Female reproductive history and the skeleton-a review

Osteoporosis International, 2012

The association between lactation and bone size and strength was studied in 145 women 16 to 20 years after their last parturition. Longer cumulative duration of lactation was associated with larger bone size and strength later in life. Introduction Pregnancy and lactation have no permanent negative effect on maternal bone mineral density but may positively affect bone structure in the long term. We hypothesized that long lactation promotes periosteal bone apposition and hence increasing maternal bone strength. Methods Body composition, bone area, bone mineral content, and areal bone mineral density of whole body and left proximal femur were assessed using DXA, and cross-sectional area and volumetric bone mineral density of the left tibia shaft were measured by pQCT in 145 women (mean age 48 years, range 36-60 years) 16 to 20 years after their last parturition. Hip (HSI) and tibia strength indexes (TBSI) were calculated. Medical history and lifestyle factors including breastfeeding patterns and durations were collected via a self-administered questionnaire. Weight change during each pregnancy was collected from personal maternity tracking records. Results Sixteen to 20 years after the last parturition, women who had breastfed in total more than 33 months in their life, regardless of the number of children, had greater bone strength estimates of the hip (HSI=1.92 vs. 1.61) and the tibia (TBSI= 5,507 vs. 4,705) owing to their greater bone size than mothers who had breastfed less than 12 months (p<0.05 for all). The differences in bone strength estimates were independent of body height and weight, menopause status, use of hormone replacement therapy, and present leisure time physical activity level. Conclusion Breastfeeding is beneficial to maternal bone strength in the long run.

Journal of Menopausal Medicine, 2016

Objectives: This study was done to determine the effect of multiparity and prolonged lactation on bone mineral density (BMD). Methods: This cross-sectional study included 196 perimenopausal and postmenopausal women aged 40 to 60 years old. Age, body mass index (BMI), menopausal status, duration of menopause, parity and total duration of lactation, nutritional history were recorded. Lumbar spine (LS; L2-L4) and femur neck (FN) BMD were measured using dual energy X-ray absorptiometry. Correlation of parity and lactation with BMD were investigated using multiple regression analysis. Results: Parity was inversely correlated to BMD for LS (β = -0.266, P = 0.001) and FN (β = -0.380, P = 0.000). This relation remained significant even after adjusting for age, BMI and duration of menopause. Duration of lactation was inversely correlated with BMD for LS (β = -0.271, P = 0.001) but no for FN (β = -0.124, P = 0.130). Conclusions: Multiparity and prolonged lactation have negative impact on BMD especially with in a socioeconomic group whose nutritional intake is borderline. Our data support that parity and duration of lactation can be associated with future osteoporosis. (J Menopausal Med 2016;22:161-166

Journal of International Medical Research, 2010

This study investigated the effect of the number of pregnancies on bone mineral density (BMD) in 320 post-menopausal women aged between 49 and 64 years. Cases were selected from people with similar lifestyles and stratified into five groups according to the number of pregnancies. Each group was divided into two subgroups according to the duration of the menopause (3-5 years versus 6-10 years). Lumbar (L2-L4) and femoral neck BMD were measured by dual-energy X-ray absorptiometry and T-score values were used in the statistical evaluation. No significant difference was found between the number of pregnancies and BMD within each group based on the same menopause duration, but a significant correlation was found in most groups based on menopause duration: T-scores decreased as menopause duration increased. Changes in BMD are likely to be related to menopause duration, rather than the number of pregnancies.

Maturitas, 2014

Objectives: Pregnancy and lactation have been associated with decline in bone mineral density (BMD). It is not clear if there is a full recovery of BMD to baseline. This study sought to determine if pregnancy or breast-feeding or both have a cumulative effect on BMD in premenopausal and early postmenopausal women. Study design: We performed single-center cohort analysis. Five hundred women aged 35-55 years underwent routine BMD screening from February to July 2011 at a tertiary medical center. Patients were questioned about number of total full-term deliveries and duration of breast-feeding and completed a background questionnaire on menarche and menopause, smoking, dairy product consumption, and weekly physical exercise. Weight and height were measured. Dual-energy X-ray absorptiometry was used to measure spinal, dual femoral neck, and total hip BMD. Main outcome measures: Associations between background characteristics and BMD values were analyzed. Results: Sixty percent of the women were premenopausal. Mean number of deliveries was 2.5 and mean duration of breast-feeding was 9.12 months. On univariate analysis, BMD values were negatively correlated with patient age (p = 0.006) and number of births (p = 0.013), and positively correlated with body mass index (p < 0.001). On multiple (adjusted) logistic regression analysis, prolonged breast-feeding duration, but not number of deliveries, was significantly correlated to a low BMD (p = 0.008). An effect was noted only in postmenopausal women. The spine was the most common site of BMD decrease. Conclusions: Prolonged breast-feeding may have a deleterious long-term effect on BMD and may contribute to increased risk of osteoporosis later in life.

BMC Women's Health, 2009

Background: Studies conducted in Western countries have shown that bone loss associated with pregnancy and breast-feeding is recovered after weaning. However, it is not clear whether recovery takes place after repeated pregnancies followed by prolonged periods of breast-feeding; especially in developing countries where nutritional intake is comparatively low. This study was designed to examine the effects of multiparity and prolonged breast-feeding on maternal bone mineral density (BMD) in a community-based sample of 210 Sri Lankan women, aged between 46 and 98 years. Methods: BMD of the lumbar spine (L 2 -L 4 ) and femoral neck were measured by dual-energy Xray absorptiometry. Reproductive history was recorded by using a questionnaire. Women were, first, divided into groups according to parity (nulliparous, 1-2, 3-4, and 5 or more children), and BMDs in different groups were compared, initially unadjusted and then adjusted for age. Same subjects were subdivided, again, according to the total duration of breast-feeding (0, 1-48, 49-96, and 97 months or more) and similar analysis was carried out. Results: Women who had 5 or more children and women who had breast-fed for 97 months or more were older than the other women (p < 0.01) but no differences in height, weight or BMI were observed among the groups. Age adjusted BMD at lumbar spine and femoral neck BMDs of women grouped according to parity were not significantly different. Neither was there any difference between lumbar spine or femoral neck BMD in groups based on duration of breast-feeding. From this population-based study conducted in a developing country, we infer that history of multiparity or prolonged breast-feeding has no detrimental effects on maternal BMD in post-menopausal age.

2003

in the one-to-two-parity group, spine BMD values appeared to be significantly higher than those of the more-than-fiveparity group (p Ͻ 0.05). Significant correlations were found between the number of pregnancies and BMD values for the spine (r ϭ Ϫ0.23; P Ͻ 0.01), trochanter (r ϭ Ϫ0.16; P Ͻ 0.01), and Ward's triangle (r ϭ Ϫ0.14; P Ͻ 0.05), with no significant correlation for femur neck BMD (r ϭ Ϫ0.08; P Ͼ 0.05) values. In conclusion, the present study suggests that the number of pregnancies has an effect on the BMD values and that this situation shows a variation in different age groups. In addition, our study indicates that there is a significant correlation between the number of pregnancies and the spine, trochanter, and Ward's triangle BMD, but there is no correlation for the femur neck BMD.

Türk Osteoporoz Dergisi, 2012

To determine the effects of reproductive factors on bone mineral density (BMD) in postmenopausal women. Materials and Methods: A total of 1196 postmenopausal women with BMD (g/cm 2) measurements at lumbar vertebra (LS) and femur neck (FN) were enrolled. Demographic, reproductive characteristics and Body Mass Index (BMI) of patients were defined. In order to define BMD related factors, multiple regression analysis was employed. Results: Main results were as follows: mean age= 59.97±8.56 yrs; weight= 73.49±13.06 kg; BMI= 29.25±5.22kg/m², age of menarche= 14.00±1.64 yrs; number of deliveries 4.22±2.09; total breastfeeding duration= 60.77±38.80 months; number of breastfeeding per day= 8.23±3.91; menopausal age= 47.12±4.22 yrs; duration of menopause= 12.80±9.10 yrs; LS BMD= 0.993±0.171 gr/cm2; FN BMD 0.844±0.14 gr/cm2. There were negative correlations between LS BMD and FN BMD values and age, menopause duration, total breastfeeding duration, and number of breastfeeding per day. There were positive correlations between LS and FN BMD values, and weight and BMI scores. Additionally, there were negative correlations between LS and FN BMD values, and age of menarche and number of deliveries. In linear stage regression analysis, weight, number of breastfeeding per day, postmenopausal duration, duration of total breastfeeding and age of menarche were defined as the most significant predictors for LS BMD, whereas weight, postmenopausal duration and number of breastfeeding per day were defined as the most significant predictors for FN BMD. Conclusion: LS and FN BMD in postmenopausal women are related to reproductive factors, so reproductive factors should also be considered in the evaluation of risk factors in postmenopausal women.

The Journal of nutrition, 2000

The objective of this work was to compare long-term changes in bone mineral in lactating (L) and nonlactating (NL) women for 2 y postpartum. The 40 L women (mean duration of breastfeeding 345 +/- 177 d) and 36 NL women were enrolled during late pregnancy. Subjects were healthy and nonsmoking with a mean age of 28.8 +/- 4.1 y. Bone mineral content (BMC) was measured at 0.5, 3, 6, 12, 18 and 24 mo by dual-energy X-ray absorptiometry set for total body scan with regional analysis. BMC adjusted for bone area, weight and height (adj-BMC) decreased in L women at the lumbar spine (-3.1%, P &lt; 0. 001) and pelvis (-0.9%, P = 0.03) by 3 mo, and at the total body (-0. 9%, P = 0.05) by 6 mo. Losses were recovered following onset of menses. Adj-BMC at the lumbar spine, pelvis, thoracic spine and total body increased over baseline by 24 mo in L women. In NL women, adj-BMC increased over baseline within 3 mo and continued to increase thereafter. Net total-body gains were greater in the 27 NL wom...

2000

The objective of this work was to compare long-term changes in bone mineral in lactating (L) and nonlactating (NL) women for 2 y postpartum. The 40 L women (mean duration of breastfeeding 345 Ϯ 177 d) and 36 NL women were enrolled during late pregnancy. Subjects were healthy and nonsmoking with a mean age of 28.8 Ϯ 4.1 y. Bone mineral content (BMC) was measured at 0.5, 3, 6, 12, 18 and 24 mo by dual-energy X-ray absorptiometry set for total body scan with regional analysis. BMC adjusted for bone area, weight and height (adj-BMC) decreased in L women at the lumbar spine (Ϫ3.1%, P Ͻ 0.001) and pelvis (Ϫ0.9%, P ϭ 0.03) by 3 mo, and at the total body (Ϫ0.9%, P ϭ 0.05) by 6 mo. Losses were recovered following onset of menses. Adj-BMC at the lumbar spine, pelvis, thoracic spine and total body increased over baseline by 24 mo in L women. In NL women, adj-BMC increased over baseline within 3 mo and continued to increase thereafter. Net total-body gains were greater in the 27 NL women who completed the final measurement than in their 26 L counterparts (ϩ2.3% vs. ϩ0.6%, P ϭ 0.001). Net regional gains differed at the head, legs, and ribs, but not at the lumber spine, pelvis or thoracic spine. Duration of breastfeeding, parity, onset of menses and maternal age affected bone changes in L women. These results indicate that lactation delays bone mineral accretion and temporarily alters its regional distribution in postpartum women. J. Nutr. 130: 777-783, 2000.

Bjog-an International Journal of Obstetrics and Gynaecology, 1992

Objective To determine if women who suffer from early pregnancy loss are at increased risk of osteoporosis later in life.Design Part of a Community screening project for bone mineral density (BMD).Subjects 392 women aged 50–54 who had had from 0 to 6 miscarriages out of 0 to 8 term pregnancies.Technique BMD measured using dual energy X-ray absorptiometry at both the lumbar spine and the proximal femur.Results The mean BMD in nulligravid women was not significantly different from those whose only pregnancies ended in early loss. There was no significant correlation between the BMD at either the lumbar spine or the proximal femur and the number of miscarriages (r= 0.03 and 0.01, respectively). The BMD of the lumbar spine and femoral neck were not affected by parity (P= 0.08 and P= 0.87, respectively).Conclusion The risk of osteoporosis was not influenced by parity or the number of previous miscarriages.

Archives of Gynecology and Obstetrics, 2012

Background There are conflicting opinions in the literature about whether pregnancy influences maternal bone density or osteoporosis development. The study aim was to investigate whether there is a significant alteration in maternal bone density during normal pregnancy. Methods Bone mass of 200 pregnant women aged 22-42 years was measured twice with quantitative ultrasonometry (QUS) of the heel (Os calcaneum). The first measurement was performed between the 10th and 22nd week of pregnancy, follow-up of 149 women took place 0-9 days postpartum. A questionnaire focusing on data affecting bone metabolism and bone turnover was handed out at the first visit. Results Median reduction in speed of sound (SOS) was 11 m/s at follow-up indicating a decline of the stiffness during pregnancy. No significant correlation was found between lactation period and the obtained values for stiffness, SOS, T score and Z score. For broadband ultrasonographic attenuation, there was a statistically significant difference (p \ 0.05) between women who had and had not breastfed. Parameters from patients with a family history of osteoporosis (n = 30) compared to patients without did not reveal statistical significance during pregnancy. Glucocorticoid therapy, nicotine consumption, physical exercise and nutrition was not statistically significant (p [ 0.05). SOS value of women with a twin pregnancy was different over the study period (p \ 0.05). Conclusion A reduction in bone mass is possible during pregnancy. Routine evaluation of the bone density in all pregnant women does not seem to be justified; however, it is reasonable in women who present with risk factors. These women could be screened with QUS.

Aging Clinical and Experimental Research, 2015

Aim The aim of this study was to investigate the possible risk factors related with osteoporosis in women with spontaneous menopause. Methods Five hundred and one postmenopausal women were divided into three groups as normal, osteopenic and osteoporotic according to their bone mineral density (BMD). By face-to-face interview, parity, age at menarche, age at menopause, duration of fertility, duration of menopause, first pregnancy age, total lactation period, exercise, smoking were assessed. Women with menopause age before 40 years, surgical menopause, who had any anti-osteoporosis treatment, hormone replacement therapy at the time of BMD measurement and corticosteroid use longer than 6 months were excluded from the study. Results Among 501 postmenopausal women, 107 women were classified as normal, 170 as osteopenic and 224 as osteoporotic. Among demographic features of patients, there was statistically significant difference between the groups in age, BMI and parity (p \ 0.001, p \ 0.0001 and p = 0.002, respectively). There were statistically significant differences between the groups in case of age at menopause, duration of fertility and duration of menopause (p = 0.013, p = 0.013 and p \ 0.0001, respectively). In the multivariate logistic regression analysis, BMI over 32 and fertility duration over 33 years had a statistically significant protective effect against osteoporosis (OR 0.42, CI 95 % 0.27-0.66; OR 0.36, CI 95 % 0.24-0.56, respectively), but age was positively correlated with osteoporosis (OR 1.13, CI 95 % 1.01-1.17) Conclusions Duration of fertility (years of menstruation) longer than 33 years and body mass index higher than 32 seem to protect against postmenopausal osteoporosis. Age is also an independent risk factor for postmenopausal osteoporosis. Keywords Postmenopausal osteoporosis Á Risk factors Á Lactation Á First pregnancy age Á Duration of fertility Á Body mass index This study has been accepted as poster presentation in 23th EBCOG European Congress of Obstetrics and Gynaecology in Glasgow, Scotland (UK), on May 7th-10th 2014.

Public Health Nutrition, 2009

ObjectiveBone mineral density (BMD) loss has been described in adult women in the 12-month postpartum period. However, little is known about the precise BMD pattern in adolescent mothers. The present study aimed to evaluate BMD in Argentinean adolescent mothers followed up during the 12-month postpartum period.DesignAnalytical, prospective clinical trial. BMD and body composition were determined by dual-energy X-ray absorptiometry; bone mineral content (BMC) and BMD were measured in the lumbar spine (L2–L4), femoral neck (FN), femur trochanter (TR), total hip (TH) and total body. Changes in BMD and BMC were analysed using ANOVA for pairwise comparisons. Other comparisons were performed with the paired-sample t test and Wilcoxon test; Pearson’s correlation coefficient was used to analyse the relationship among continuous variables.SettingLa Plata, Argentina.SubjectsAdolescent mothers (n 35; 17 years old or less) were recruited within 15 d after delivery. Studies and follow-up were pe...

Calcified Tissue International

During lactation, changes in maternal calcium metabolism are necessary to provide adequate calcium for newborn skeletal development. The calcium in milk is derived from the maternal skeleton through a process thought to be mediated by the actions of parathyroid hormone-related protein (PTHrP) in combination with decreased circulating estrogen concentrations. After weaning, bone lost during lactation is rapidly regained. Most studies of bone metabolism in lactating women have been performed in Caucasian subjects. There are well-documented differences between African American (AA) and Caucasian (C) bone metabolism, including higher bone mineral density (BMD), lower risk of fracture, lower 25-hydroxyvitamin D (25(OH) D), and higher PTH in AA compared to C. In this prospective paired cohort study, BMD and markers of bone turnover were compared in self-identified AA and C mothers during lactation and after weaning. BMD decreased in both AA and C women during lactation, with similar decre...

Gynecological Endocrinology, 2005

To evaluate the impact of pregnancy on bone, we studied bone turnover at the first (T1) and third (T3) trimester of gestation in 58 adolescents and 28 healthy adolescents who had never been pregnant. Total body (TB) and lumbar spine (LS) bone mineral density (BMD) and body composition were evaluated by dual-energy X-ray absorptiometry in all control patients (C) and after parturition in 28 pregnant patients (G). Paired and unpaired t tests, Mann-Whitney and Pearson correlation tests were used. Bone turnover markers were above the reference range for adult women in more than 80% of the adolescents, with no difference between C and G patients at T1. Increase in urinary N-telopeptide crosslinks of type I collagen and serum bonespecific alkaline phosphatase, markers of bone turnover, was seen during pregnancy (p 5 0.0001). Body composition did not differ between groups, but LS BMD, percentage of expected LS BMD, LS Z-score, percentage of expected TB BMD and TB Z-score were lower in G than C patients (p 5 0.05). TB BMD was positively correlated with LS BMD (r 2 ¼ 0.52). The inverse correlations between bone markers and LS BMD suggest that the increased bone turnover during pregnancy probably explains the low bone density after parturition. The impact on future peak bone mass must be studied.