EBF and weight loss in adolescent and adult mothers and between EBF and weight and length gain of their children. METHODS: A cohort of 68 adolescent mothers (15 to 19 years), 64 adult mothers (20 to 29 years), and their infants were studied. Anthropometric measurements were performed at 15, 90, 180, and 365 days postpartum in the mothers and children. EBF was defined as consumption of human milk without supplementation of any type (water, juice, nonhuman milk, or food) for 4 months. RESULTS: Sixty-five percent of mothers sustained EBF for 4 months. There were no significant differences in the weight or length of the infants of adolescent and adult mothers at 365 days postpartum. Among infants of adult mothers, there was a significant difference between the weight gain of those were exclusively breastfed and those who were not exclusively breastfed (6,498 +/- 1,060 vs 6,096 +/- 1,035 g, p < .050) at 365 days postpartum, according to the parameters for weight gain and length established by the World Health Organization (WHO). Among both adult and adolescent mothers, those who practiced EBF lost more weight than those who did not practice EBF (-2.9 kg, 95% interquartile range, -5.7 to 0.8 kg, vs -1.8 kg 95% interquartile range -2.8 to 2.2 kg; p = .004). Gestational weight gain, duration of EBF, and recovery menstruation explained 21% of the variance (F = 28.184, p = .001) in change in postpartum maternal weight (in kilograms) from 0 to 365 days postpartum in all mothers. Pregestational weight, duration of EBF, and maternal age were factors that explained 14% (F = 22.759, p = .001) of the change in the weight and length of the infants from 0 to 365 days of life. CONCLUSIONS: EBF in adolescent and adult mothers influences postpartum weight loss and provides adequate infant growth in accordance with the WHO 2006 standards.

No changes in weight and body fat in lactating adolescent and adult women from Mexico.

OBJECTIVE: To evaluate changes in weight and body fat of Mexican adolescent compared to those of adult lactating women from the Northwest (NM) and Central (CM) regions of Mexico in the first trimester postpartum. METHODS: A prospective design was used to evaluate 41 exclusively breastfeeding women (21 adolescents and 20 adults) recruited 1-2 days after delivering a healthy singleton at the Hospital Infantil del Estado de Sonora (Northwest Mexico) and Instituto Nacional de Perinatología, in Mexico City. Socioeconomic status, height, body weight and composition, dietary intake, physical activity, and milk volume (quantified by deuterium dilution method) were measured at the 1st and 3rd month postpartum. RESULTS: Women did not lose weight throughout the first trimester postpartum. Mean postpartum weight retention at the end of the study was 3.8 kg. No differences in weight and body mass index (BMI) were found between adolescent and adult women in both periods. Energy and macronutrient intakes, physical activity and milk volume were similar between the two groups of women. In both periods, adolescents from the CM region had lower weight, BMI, and body fat than adolescents from the NM region (P<0.05). At the 3rd month, pregestational weight (P < 0.0001) was a predictor of BMI, and region (P < 0.05) and milk volume (P < 0.01) were associated with percentage of body fat. CONCLUSIONS: Exclusively breastfeeding for 3 months did not reduce weight or body fat in the Mexican population of this study. Efforts to avoid weight retention in the lactation period may contribute to prevent overweight and obesity in women.

[Adolescents do not lose bone mineral density postpartum: comparative study with adult women]. / Las adolescentes no pierden densidad mineral ósea en el posparto: estudio comparativo con adultas.

OBJECTIVE: To analyze the pattern of bone mineral density (BMD), serum concentrations of estradiol and calcium levels, dietary calcium, body mass index (BMI), and lactation in adolescents and adult women at 15, 90, and 365 postpartum days (ppd). MATERIAL AND METHODS: A prospective cohort study was conducted of 33 adolescents and 39 adult women. Anthropometric and dietetic evaluations were performed, as well as evaluations of bone mineral density in L2-L4 and femur neck. Estradiol concentrations and calcium serum levels were determined. RESULTS: L2-L4 BMD increased by 16% in adolescents, and 3% in adult women from day 15 to 365 ppd. While age was associated with this change (ß=13.779, EE=3.5, p=0.001), lactation was not (ß=-0.705, EE=0.647, p=0.283). The adult women had a higher L2-L4 BMD at 15, 90, and 635 ppd (1.151 vs 0.978 g/cm², 1.195 vs 1.070 g/cm², 1.195 vs 1.123 g/cm², respectively) (p<0.003). CONCLUSIONS: Adolescents' BMD increased three times more than that of adult women. For all women, BMD was dependent of age and independent of lactation.

[Adolescents increase to more gestational weight and fat than adults according to BMI pre-gestational]. / Las adolescentes aumentan más peso y grasa gestacional que las adultas, según IMC pregestacional.

INTRODUCTION: The excessive gestational weight gain predisposes to overweight and obesity postpartum, this becomes a worldwide public health problem. OBJECTIVE: To analyze gestational weight pattern and body fat in adolescents and adult women, to identify the group that would have major weight and body fat gain. MATERIAL AND METHODS: A prospective cohort study done in 64 adolescent < or = 18 years and 48 adult women. Anthropometric evaluation was realized, at 20, 24, 28, 32, 36 and 38 gestational weeks with weight and body fat percentage. Patients signed letter informed consent. RESULTS: In adolescents weight and BMI were smaller (p < 0.001), and their gestational fat gain was bigger than in the adult women (5.31 vs. 4.12 kg; p < 0.001). Pre-gestational BMI (beta = 0.459, EE = 0.089, p = 0.001), and age group (beta = - 1.400, EE = 0.735, p = 0.060) were associated to fat percentage variability. The adolescents with low weight and BMI > or = 85th percentile showed a greater gain of weight in respect to which is classified as normal weight (18.0 and 15.5 vs. 12.0 kg; p = 0.018). 54.7% of the adolescents and 64.6% of adults did gain excessive weight, more than the recommended according pre-gestational BMI. CONCLUSIONS: Age and pregestational BMI conditioned the body fat change. More than half of the patients included exceeded the recommended weight gain. The overweight or excessive weight gain adolescents have increased risk of postpartum retention weight than adult women in the same conditions.

Women with endometriosis improved their peripheral antioxidant markers after the application of a high antioxidant diet.

BACKGROUND: Oxidative stress has been identified in the peritoneal fluid and peripheral blood of women with endometriosis. However, there is little information on the antioxidant intake for this group of women. The objectives of this work were 1) to compare the antioxidant intake among women with and without endometriosis and 2) to design and apply a high antioxidant diet to evaluate its capacity to reduce oxidative stress markers and improve antioxidant markers in the peripheral blood of women with endometriosis. METHODS: Women with (WEN, n = 83) and without endometriosis (WWE, n = 80) were interviewed using a Food Frequency Questionnaire to compare their antioxidant intake (of vitamins and minerals). Then, the WEN participated in the application of a control (n = 35) and high antioxidant diet (n = 37) for four months. The high antioxidant diet (HAD) guaranteed the intake of 150% of the suggested daily intake of vitamin A (1050 microg retinol equivalents), 660% of the recommended daily intake (RDI) of vitamin C (500 mg) and 133% of the RDI of vitamin E (20 mg). Oxidative stress and antioxidant markers (vitamins and antioxidant enzymatic activity) were determined in plasma every month. RESULTS: Comparison of antioxidant intake between WWE and WEN showed a lower intake of vitamins A, C, E, zinc, and copper by WEN (p < 0.05, Mann Whitney Rank test). The selenium intake was not statistically different between groups. During the study, the comparison of the 24-hour recalls between groups showed a higher intake of the three vitamins in the HAD group. An increase in the vitamin concentrations (serum retinol, alpha-tocopherol, leukocyte and plasma ascorbate) and antioxidant enzyme activity (superoxide dismutase and glutathione peroxidase) as well as a decrease in oxidative stress markers (malondialdehyde and lipid hydroperoxides) were observed in the HAD group after two months of intervention. These phenomena were not observed in the control group. CONCLUSION: WEN had a lower intake of antioxidants in comparison to WWE. Peripheral oxidative stress markers diminished, and antioxidant markers were enhanced, in WEN after the application of the HAD.

Searching for alternative methods of diagnosing gestational diabetes mellitus in a Mexican urban population.

BACKGROUND: The aim of the study was to determine whether a predictive value for the diagnosis of gestational diabetes mellitus (GDM) could be established using different glucose screening test thresholds in Mexican urban pregnant women. MATERIAL/METHODS: A group of 635 pregnant women (12-33 weeks of gestation) with serum glucose screening values of > or = 7.2 mmol (> or = 130 mg/dl) were evaluated with a 100-g 3-h oral glucose tolerance test (OGTT). The positive predictive values (PPVs) for serum glucose screening values of > or = 7.2 mmol to > or = 11.1 mmol (> or = 130 to > or = 200 mg/dl), age, and pregestational BMI were calculated. RESULTS: Of the women, 304 (47.8%) had a normal OGTT, 126 (19.8%) had impaired glucose tolerance, and 205 (32.3%) had GDM. A serum glucose screening value of > or = 9.4 mmol (> or = 170 mg/dl) had a positive predictive value (PPV) of 0.85 and the relative risk for GDM was 6.62 (95%CI: 4.40-9.97, p=0.001). Omission of the 3-h value during OGTT yielded a sensitivity of 91.2% (187/205). CONCLUSIONS: In this group of Mexican urban pregnant women, a serum glucose screening value of > or = 9.4 mmol (> or = 170 mg/dl) had a PPV of 85%. An algorithm is proposed to reduce the number of OGTTs performed in pregnant women attending prenatal care by 36.2%.

High dosage of ascorbic acid and alpha-tocopherol is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.

AIM: To determine the useful dosage of ascorbic acid and alpha-tocopherol against oxidative stress and DNA damage in the elderly. METHODS: A double-blind controlled clinical assay carried out in a sample of 66 healthy subjects divided into three age-paired random groups with 22 subjects in each group. Group A received placebo and group B was administered 500 mg of ascorbic acid and 400 IU of alpha-tocopherol, whereas group C received 1,000 mg of ascorbic acid and 400 IU of alpha-tocopherol for a 6-month period. The following measurements were performed before and after the 6-month treatment period: thiobarbituric acid reactive substances (TBARS); total antioxidant status (TAS); superoxide dismutase (SOD), and glutation peroxidase (GPx) and DNA damage by comet assay. RESULTS: After 6 months, group B subjects exhibited an increase in SOD and GPx enzyme levels; however, this was not statistically significant (p > 0.05). Likewise, TBARS and TAS concentrations remained unchanged (p > 0.05). In addition, in group C the decrease in TBARS and increase in SOD, GPx, and TAS were not statistically significant (p > 0.05). Similarly, average DNA migration showed no significant differences with high-dosage ascorbic acid and alpha-tocopherol. CONCLUSION: These findings suggest that administration of 1,000 mg of ascorbic acid plus 400 IU of alpha-tocopherol for 6 months is not useful for diminishing oxidative stress and DNA damage in healthy elderly adults.

[Scientific rationality, causality and meta-analyses of clinical trials]. / Racionalidad científica, causalidad y metaanálisis de ensayos clínicos.

Currently, the challenge is to analyze and synthesize as much information as possible in order to make quick, correct decisions. Systematic reviews and meta-analysis have quickly arisen in the health field because they allow researchers to congregate studies of similar characteristics to generate estimators that describe the risk or benefit of practices related to health problems. To understand and attach the appropriate importance to meta-analyses, it is necessary to consider the rationale of the theoretical framework, the methodological criteria, and the possible causal relationship between exposure and outcome, besides contextualizing the information. This paper briefly explores scientific rationality and its application in causal theory within an epidemiological framework, to set the basis that allows decision-makers and health professionals to evaluate the appropriateness and validity of conclusions derived from this type of analyses.

Risk for postpartum depression, breastfeeding practices, and mammary gland permeability.

In a cross-sectional study, 163 breastfeeding women completed the Edinburgh Postnatal Depression Scale (EPDS), a questionnaire on demographics and infant feeding and hand-expressed breast milk for Na and K quantification, between 2 and 12 weeks postpartum. Forty women (24.5%) had an EPDS score compatible with the risk of a depressive episode, and 63 (41%) did not feel confident about breastfeeding. These 2 variables were significantly correlated to each other and individually correlated to breastfeeding exclusiveness. Weeks postpartum was correlated to breastfeeding exclusiveness and Na:K in milk (all P < .001). A logistic regression model showed that supplementation increased the risk of high Na:K in milk by 209%, whereas a longer time postpartum lowered the risk for mammary gland permeability. This study suggests that postpartum depression and low breastfeeding confidence, which may be present concomitantly, are associated with increased mammary gland permeability, only to the extent in which depression dissuades the mother from exclusive breastfeeding.

Gestational weight gain as predicted by pregestational body mass index and gestational age in Mexican women.

OBJECTIVE: To develop a reference pattern to evaluate gestational weight according to pregestational body mass index (BMI) and gestational age, using current longitudinal information from healthy pregnant women. SUBJECTS AND METHODS: We followed 438 women with singleton pregnancies between weeks 16 and 36 of pregnancy Women were excluded if they developed pathologic conditions during gestation, delivered malformed or dead fetuses, or delivered babies with a birthweight of less than 2500 or more than 4200 g or with a gestational age of less than 37 or more than 41 weeks. Weight, biochemical indicators, and clinical indicators were recorded every 4 weeks throughout the pregnancy. Data were analyzed by sequential regressions. RESULTS: Four equations for maternal predicted weight across categories of pregestational BMI (underweight, normal, overweight, and obese) and gestational ages were developed and synthesized in a table of reference values. CONCLUSIONS: Optimal weight and weight gain during pregnancy can be estimated with our equations, which are corrected for pregestational BMI and gestational age.

Dialyzability of minerals in corn masa gruel (atole) fortified with different iron compounds: effects of ascorbic acid, disodium EDTA, and phytic acid.

BACKGROUND: Lime-treated corn gruel (atole) is a common weaning food in iron-deficient populations, especially in Mexico and Central America, and is a potential vehicle for fortification with iron. OBJECTIVE: The objective of this study was to screen promising iron compounds for use in the fortification of atole, using in vitro enzymatic digestion-dialysis techniques, while also considering their response to known iron absorption enhancers and inhibitors. METHODS: Atole, unaltered or preincubated with phytase, was fortified with iron (10 mg/L) from ferrous sulfate, ferrous bisglycinate, or ferrous fumarate, or with ferric chloride, ferric ammonium citrate, or ferric sodium ethylenediaminetetraacetic acid (NaFeEDTA), and submitted to in vitro digestion. Dialysis of calcium, copper, iron, phosphorus, and zinc (analyzed by inductively coupled plasma atomic emission spectrometry) was measured when atole was fortified with iron compounds alone or together with ascorbic acid or disodium ethylenediaminetetraacetic acid (Na2EDTA). RESULTS: Iron dialyzability was higher with NaFeEDTA (p < .05) than with all other iron compounds, which did not differ among themselves in iron dialyzability. Addition of ascorbic acid had no significant effect on iron dialysis, whereas Na2EDTA enhanced iron dialyzability by 7 to 10 times in unaltered atole and 15 to 20 times in phytase-preincubated atole (p < .05). Addition of Na2EDTA always increased intrinsic zinc dialyzability, and most of the time this increase was significant. Phytase pretreatment generally increased mineral dialysis. CONCLUSIONS: Adding EDTA (either as NaFeEDTA or as Na2EDTA) to atole can increase the dialyzability of ferrous and ferric iron compounds and enhance the dialyzability of intrinsic zinc without any negative effects on calcium, phosphorus, or copper dialysis.

Weekly iron as a safe alternative to daily supplementation for nonanemic pregnant women.

BACKGROUND: We undertook this study to compare the effectiveness and safety of antenatal daily and weekly supplementation with iron, folic acid, and vitamin B(12) in healthy, pregnant women who were not anemic at gestational week 20. METHODS: Women with singleton pregnancies and blood hemoglobin (Hb) >115 g/L at gestational week 20 (equivalent to 105 g/L at sea level) were randomly assigned to two groups, one consuming one tablet containing 60 mg iron, 200 mug folic acid and 1 mug vitamin B(12) daily (DS, n = 56); the other consuming two tablets once weekly (WS, n = 60). Blood Hb and serum ferritin concentrations were measured every 4 weeks from weeks 20 to 36, and pregnancy outcomes were evaluated. RESULTS: Mild anemia and hypoferritinemia throughout pregnancy occurred less frequently in DS than WS. None of the 116 women had Hb concentrations <103 g/L at any evaluation point. In contrast, hemoconcentration (Hb >145 g/L) from gestational week 28 onwards occurred in 11% in DS and 2% in WS. We observed ex post facto that hemoconcentration at gestational week 28 was associated with a significantly higher relative risk of low birth weight (RR 6.23, 95% CI 1.46-26.57) and premature delivery (RR 7.78, 95% CI 1.45-24.74). CONCLUSIONS: In women who were nonanemic at gestational week 20, both schemes (DS and WS) prevented the occurrence of Hb levels <100 g/L. DS women had a higher incidence of hemoconcentration. Hemoconcentration was associated with increased risk of low birth weight and premature delivery.

Vitamin C supplementation to prevent premature rupture of the chorioamniotic membranes: a randomized trial.

BACKGROUND: Vitamin C is involved in the synthesis and degradation of collagen and is important for maintenance of the chorioamniotic membranes. Inadequate availability of ascorbic acid during pregnancy has been proposed as a risk factor for premature rupture of the chorioamniotic membranes (PROM). OBJECTIVE: The objective of the study was to evaluate the effectiveness of 100 mg vitamin C/d in preventing PROM. DESIGN: A controlled double-blind trial was performed. Pregnant women (n = 126) in their 20th wk of gestation were invited; 120 accepted and were randomly assigned to 2 groups (100 mg vitamin C/d or placebo). Every 4 wk, plasma and leukocyte vitamin C concentrations were measured, and each subject was evaluated for cervicovaginal infection. The incidence of PROM was recorded for each group as an indicator of the protective effect of vitamin C supplementation. RESULTS: One hundred nine patients finished the study. Mean plasma vitamin C concentrations decreased significantly throughout the pregnancy in both groups (P = 0.001), and there were no significant differences between groups. Between weeks 20 and 36, mean leukocyte vitamin C concentrations decreased from 17.5 to 15.23 microg/10(8) cells in the placebo group and increased from 17.26 to 22.17 microg/10(8) cells in the supplemented group (within- and between-group differences: P = 0.001). The incidence of PROM was 14 per 57 pregnancies (24.5%) in the placebo group and 4 per 52 pregnancies (7.69%) in the supplemented group (relative risk: 0.26; 95% CI: 0.078, 0.837). CONCLUSION: Daily supplementation with 100 mg vitamin C after 20 wk of gestation effectively lessens the incidence of PROM.

Twin pregnancies: eating for three? Maternal nutrition update.

The incidence of multifetal pregnancies has increased, mainly because of assisted reproduction treatments. This trend is reflected in increased maternal and neonatal morbidity and mortality. While the optimum maternal nutrition and weight gain patterns for singleton pregnancies is well documented, there is a paucity of information for twin pregnancies. Although it is assumed that optimum nutritional requirements and weight gains would be greater for twin than for singleton gestations, research is needed to establish the optima. This article is a collation of available recommendations for maternal nutrition and weight gain patterns in twin pregnancies.

[Use of maternal-infant preventative health services in a group of Mexican women]. / Uso de servicios preventivos de salud materno-infantil en un grupo de mujeres mexicanas.

OBJECTIVE: To identify factors that promote the use of health services in a group of women of reproductive age from a gender perspective. METHOD: A retrospective and analytical study based on a questionnaire on maternal infant mortality of fifty women (users and non-users of preventative health services) in health centers in Mexico City was carried out. A conglomerate analysis of averages was executed. An analysis of variance was done to evaluate the fitness of the model. The statistical analysis was done using the SPSS statistical package version 12.0. RESULTS: Planning of the last pregnancy, including having had sexual relations with the intention of procreation, was the behavior that showed a significant difference (p=0.001) between users and non-users of preventative health services. Social-demographic characteristics (age, education level, martial status, woman's occupation) did not reveal any differences between the two groups. CONCLUSION: Reproductive planning could be an indicator of preventative behavior in the use of preventative health services.

[Bases to determine the dose of vitamin C in pregnancy]. / Bases para estimar las necesidades de vitamina C en la gestación.

OBJECTIVE: Determine the dose of Vitamin C able to maintain a leukocyte Vitamin C concentration of > or =18 microg/10(8) cells, in pregnant women with 28 to 32 weeks of gestation, in order to compile a database to estimate the daily recommended intake (DRI) during pregnancy. METHODOLOGY: Stage 1: acute supplementation study. A group of 10 healthy women in late first and early second trimester pregnancy were supplemented with 0 to 200 mg vitamin C/day during one week each. Stage 2: a randomized double blind study (placebo vs. vitamin C [100 mg/d]) was carried out with 52 women studied from week 20 to week 32 of pregnancy. Their plasma and leukocyte vitamin C concentrations were measured every 4 weeks to evaluate the previously established supplementation dose. RESULTS: Stage 1: with the 100 mg/day dose, leukocyte vitamin C saturation was reached without increasing urinary excretion. Stage 2: leukocyte concentration of vitamin C decreased throughout pregnancy in women receiving placebo, while supplemented women maintained their concentrations > or =18 microg/10(8) cells. CONCLUSION: A 100 mg/day dose of vitamin C during the second half of pregnancy keeps leukocyte storage and could be useful to establish the DRI of Vitamin C during pregnancy.

Increased ERG a- and b-wave amplitudes in 7- to 10-year-old children resulting from prenatal lead exposure.

PURPOSE: To determine the dose-response relationship between blood lead concentration ([PbB]) and scotopic ERG amplitude in 7- to 10-year-old children with lifetime lead exposure. METHODS: Full-field flash scotopic ERGs were recorded over a 4-log-unit range in 45 dark-adapted children with normal visual acuity. [PbB] was measured throughout pregnancy and postnatal development, and the subjects' [PbB] levels were grouped at each age by tertiles. RESULTS: The median [PbB] during pregnancy was, from lowest to highest tertile, 2.5 to 5.0, 7.5 to 9.0, and 14.0 to 16.5 microg/dL, and after birth was 4.0 to 8.0, 6.0 to 14.5, and 7.5 to 21.0 microg/dL. Only maternal [PbB] at 12 weeks of pregnancy showed a significant dose-response relationship with the ERG measures, so that with increasing [PbB] there were significant increases in leading-edge a-wave amplitude, peak a-wave amplitude, and b-wave amplitude and sensitivity, with no changes in implicit times. Data analyses showed that children whose mothers had [PbB] of 10.5 microg/dL or more at 12 weeks of pregnancy had relatively increased a- and b-waves. CONCLUSIONS: Lead exposure during the first trimester of pregnancy produces dose-dependent increases in scotopic a- and b-wave amplitudes in 7- to 10-year-old children. The results suggest that the increases in a- and b-wave amplitudes originate from rods; however, the increased b-wave amplitude and sensitivity may also originate in the inner retina. These alterations occurred at maternal [PbB] at or below currently accepted safe levels. These novel findings reveal that the developing retina is a sensitive target for lead and suggest that lead-exposed children be examined for possible future visual system deficits.

Measurement of deuterium oxide by infrared spectroscopy and isotope ratio mass spectrometry for quantifying daily milk intake in breastfed infants and maternal body fat.

Measurements of deuterium oxide concentrations (DOC) in saliva by infrared spectroscopy (IRS) and isotope ratio mass spectrometry (IRMS) were compared for the calculation of infants' milk intake and maternal body fat. Deuterium oxide (30 g) was given to the mother. DOC by IRS and IRMS were 340 +/- 209 and 345 +/- 202 ppm. The mean difference between both methods (4.62 +/- 76.3) was not different from zero (p = .57). Bland and Altman analysis showed no significant overall bias (r = 0.10; p = .33), but dispersion within the limits of agreement. The mean milk intake in the infants' by IRS and IRMS were 624 +/- 296 g/day and 634 +/- 327 g/day (p = .642) and the mothers' mean body fat were 31.3 +/- 12% and 31.5 +/- 13% (p = .755). The results appear to be the same for milk intake and body fat by the two methods and no evidence of bias was found.

Prevalence of nutritional deficiencies in Mexican adolescent women with early and late prenatal care.

The objective was to evaluate the prevalence of specific nutritional deficiencies in a group of pregnant adolescents according to the gestational age when they started to receive prenatal care. A group of 163 pregnant adolescents that attended the Instituto Nacional de Perinatología (Mexico City) for the first time to receive prenatal care was evaluated. An anthropometrical evaluation was performed and a blood sample taken to determine hemoglobin, ferritin, erythrocyte folate and plasma zinc to all cases. The mean age was 15 years (11 to 17 years). The mean gestational age when starting prenatal care was 27 +/- 7 gestation weeks and most of them tended to have low weight (97 +/- 12% expected weight for height and gestational age). Eight of every ten adolescents had anemia and iron deficiency. Late prenatal care (> or = 25 weeks) was associated with the risk of presenting anemia OR 5.11 (CI 95% 2.4-10.7) iron deficiency (OR 3.5; CI 95% 1.7 to 7.1) and zinc deficiency (OR 2.9; CI 95% 1.1 a 7.6). In relation to folate deficiency, the opposite effect was observed (OR 0.10; CI 95% 0.02 a 0.48). Lack of opportune prenatal care was associated with the presence of iron and zinc depletion. Probably iron deficiency contributes to an erythrocyte folate accumulation.

Antenatal iron supplements consumed daily produce oxidative stress in contrast to weekly supplementation in Mexican non-anemic women.

UNLABELLED: Universal prenatal daily supplementation with iron (60-120mg iron) plus folic acid (0.4mg), as recommended by INACG/WHO/UNICEF, prevents anemia where iron deficiency is prevalent but may be excessive for non-anemic women. Weekly supplementation with 120mg iron plus various amounts of folic acid similarly prevents significant anemia. OBJECTIVE: Determine, in non-anemic pregnant women, if oxidative stress is produced by recommended daily or weekly supplementation schemes. PROCEDURE: 100 non-anemic pregnant women, 30% iron-deficient at week 20, were randomly supplemented daily followed by weekly, each for 8 weeks, or in reversed order. RESULTS: With daily supplementation thio-barbituric-acid-reacting-substances (TBARS) increased significantly and high serum ferritin, iron, and excessively elevated hemoglobin occurred near term. During weekly supplementation significant anemia and high iron parameters were prevented, and elevated TBARS declined. CONCLUSION: In non-anemic pregnant women both schemes prevented significant anemia. Oxidative stress occurred only during daily supplementation periods. Weekly supplementation appears safer.