Abstract
Back ground: Vitamin D3 insufficiency is an essential factor effect on many body systems and mechanisms via the receptors of vitamin D3 (VDR) which is found in multiple organs, one of them is reproductive systems affecting the fertility of women.

Objectives: Management of vitamin D3 insufficiency can ameliorate pregnancy rates in the subfertile females.

Patients and Methods: This is a randomized interventional clinical trial. In which Serum vitamin D3- 25-(OH) level of 90 women who had undergone fertility treatment cycle was checked. 86 women with insufficient serum vitamin D (< 30 ng/ml) were included in our analysis. 43 females were managed with 50000 IU vitamin D3, supplementation weekly, for six to eight weeks (group I) and 43 females without treatment (group II-control). Pregnancy rate represent our outcome.

Results: Our trial show significant statistical increase in the pregnancy rate (44.26%) in subfertile female after vitamin D3 supplementation (p=0.0007) and RR (relative risk)=3.7999.

Conclusion: Management of vitamin D insufficiency is significantly improved pregnancy rate of subertile women.

Key words: Vitamin D, Subfertility, Pregnancy Rate.