Bone Abstracts

Objectives: High prevalence (20%) of adolescent pregnancy (AP) (1) is observed in India. Reports suggest that pregnancy during adolescence may have deleterious effects on peak bone mass (2). Few reports have described the long-term effects of history of AP on bone. The objective of this study was to compare bone density and geometry of premenopausal women having delivered first child during adolescence (before age of 19 years) or after 19 years.

Methods: A cross-sectional study was conducted in 242 women (aged 28–54.5 years) from Pune, India (November-2015 - November-2017). Women were divided into 2-groups: Group-1: women who had 1st pregnancy before 19-years of age (adolescent pregnancy-AP) (n=131) and Group-II: women who had 1st pregnancy after 20-years of age (non-AP) (n=111). Demographic data, anthropometric measurements and biochemical tests were performed using standard protocols. Physical activity and nutrient intakes were recorded using standardised questionnaires. Bone mineral density and bone geometry were measured using iDXA (Lunar iDXA, GE Healthcare) and pQCT (XCT2000, Stratec Inc.).

Results: Mean age of the study group was 37±4.6 years. Group I women (age at first delivery 17±1.6 yrs) were compared to group II women (22.6±3.1 years). Socio-economic status and physical activity during adolescence and at time of measurement were similar in the groups. Both groups were similar in BMI, calcium intake, physical-activity, 25 (OH)D and PTH concentrations (P>0.1). DXA measured femoral neck bone density in group I was higher (0.908±0.1 vs 0.878±0.1 g/cm², (P<0.05)). pQCT measurements indicated that cortical thickness at radius in Group I (1.99±0.49 mm) was significantly higher than in group II (1.89±0.27 mm, P<0.05) as was the periosteal circumference (38.03±3.57 mm vs 36.64±2.49 mm, respectively) and total bone area (247.8±34.2 vs 232.7±28.7 mm² respectively). Thus, Group I women had wider bones.

Conclusion: Our data suggest that women who had adolescent pregnancies had wider bones with increase in periosteal bone deposition and bone area. We speculate that increase in pregnancy induced higher levels of estrogens during adolescence may have rendered the bones more sensitive to loading.

Disclosure: The authors declared no competing interests.