A case series of pregnancy- and lactation-associated osteoporosis and a review of the literature

Bone Metabolism, Bone Mass, and Bone Structure During Pregnancy and Lactation: Normal Physiology and Pregnancy and Lactation-Associated Osteoporosis

This article reviews bone metabolism, bone mass, and bone structure changes expected during and after pregnancy and lactation, as well as the condition of pregnancy and lactation-associated osteoporosis (PLO)-a presentation with fragility fracture(s) in the context of these physiologic changes. Clinical implications of physiologic bone changes will be addressed, as will specific management considerations that apply to premenopausal women with PLO.

Minodronate for severe multiple vertebral fractures due to pregnancy- and lactation-associated osteoporosis: a case report and literature review

Pregnancy- and lactation-associated osteoporosis (PLO) is a rare type of premenopausal osteoporosis, typically occurring during the third trimester of pregnancy and the early postpartum lactation period. This report presents a case involving severe multiple vertebral fractures due to PLO with low bone mineral density (BMD) and heightened bone turnover. A 39-year-old primiparous Japanese woman reported low back pain (LBP) starting at 28 weeks of pregnancy. The pain temporarily improved after delivery, although the LBP recurred and worsened 2 months into breastfeeding. Thereafter, the patient visited the Obstetrics and Orthopedic departments. Plain radiographs of the thoracic and lumbar spine showed loss of vertebral body height at the T4-12 and L1-3,5 vertebrae, leading to a diagnosis of 13 fractured vertebrae. BMD and serum bone turnover markers revealed low bone density and heightened bone turnover. In the absence of any identified alternative cause of secondary osteoporosis, the diagnosis was severe PLO with 13 vertebral fractures related to pregnancy and lactation. After treatment with bisphosphonates and an active vitamin D analog, the patient exhibited an increased BMD and normalization of bone turnover and resumed regular daily activities. Although the optimal PLO treatment strategy remains uncertain, bisphosphonates are an option; however, bisphosphonates can potentially affect the fetus through placental transfer. Therefore, careful consideration is required for patients planning pregnancy. Despite bisphosphonates' widespread use and cost-effectiveness, selecting PLO medications involves multiple factors, necessitating further research.

Low serum lipase levels in mothers of children with stunted growth indicate the possibility of low calcium absorption during pregnancy: A cross-sectional study in North Sumatra, Indonesia

Stunting is caused by various factors, including low nutritional intake in the first two years of life. This study aimed to investigate the differences in sociodemographic factors and mineral, vitamin, and enzyme parameters in mothers associated with the occurrence of stunting in children. We conducted a cross-sectional study from September to November 2020 on North Sumatra Island, Indonesia. The data collected included sociodemographic characteristics, pregnancy history, birth history, food intake, and laboratory examinations, including measurements of calcium, iron, zinc, vitamin D, pancreatic amylase, and serum lipase levels. This study included 50 healthy mothers aged 18-50 years old with children aged 2 to 60 months. There was a significant difference in serum calcium levels between the groups of mothers of children with normal and stunted growth (p = 0.03, mean difference±standard error (SE) = 0.23±0.12, 95% CI: 0.19-0.45). All of the study subjects were categorized as vitamin D deficient. The mean lipase level in the group of mothers of children with stunted growth was significantly lower than that in the group of mothers of children with normal growth (p = 0.02, mean difference±SE = 4.34±1.83, 95% CI: 0.62-8.06). The conclusion was that serum lipase levels were significantly lower in mothers of children with stunted growth compared to mothers of children with normal growth. Serum lipase levels this low are likely to indicate that a mother is unable to meet her child's calcium needs during pregnancy, increasing the child's risk of stunted growth.

Comparative Effectiveness of Therapeutic Interventions in Pregnancy and Lactation-Associated Osteoporosis: A Systematic Review and Meta-analysis

CONTEXT

The optimal management of pregnancy and lactation-associated osteoporosis (PLO) has not been designated.

OBJECTIVE

To systematically review the best available evidence regarding the effect of different therapeutic interventions on bone mineral density (BMD) and risk of fractures in these patients.

METHODS

A comprehensive search was conducted in PubMed/Scopus databases until December 20, 2022. Data were expressed as weighted mean difference (WMD) with 95% CI. The I2 index was employed for heterogeneity. Studies conducted in women with PLO who received any antiosteoporosis therapy were included. Studies including women with secondary causes of osteoporosis or with transient osteoporosis of the hip were excluded. Data extraction was independently completed by 2 researchers.

RESULTS

Sixty-six studies were included in the qualitative analysis (n = 451 [follow-up time range 6-264 months; age range 19-42 years]). The increase in lumbar spine (LS) BMD with calcium/vitamin D (CaD), bisphosphonates, and teriparatide was 2.0% to 7.5%, 5.0% to 41.5%, and 8.0% to 24.4% at 12 months, and 11.0% to 12.2%, 10.2% to 171.9%, and 24.1% to 32.9% at 24 months, respectively. Femoral neck (FN) BMD increased by 6.1% with CaD, and by 0.7% to 18% and 8.4% to 18.6% with bisphosphonates and teriparatide (18-24 months), respectively. Meta-analysis was performed for 2 interventional studies only. Teriparatide induced a greater increase in LS and FN BMD than CaD (WMD 11.5%, 95% CI 4.9-18.0%, I2 50.9%, and 5.4%, 95% CI 1.2-9.6%, I2 8.1%, respectively).

CONCLUSION

Due to high heterogeneity and lack of robust comparative data, no safe conclusions can be made regarding the optimal therapeutic intervention in women with PLO.

Fractures within 2 years of an obstetric hospitalization: analysis of nationwide administrative data in Japan

INTRODUCTION

Pregnancy- and lactation-associated osteoporosis (PLO) is a condition in which young women develop fractures during pregnancy or breastfeeding. Though PLO is a severely debilitating disease, its pathophysiology and epidemiology have not been clarified and its treatment has not been established. We aimed to identify the incidence and factors associated with fractures occurring within 2 years following an obstetric hospitalization.

MATERIALS AND METHODS

We extracted data on fractures occurring within 2 years of an obstetric hospitalization from the Japanese Diagnosis Procedure Combination database. We analyzed the implementation of bone mineral density and bone metabolism marker tests, prescription status, and factors associated with fractures occurring within 2 years of an obstetric hospitalization.

RESULTS

Among 837,347 patients with a history of obstetric hospitalization from 2010 to 2014, 379 patients had a history of hospitalization due to a fracture occurring within 2 years (4.5/10,000 pregnancies). Among the patients with fractures occurring within 2 years of an obstetric hospitalization, 6.7% underwent bone mineral quantification or a bone metabolism marker test, and 7.5% were prescribed a lactation inhibitor or osteoporosis treatment. Factors associated with fractures occurring within 2 years following an obstetric hospitalization identified included Cushing syndrome, Charlson Comorbidity Index score ≥ 1, age ≥ 40 years old at pregnancy, smoking history, and steroid administration.

CONCLUSION

We investigated fracture cases occurring within 2 years of an obstetrics hospitalization. This finding may be useful in selecting preventative measures for patients at risk of fractures within 2 years after obstetric hospitalization, including PLO.

Bone metabolism in pregnancy and lactation

INTRODUCTION

Different hormonal mechanisms regulate bone metabolism during pregnancy and lactation. In both those periods of life, a fine modulation of calcium metabolism is necessary to meet the needs of foetus and newborn.

METHODS

We review scientific literature on the topic "osteoporosis", "pregnancy" and "lactation", evaluating the most relevant data from original articles, reviews and meta-analyses.

EVIDENCE SYNTHESIS

Pregnancy- and lactation-associated bone loss and related fractures rarely occur and, generally, clinicians have to manage it case to case, since there is not a unique guideline. Fortunately, bone mineral density (BMD) usually tends to recover within 12 months after weaning, thus, it could be reasonable waiting of assessing the effective magnitude of bone mass regain before starting any pharmacological treatment.

CONCLUSIONS

Osteoporosis and/or fragility fractures remain uncommon events associated with gestation and/or breastfeeding. The management of bone loss and/or fractures during those periods is generally conservative and a tailored approach is advisable in the absence of any specific recommendation in this field.

Pregnancy- and lactation-associated vertebral compression fractures: MRI prevalence and characteristics

The frequency of pregnancy- and lactation-associated vertebral compression fractures (PLVCFs) is not known. This study showed that MRI prevalence of PLVCFs was approximately 0.5% in females ≥ 15 and < 40 years of age over a 48-month period. PLVCFs did not display MRI features distinguishing them from other vertebral insufficiency fractures.

PURPOSE

We aimed to investigate the MRI prevalence and characteristics of pregnancy- and lactation-associated vertebral compression fractures (PLVCFs).

METHODS

This retrospective cross-sectional observational study included all thoracic, lumbar, or thoracolumbar MRI examinations performed in our hospital (or at outside centers and referred to us for consultation) of females ≥ 15 and < 40 years of age during a 48-month period. Two radiologists independently reviewed all images for vertebral compression fractures and their disagreement was resolved by a third blinded senior radiologist with 24 years of dedicated musculoskeletal radiology experience. MRI features of PLVCFs (early/late stage, height loss, endplate involvement, retropulsion) were noted.

RESULTS

A total of 1484 MRI examinations-including 50 consultations from outside centers-of 1260 females (mean age, 27.7 years; range, 15-39) were included. Interobserver agreement of the two junior radiologists was substantial (κ = 0.607; 95% CI, 0.545-0.669). Vertebral compression fractures were identified in 177 of thoracic (n = 210), lumbar (n = 900), or thoracolumbar MRI (n = 374) examinations. Six women (7 MRI examinations; 4.0% of MRIs with vertebral fractures) had PLVCFs diagnosed on MRI (prevalence, 0.47%; mean age, 31 years; age range, 25-37). Number of fractured vertebrae in cases with PLVCF ranged between 1 and 11 (mean, 5.6). DEXA, available in all patients with PLVCFs, verified osteopenia/osteoporosis in four of six patients.

CONCLUSION

PLVCFs have an MRI prevalence of approximately 0.5% in the target population and do not display distinguishing features from other insufficiency type vertebral compression fractures.

A case of pregnancy and lactation-associated osteoporosis and a review of the literature

INTRODUCTION

The pregnancy and lactation-associated osteoporosis (PLO) is a rare disease whose precise pathophysiological mechanisms remain mostly unknown.

CASE REPORT

We reported here a case of PLO that occurred in the early postpartum period and led to multiple compression fractures. Combination therapy with alendronate, calcium carbonate, and vitamin D was used to treat the patient and a marked but gradual increase in the density of bone mineral was observed. Moreover, no further fractures have occurred.

CONCLUSION

PLO is a very rare type of osteoporosis associated with severe chronic back pain. Increased bone resorption significantly increases the risk of bone fractures in women with PLO. Early diagnosis, stopping breastfeeding, treatment of calcium and vitamin D, bisphosphonates, or other antiosteoporosis medicine and regular follow-ups of these cases are particularly important in the prevention of fractures and to increase the quality of life of patients.

Unexpected rapid increase in bone mineral density by bisphosphonate therapy after multiple spinal fractures: a case report

Background

Osteoporosis is a serious disease that causes bone fragility fractures and increases mortality. Bisphosphonates are the first-line drugs for osteoporosis. However, the gains in bone mineral density by use of bisphosphonates alone are limited.

Case presentation

We describe the clinical outcome of a Japanese woman with osteoporosis treated with bisphosphonates after multiple spinal fractures. After 3 years of treatment with the bisphosphonate alendronate, her lumbar bone mineral density and bilateral hip bone mineral density markedly increased by 61.9% and 32.5%, respectively.

Conclusion

We considered that our patient’s multiple fractures had caused a decrease in bone mineral density, which naturally improved with fracture healing to enhance the increase in bone mineral density with bisphosphonate treatment.

Women With Pregnancy and Lactation-Associated Osteoporosis (PLO) Have Low Bone Remodeling Rates at the Tissue Level

Pregnancy and lactation-associated osteoporosis (PLO) is a rare, severe, early form of osteoporosis in which young women present with fractures, usually multiple vertebral fractures, during late pregnancy or lactation. In studies of idiopathic osteoporosis (IOP) in premenopausal women, we enrolled 78 women with low-trauma fractures and 40 healthy controls, all with normal menses and no secondary cause of bone loss. In 15 of the affected women, the PLO subgroup, fractures had occurred during late pregnancy or lactation. We hypothesized that clinical, bone structural, and metabolic characteristics would differ between women with PLO and those with (non-PLO) IOP and controls. All were evaluated > 12 months postpartum, when structural and remodeling characteristics would be expected to reflect baseline premenopausal status rather than transient postpartum changes. As previously reported, affected subjects (PLO and IOP) had BMD and microarchitectural deficiencies compared to controls. Women with PLO did not differ from those with IOP in terms of age, BMI, body fat, menarcheal age, parity, or age at first pregnancy. However, women with PLO had a more severe clinical presentation than those with IOP: more fractures (5.5 ± 3.3 versus 2.6 ± 2.1; p = 0.005); more vertebral fractures (80% versus 17%; p < 0.001); and higher prevalence of multiple fractures. BMD deficits were more profound and cortical width tended to be lower in PLO. PLO subjects also had significantly lower tissue-level mineral apposition rate and bone formation rates (0.005 ± 0.005 versus 0.011 ± 0.010 mm² /mm/year; p = 0.006), as well as lower serum P1NP (33 ± 12 versus 44 ± 18 µg/L; p = 0.02) and CTX (257 ± 102 versus 355 ± 193 pg/mL; p = 0.01) than IOP. The finding that women with PLO have a low bone remodeling state assessed more than a year postpartum increases our understanding of the pathogenic mechanism of PLO. We conclude that women with PLO may have underlying osteoblast functional deficits which could affect their therapeutic response to osteoanabolic medications. © 2019 American Society for Bone and Mineral Research.

Changes in bone metabolic profile associated with pregnancy or lactation

Calcium and nutrients are transferred from mothers to fetuses or infants during pregnancy or lactation, respectively, promoting metabolic changes in the mother, many uncharacterized. To evaluate these changes, we undertook two parallel studies. In one we analyzed fourteen clinical cases of vertebral fragility fractures, at or before three months after partum, in mothers who breastfed their infants. In the other, we enrolled 79 additional pregnant subjects, some who chose to breastfeed and others who did not, and analyzed changes in bone metabolic status starting between 34 and 36 weeks of gestation and ending one month after partum. In the larger group, bone-resorbing and bone-forming parameters such as serum TRACP5b and osteocalcin, respectively, significantly increased after partum. Among parameters that changed after partum, serum PTH and the bone-resorbing markers serum TRACP5b and urine NTX were significantly higher in mothers who only breastfed infants compared to mothers who fed infants formula or a mix of both. However, bone-forming parameters were comparable between breastfeeding and non-breast-feeding groups after partum, suggesting that elevated bone-resorption occurs only in the breastfeeding group. Radiographic analysis after partum demonstrated that no subject among the 79 analyzed showed vertebral fractures, even those who breastfed exclusively. Among fracture cases analyzed, subjects exhibited significantly lower bone mineral density than did non-fracture cases in breastfeeding-only subjects. We conclude that bone metabolic status significantly changes over the period between pregnancy and post-partum lactation, and that low bone mineral density seen in a small subset of breastfeeding-only cases likely causes post-partum vertebral fragility fractures.

The relationship between maternal and child bone density in Nigerian children with and without nutritional rickets

We found a positive relationship between bone density in Nigerian children with and without rickets and that of their mothers. After treatment, children with rickets had greater bone density than children without rickets, indicating that children genetically programmed to have greater bone density may have a higher risk of rickets.

INTRODUCTION

To determine the relationship between bone density in children with and without rickets and that of their mothers METHODS: Using an unmatched case-control design, forearm areal bone mineral density (aBMD) was measured in 52 and 135 Nigerian children with and without rickets and their mothers, respectively. We performed multivariate linear regression analyses to assess the relationship between maternal and child aBMD Z-scores.

RESULTS

Forearm aBMD Z-scores in children were associated with maternal aBMD Z-scores at metaphyseal (effect estimate 0.23; 95% CI 0.08 to 0.37) and diaphyseal (effect estimate 0.16; 0.01 to 0.30) sites, after adjustment for rickets in the child, child's age and sex, height-for-age Z-score, and weight-for-age Z-score. In the adjusted model, rickets was inversely associated with child's aBMD Z-score at the diaphyseal site only (- 0.45, - 0.65 to - 0.24). The positive relationship between maternal and child aBMD Z-scores was marginally greater in children with rickets (slope 0.56, r = 0.47) than without rickets (slope 0.19, r = 0.20) at the diaphyseal site only (P = 0.06 for interaction) but not at the metaphyseal site (slopes 0.35 and 0.30, respectively, P = 0.48). After treatment with calcium for 6 months, metaphyseal aBMD Z-scores were greater in children with treated rickets (effect estimate 0.26; 95% CI 0.02 to 0.49) than in those without rickets.

CONCLUSION

In Nigerian children with and without rickets, forearm aBMD Z-scores were positively associated with maternal aBMD Z-scores. Active rickets in the child marginally modified the relationship at the diaphyseal site only. After treatment, children with rickets had greater metaphyseal aBMD Z-scores than children without rickets.

Adequate nutrition status important for bone mineral density improvement in a patient with anorexia nervosa

Low bone mineral density (BMD) is one of the most frequent complications of anorexia nervosa (AN). We report the clinical outcomes of a female patient with severe AN, whose chest had become deformed due to thoracic fracture. Lumbar BMD was 0.358 g/cm² (T-score = −6.3), and total hip BMD was 0.411 g/cm² (T-score = −4.4). Active vitamin D increased these parameters by 81.0% and 57.4%, respectively, but a drop in her nutrition status afterward resulted in a sharp decrease in BMD values. These findings suggest that adequate nutrient intake is essential for effective osteoporosis treatment in patients with AN.

Subsequent fracture risk of women with pregnancy and lactation-associated osteoporosis after a median of 6 years of follow-up

Almost a quarter of patients with PAO will sustain a subsequent fracture; patients need to be informed about potential risks before deciding for further pregnancies.

INTRODUCTION

Pregnancy and lactation-associated osteoporosis (PAO) is a severe type of premenopausal osteoporosis which predominantly occurs in the last trimester of pregnancy or immediately postpartum. Long-term follow-up data including subsequent fracture risk have yet to be reported.

METHODS

This single-center prospective cohort study investigated the subsequent fracture risk of all 107 patients with PAO who were referred to our institution.

RESULTS

Overall, 107 presented with at least one fracture. Each patient sustained on average four fractures most commonly at the thoracolumbar spine. During a median of 6 years of follow-up, 26 (24.3%) of patients who had a fracture at baseline reported a subsequent fracture. Overall, 30 PAO patients (28%) reported a further pregnancy. In subsequent pregnancies, 6 (20%) of patients reported a subsequent fracture. Patients with up to 1 vs. > 1 fracture at time of diagnosis showed a 3 (10%) and 25 (27%) subsequent fracture rate, respectively (p = 0.047). There was a significant correlation between the number of fractures at time of diagnosis and subsequent fracture risk (N = 26,p= 0.56, p = 0.003).

CONCLUSIONS

Almost a quarter of patients with PAO will sustain a subsequent fracture, and this fracture risk correlates with the number of fractures at time of diagnosis. Patients with PAO need to be informed about their potential subsequent fracture risk before deciding for further pregnancies.

Approach to the patient with pregnancy and lactation-associated osteoporosis: A case report and a review of the literature

RATIONALE

Pregnancy and lactation-associated osteoporosis (PLO) is very rare, but it can cause severe vertebral compression fractures with disabling back pain. Although it is a rare, PLO must be kept in mind in the differential diagnosis in patients presenting with low back pain during or after pregnancy.

PATIENT CONCERNS

A 23-year-old woman who suffered from lumbago and fractures in the vertebral column 1 month after delivery.

DIAGNOSIS

Pregnancy and lactation-associated osteoporosis.

INTERVENTIONS

Combination therapy of calcium and vitamin D were used for treatment, as well as regular follow-up.

OUTCOMES

The patient's back pain had decreased significantly, the bone metabolic index, bone mineral density (BMD) had improved and she did not experience any recurrence.

LESSONS

Early diagnosis and treatment of calcium and vitamin D, as well as the efficacy of PLO intervention monitoring and evaluation are critical for the success of treatment.

Pregnancy-associated osteoporosis: a case-control study

The etiology and underlying mechanisms of pregnancy-associated osteoporosis (PAO) are still unknown, since no systematic analyses exist. Our results indicate that PAO is a heterogeneous, rare but severe disease including a substantial number of fractures with a significant delay from first symptom to diagnose.

INTRODUCTION

Pregnancy-associated osteoporosis (PAO) is a rare but severe type of premenopausal osteoporosis. Most common symptom includes acute lower back pain due to vertebral fracture predominantly occurring in the last trimester of pregnancy or immediately postpartum. The exact underlining mechanisms and risk factors of PAO are still unknown, and up to date, there are no published systematic analyses.

METHODS

We identified 102 PAO patients and matched them with 102 healthy controls according to age, region, and gravidity to evaluate risk factors in a large and homogenous population of women.

RESULTS

The baseline characteristics and anthropometric data of the two study groups were similar. Eighty-eight percent of the patients with PAO suffered from one or more fractures with a mean of 3.3 fractures per patient. The most common fracture site was the thoracolumbar spine, whereas 29, 37, 48, and 35% of the patients reported fractures at TH11, TH12, L1, and L2, respectively. PAO patients suffered more frequently from excessive dental problems in childhood (p < 0.001). The control group performed significantly more frequently sports both before (p < 0.002) and after puberty (p < 0.01). Compared to the controls, the patients with PAO reported twice as often severe diseases during pregnancy (p < 0.029). Hereby, the frequency of immobilization was twice as often in the PAO group compared to that in the control group (p < 0.005).

CONCLUSIONS

Our results indicate that PAO is a heterogeneous, rare but severe disease including a substantial number of fractures with a significant delay from first symptom to diagnose. Increased awareness is warranted to immediately start effective treatment.

Two cases of pregnancy- and lactation- associated osteoporosis successfully treated with denosumab

Case 1. A 35-year-old woman in the 8^th month of her first pregnancy suffered acute lumbar pain that persisted for 4 months. In the 5^th month postpartum an acute increase in the low back pain led to a MRI which showed recent deformity in L1 and deformities of undetermined time of evolution in L2, L4, and L5. Laboratory evaluation did not reveal metabolic derangements. She had low bone mineral density (BMD, DXA) and severe deterioration of the microarchitecture of distal appendicular bone (HR-pQCT). Kyphoplasty of all 4 vertebrae was performed in 2 stages, and treatment with subcutaneous denosumab, 60 mg every 6 months, was begun. There was rapid and almost complete improvement in pain. An increase in trabecular bone was documented with HR-pQCT. Case 2. A 33-year-old mother who was breastfeeding her first-born child experimented acute dorsal pain. RMI revealed partial compression fractures in vertebrae D5-7. Her axial BMD was low. There was no family history of osteoporosis, and causes of secondary osteoporosis were ruled out. Her pain slowly subsided with conservative measures, oral analgesics, and nasal calcitonin. Then, treatment with oral strontium ranelate was prescribed; after 3 months serum alkaline phosphatase and osteocalcin had not increased, and after one year lumbar bone mineral density (BMD) was unchanged. Treatment was switched to subcutaneous denosumab. After one year, lumbar BMD had increased 14%, and the pain had almost completely subsided.