Effect of Calcium Plus Vitamin D Supplementation on Adolescent Mother and Infant Bone Health

Universidade Federal do Rio de Janeiro76 enrolled

Overview

Pregnancy and lactation are periods of high calcium requirement. Inadequate maternal calcium intake and vitamin D insufficiency may adversely affect fetal and neonatal growth and maternal bone mass particularly in adolescent mothers. The investigators propose to evaluate the influence of calcium plus vitamin D supplementation during pregnancy on bone mass of lactating adolescent mothers with habitually low calcium and vitamin D, on fetal growth and neonate bone mass. Mothers are randomly assigned to receive daily calcium (600 mg) plus vitamin D3 (200 IU) supplement or placebo from mid gestation until parturition. Fetal growth parameters are assessed by standard ultrasound techniques at mid and late gestation. Maternal bone mass is assessed by dual energy x-ray absorptiometry (DXA) at 2 and 5 months postpartum and 6 months after weaning. Infant bone mass is assessed by DXA at 2 months postpartum.

Study Type

INTERVENTIONAL

Allocation

RANDOMIZED

Purpose

PREVENTION

Masking

SINGLE

Enrollment

Conditions

Lactation Bone Loss Infant Bone Growth

Interventions

Eligibility

Sex: FEMALEMin age: 13 YearsMax age: 19 YearsHealthy volunteers:

Medical Language ↔ Plain English

Inclusion Criteria: * 13-19 y old * between 23 and 29 wk of gestation * primiparous * carrying single fetus * intending to exclusively or predominantly breastfeed Exclusion Criteria: * chronic health problems * smokers * users of nutritional supplements, except iron supplements provided during standard prenatal care

Outcomes

Primary Outcomes

Differences in maternal bone mass changes postpartum between supplemented and placebo groups

Time frame: 2, 5 and 12 months postpartum

Differences in fetal growth and infant bone mass between supplemented and placebo groups

Time frame: 2nd and 3rd trimester gestation and 2 mo postpartum

Secondary Outcomes

Differences in changes of bone and calcium related hormones and vitamin D status between supplemented and placebo groups

Time frame: 2nd and 3rd trimester of pregnancy and 2, 5, 12 mo postpartum

Differences in human breast milk composition (nutrients and hormones) between supplemented and placebo groups

Time frame: 2 months postpartum

Differences in maternal bone status according to vitamin D receptor (VDR) polymorphisms

Time frame: 2, 5 and 12 months postpartum

Differences in infant body composition between supplemented and placebo groups

Time frame: 2 months postpartum

Differences in changes of maternal body composition postpartum between supplemented and placebo groups

Time frame: 2, 5 and 12 months postpartum