I am trying to add an empty row to an existing populated Dataframe.  

I am using the below procedure for this, but I do not want to see NA values in the empty row, just need some blank row. 

Existing data frame: 

```
abc
site control    test delta   pval  
1 US15376   3.15% 3.2% 1.59% 0.0022

```

empty matrix: 

```
empty=matrix(c(rep.int(NA,length(abc))),nrow=1,ncol=length(abc))  
colnames(empty) = colnames(abc)  

rbind(abc, empty)
    site control test delta   pval  
1 US15376   3.15% 3.2% 1.59% 0.0022  
2    NA    NA NA  NA     NA  

```

Can anyone help me with this?