Ultrasound measurement of pregnancy-induced changes in maternal bone mass: a longitudinal, cross-sectional and biochemical study

Management of pathological femoral fracture secondary to breast cancer in pregnancy: A case report

Bone metastasis resulting from breast cancer in pregnancy is rare. In the literature there are few reports regarding osteolytic lesions in pregnancy and no data on the treatment of such femoral fractures. The present study reports a case of a 29-week primigravida presenting with severe lumbosciatica in the left side, refractory to medical therapy. During neurosurgical examination a spontaneous pathological fracture of the left femur occurred. Damage control orthopedic principals were applied and a biopsy specimen from the femoral lesion was obtained, providing a diagnosis of metastases from breast adenocarcinoma. Cesarean section was performed at 32 gestational weeks. Following delivery, an internal fixator was placed in the left femur for definitive treatment of the fracture and staging of cancer was conducted. Subsequently, adjuvant treatment comprising left mastectomy and percutaneous radiofrequency thermoablation of the sacroiliac lesion were performed. A follow-up one-year following percutaneous radiofrequency thermoablation of the sacroiliac lesion detected no metastatic bone pain, and identified a stable sacroiliac lesion.

Calcium economy in human pregnancy and lactation

Pregnancy and lactation are times of additional demand for Ca. Ca is transferred across the placenta for fetal skeletal mineralisation, and supplied to the mammary gland for secretion into breast milk. In theory, these additional maternal requirements could be met through mobilisation of Ca from the skeleton, increased intestinal Ca absorption efficiency, enhanced renal Ca retention or greater dietary Ca intake. The extent to which any or all of these apply, the underpinning biological mechanisms and the possible consequences for maternal and infant bone health in the short and long term are the focus of the present review. The complexities in the methodological aspects of interpreting the literature in this area are highlighted and the inter-individual variation in the response to pregnancy and lactation is reviewed. In summary, human pregnancy and lactation are associated with changes in Ca and bone metabolism that support the transfer of Ca between mother and child. The changes generally appear to be independent of maternal Ca supply in populations where Ca intakes are close to current recommendations. Evidence suggests that the processes are physiological in humans and that they provide sufficient Ca for fetal growth and breast-milk production, without relying on an increase in dietary Ca intake or compromising long-term maternal bone health. Further research is needed to determine the limitations of the maternal response to the Ca demands of pregnancy and lactation, especially among mothers with marginal and low dietary Ca intake, and to define vitamin D adequacy for reproductive women.

Bone mineral density changes during pregnancy in actively exercising women as measured by quantitative ultrasound

Objective

To evaluate whether bone mineral density (BMD) changes in women engaged in active exercises during pregnancy would be different from non-exercising women.

Methods

Consecutive patients with singleton pregnancies who were engaged in active exercise training during pregnancy were prospectively recruited over a period of 6 months. Quantitative USG measurements of the os calcis BMD were performed at 14–20 weeks and at 36–38 weeks. These patients were compared to a control cohort of non-exercising low-risk women.

Results

A total of 24 physically active women undergoing active physical training of over 10 h per week at 20 weeks gestation and beyond (mean 13.1 h, SD 3.3) were compared to 94 non-exercising low-risk women. A marginal fall in BMD of 0.015 g/cm² (SD 0.034) was demonstrable from early to late gestation in the exercising women, which was significantly lower than that of non-exercising women (0.041 g/cm²; SD 0.042; p = 0.005). Logistic regression models confirmed that active exercises in pregnancy were significantly associated with the absence of or less BMD loss in pregnancy.

Conclusion

In women actively engaged in physical training during pregnancy, the physiological fall in BMD during pregnancy was apparently less compared to those who did not regularly exercise.

Bone mineral density changes in pregnancies with gestational hypertension: a longitudinal study using quantitative ultrasound measurements

OBJECTIVE

To compare the maternal bone mineral density (BMD) changes in gestational hypertensive and normotensive pregnancies using quantitative ultrasound.

METHODS

Consecutive patients were recruited from a general obstetric clinic over a period of 9 months. BMD measurements were performed at the os calcis in early pregnancy before 20 weeks and in the late third trimester after 36 weeks, using a Hologic Sahara Clinical Bone Sonometer system. These patients were followed up in accordance with standard antenatal protocol. The diagnosis of gestational hypertension (GH) was made based on a standard institutional protocol. The changes in BMD from early to late pregnancy were compared between those with/without GH.

RESULTS

A total of 450 patients with complete data were analyzed. The overall incidence of GH was 4.8% (n = 22), of which 1.7% (n = 8) fulfilled the definitions of severe pre-eclampsia. A mean BMD loss of 0.0382 g/cm2 (around 6% of early pregnancy BMD) [corrected] was demonstrable from early to late gestation The hypertensive group has marginally higher mean BMD loss as compared to the normotensive group (0.052 vs. 0.037 g/cm²; P = 0.037). However, regression analysis models showed that early pregnancy BMD values, early pregnancy fat percentage and fat accumulation in pregnancy were significant factors affecting BMD loss during pregnancy, while GH was not in the equations.

CONCLUSION

The development of gestational hypertensive disorders apparently does not have any significant impact on BMD changes during pregnancy.

Bone mineral density changes in gestational diabetic pregnancies-a longitudinal study using quantitative ultrasound measurements of the os calcis

To compare the maternal bone mineral density (BMD) changes in gestational diabetic and non-diabetic pregnancies using quantitative ultrasound measurements of the os calcis, BMD measurements were performed at the os calcis in early pregnancy before 20 weeks and in the late third trimester after 36 weeks, using a Hologic Sahara Clinical Bone Sonometer system. Random glucose screening and direct oral glucose tolerance testing were used to diagnose gestational diabetes mellitus (GDM) according to World Health Organization criteria, which was then treated according to a standard protocol. In a cohort of 480 patients, there were 96 gestational diabetic patients (14 GDM and 82 with impaired glucose tolerance). The mean BMD loss was higher in diabetic patients compared with controls (0.038 vs. 0.025 g/cm2, p = 0.048). A regression model of all pregnancies showed that higher fat accumulation was related to lower BMD loss, but diabetic status was not in the equation. Within diabetic pregnancies, lower initial BMD values, higher fat accumulation and higher early-pregnancy body mass index were associated with lower BMD loss. While gestational diabetic women had higher BMD loss than non-diabetic women, this was apparently secondary to other anthropometric factors rather than due directly to the gestational diabetic state.

Bone status during adolescence, pregnancy and lactation

PURPOSE OF REVIEW

At birth, the fetus will contain 30 g of calcium; during the third trimester the calcium accrual can be up to 340 mg/day. Therefore, extremely high demands for calcium provision are placed upon the mother. This review aims to describe the adaptive mechanisms of the female skeleton to pregnancy and lactation, which ensure optimal fetal skeletal mineralization without compromise to maternal bone strength.

RECENT FINDINGS

Descriptions of changes in bone status during pregnancy and lactation have been published. One of the only studies to measure pre-conception to post-weaning shows complete recovery of maternal spinal bone mineral density (BMD) and near recovery at the hip. Most studies describe trabecular bone loss, but there is evidence for endosteal resorption of the metacarpals. In a retrospective study of former teenage mothers those who breastfed had similar hip BMD to nulliparous age-matched women; those who did not breastfeed had lower hip BMD. Maternal response to low calcium intake differs from that of normal calcium intake.

SUMMARY

Pregnancy and lactation do not have an overall negative effect upon the maternal skeleton. Retrospective evidence suggests no harmful effect of teenage pregnancy if the teenager breastfed, but this requires further investigation. The effects of other situations, for example low vitamin D status or low calcium intake, require further research to inform future clinical practice.