Menstruation does not cause anemia: Endometrial thickness correlates positively with erythrocyte count and hemoglobin concentration in premenopausal women

Abstract

Menstruation has often been cited as a risk factor for iron-deficiency anemia. This study tested whether normal, premenopausal women's luteal endometrial thickness (ET) was associated with their red blood cell count (RBC) and hemoglobin concentrations (Hg), and therefore whether a high ET put women at risk for anemia. Endometrial thickness can be considered a reasonable proxy for menstrual blood loss in normal women. Twenty-six healthy women from the Mogielica Human Ecology Study Site in Poland, aged 20-40 years (29 +/- 5.3 years, mean +/- SD), were selected. Subjects' ET was measured by transvaginal ultrasound in the luteal phase of the menstrual cycle, and their red blood cell count and hemoglobin concentrations were measured by fasting morning blood samples. Controlling for day of ET measurement, RBC and Hg were positively correlated with ET (r(2) = 0.24, P = 0.05; r(2) = 0.25, P = 0.04, respectively). We propose that, contrary to popular understanding, a thicker endometrium suggests greater iron reserves, rather than greater risk for anemia, in healthy women.

Iron Status and Reproduction in US Women: National Health and Nutrition Examination Survey, 1999-2006

“…Menstrual blood loss has been associated with poorer indicators of iron status [16]–[18], although this perspective is controversial [19]. Fittingly, the use of hormonal contraceptive, which is generally associated with lighter menstrual periods, is associated with better indicators of iron status than in women who do not use hormonal contraceptives [10], [17].…”

Lower hemoglobin levels in first time mothers from Cebu, Philippines

“…The length of lactation amenorrhea from prior births was unavailable; among currently lactating mothers, 61.6% had resumed menstruation with an average amenorrhea length of 16.3 6 11.6 weeks ( Table 1). The resumption of menstruation was neither a significant predictor of hemoglobin nor an increased risk of maternal anemia in this sample; this is not surprising given emerging data suggesting that menstruation is not a major risk factor for anemia (Clancy et al, 2006).…”

“…Sear (2007) and Clancy et al, (2006) have shown improved reproductive condition, including earlier time to conception and increased endometrium thickness linked with higher maternal hemoglobin. However, this may not explain the variation in parity seen in this population.…”

“…For example, compared to reproductively cycling women, iron requirements are elevated during pregnancy but decreased during lactation (Milman, 2011;Piccano, 2003). The decrease in iron requirements is thought to reflect both the low levels of iron reported in human milk, 0.3-0.6 mg/100 ml (Dorea, 2001) and/or protective effects of lactational amenorrhea on maternal iron status, although both have been recently debated (Clancy et al, 2006;Picciano et al, 2003). There is also evidence that iron absorption is upregulated in lactating women (Picciano, 2003;Kalkwarf and Harrast, 1998), despite the lower iron requirements associated with lactation.…”

Iron Deficiency in Women

“…Your sense of taste seems to have been modified 13 8. Your nails become brittle and misshapen 14 9. Disruptive concentration -inability to focus on something for a protracted period 15 10.…”