Purpose: The aim of this study was to assess preconception knowledge and practices and its effect on birth outcomes among puerperal women in the Tamale Teaching Hospital.Methodology: The study employed analytic cross-sectional study design with a quantitative approach. A semi-structured questionnaire was used where questions on knowledge of preconception were adopted from Southampton Women’s Survey, 2006. Puerperal women in the postnatal unit of the Tamale Teaching Hospital, who were yet to be discharged, including referred cases, were selected as target population for this study. The exclusion criteria were women who have never delivered and menopausal women. The sample size was 363 puerperal women. Purposive sampling method was used to attain the required sample. Data was analyzed using SPSS version 25. In the analyses, a p-value<0.05 was considered statistically significant when variables were cross-tabulated.Findings: The results of the study revealed a high proportion of puerperal women 161 (44.3%) were above 30 years. The mean age was 30.56±6.44 years. The study found that 37.2% women had knowledge on preconception care. There was a significant association between folic acid intake and postpartum haemorrhage (r=-0.183, p<0.0001). There was no statistical association between birth outcomes and concurrent loss of pregnancy and number of pregnancies lost except for birth weight (r=0.202, p=0.000). Albeit preconception care knowledge was low among puerperal women, it significantly influenced postpartum haemorrhage and pregnancy induced hypertension but not antepartum hemorrhage and birth weight.Recommendation: At the community level the study recommended to the Ghana Health Service that a mother-to-mother support group be formed among women in their reproductive age and this could help encourage one another to discuss about their health before pregnancy and share success stories on birth outcomes and report to the facility in case of any problems.