Table 1 Constituents of the intervention and control drinks
Intervention group | Daily amount | Rationale |
|---|---|---|
Myo-inositol | 4 g | Improves glucose metabolism and preliminary data suggest may maintain healthy glucose metabolism in pregnancy; dose safely used in pregnancy |
Vitamin D3 | 400 IU | Deficiency highly prevalent and linked with glucose metabolism in pregnancy and offspring postnatal adiposity gain; dose sufficient to reduce insufficiency while avoiding potential concerns re adverse effects at high doses. Omission from control group supported by a Lancet study [56] |
Vitamin B6 | 2.6 mg | Deficiency highly prevalent and linked with glucose metabolism in pregnancy and offspring postnatal adiposity gain [33]; dose sufficient to rectify deficiency and present in current over-the-counter products (e.g. Elevit). Omission from control group supported by usual clinical practice |
Vitamin B12 | 5.2 μg | Deficiency highly prevalent and linked with glucose metabolism in pregnancy and offspring postnatal adiposity gain; dose sufficient to rectify deficiency and less than that in current over-the-counter products (e.g. Elevit). Omission from control group supported by usual clinical practice |
Riboflavin | 1.8 mg | Low intake highly prevalent and linked with offspring postnatal adiposity gain [34]; dose sufficient to rectify deficiency and present in current over-the-counter products (e.g. Elevit). Omission from control group supported by usual clinical practice |
Zinc | 10 mg | Deficiency highly prevalent and linked with offspring postnatal adiposity gain [unpublished]; dose sufficient to rectify deficiency and present in current over-the-counter products (e.g. Elevit). Omission from control group supported by usual clinical practice |
β-carotene | 720 μg (15% of vitamin A requirements, as retinol equivalents) | Required in pregnancy in some jurisdictions |
Folic acid | 400 μg | Standard preconception recommendation |
Iron | 12 mg | Iron is routinely prescribed and taken before/during pregnancy, though without convincing evidence of benefit; low dose included to lessen likelihood of additionally receiving a high-dose iron product, which has been linked with glucose metabolism in pregnancy |
Calcium | 150 mg | A low dose of calcium is commonly taken before/during pregnancy; provision of this will lessen the likelihood of additional products being taken |
Iodine | 150 μg | Standard preconception recommendation |
Probiotic | Taking a combination of two probiotics has been linked with maintenance of healthy glucose metabolism in pregnancy. Probiotic capsule containing >1 × 109 cfu each of Lactobacillus rhamnosus NCC 4007 (CGMCC 1.3724) also known as LPR and Bifidobacterium animalis sp. lactis NCC 2818 (CNCM I-3446) also known as Bl818 | |
Control group | ||
Folic acid | 400 μg | Standard preconception recommendation |
Iron | 12 mg | Iron is routinely prescribed and taken before/during pregnancy, though without convincing evidence of benefit; low dose included to lessen likelihood of additionally receiving a high-dose iron product, which has been linked with glucose metabolism in pregnancy |
Calcium | 150 mg | A low dose of calcium is commonly taken before/during pregnancy; provision of this will lessen the likelihood of additional products being taken |
Iodine | 150 μg | Standard preconception recommendation http://www.cdc.gov/preconception/documents/clinical-content_womensnutritionfactsheet3.pdf |
β-carotene | 720 μg (15% of vitamin A requirements, as retinol equivalents) | Required in pregnancy in some jurisdictions |