The effects of pregnancy and lactation on hormonal status and biochemical markers of bone turnover.

INTRODUCTION: Biochemical markers of bone turnover are reliable indices for measuring changes in bone formation and bone resorption. Due to limitations in the use of bone densitometry during pregnancy biochemical markers of bone turnover provide an excellent alternative to examine the state of the skeleton during this physiologic state. STUDY DESIGN: We performed a prospective study in 20 women, during their first full term pregnancy until 12 months postpartum, intending to breast feed for 12 (mean, 9.1; range, 7-12) months postpartum. Morning blood and urine samples were obtained for laboratory tests: within 3 months before conception (baseline); between 22 and 24 gestational weeks; after delivery, and 6 and 12 months postpartum. Serum 25-hydroxyvitamin D (25-OH-D), parathyroid hormone (PTH), bone specific alkaline phosphatase, osteocalcin (OC), procollagen I carboxypeptides, calcium, phosphate and creatinine in addition to urine deoxypyridinoline crosslinks and calcium were measured. RESULTS: There was no significant difference in the values of urinary calcium/creatinine and serum calcium, phosphate and 25-OH-D between the different visits during the study. In our patients there was a significant increase in PTH levels at 12 months postpartum as compared to baseline, although the mean values remained in the PTH reference range. All bone turnover markers increased during pregnancy and failed to reach baseline level even 12 months postpartum. CONCLUSION: The high maternal bone turnover may suggest that the calcium needed for infant growth during pregnancy and lactation may be drawn at least in part from the maternal skeleton.

Pregnancy in women with systemic lupus erythematosus.

BACKGROUND: Systemic lupus erythematosus (SLE) is an autoimmune disorder which may be affected by hormonal changes, such as those of pregnancy. Women with SLE have increased adverse pregnancy outcomes. STUDY DESIGN: A retrospective analysis of the gynecologic and immunologic case history of 140 women with SLE and the outcome of 263 pregnancies in 99 women with SLE. RESULTS: In patients diagnosed with SLE, the proportion of pregnancies ending with live birth at term decreased to one-third compared with three quarters in those without a diagnosis of SLE and the incidence of pre-term deliveries and spontaneous abortions increased by 6.8 and 4.7 times, respectively. When SLE was associated with secondary antiphospholipid (APL) syndrome, and lupus anticoagulant (LA) or beta2-glycoprotein antibodies were present, a further increase in the incidence of pregnancy loss was observed. Pregnancy did not cause a flare-up of SLE in all cases, the disease remained stable in about 30% of the patients. Lupus was mild in the majority of the women who carried out their pregnancy to term. We also observed mothers with active SLE who successfully carried out pregnancies to term. CONCLUSION: These findings accord with previous literature and should inform rheumatologists, obstetricians and neonatologists who guide patients in their reproductive decisions.