ggplot the coef with 95%CI, by group

Question

I would like to use ggplot to plot my result of the association of air pollutant with birth weight changes (95%CI).

the format of my data is like this

variable    exposure period      coef    coef_lb      coef_ub
PM10        entire pregnancy    -27.6      -49.2         -3.8
SO2         entire pregnancy       40       14.2         62.8
NO          entire pregnancy      -26        -44         -6.4
NO2         entire pregnancy        0        -20           19
PM10        trimester1          -29.4      -49.4           -8
SO2         trimester1             12         -9         31.8
NO          trimester1            5.2      -15.2         28.2
NO2         trimester1           -2.2        -23         16.6
PM10        trimester2          -11.8      -35.2         11.2
SO2         trimester2           26.2          2         51.4
NO          trimester2          -10.8      -35.2         12.4
NO2         trimester2           -7.4      -27.8         14.6
PM10        trimester3            6.2      -17.6         28.2
SO2         trimester3            0.6        -19         22.4
NO          trimester3            -24        -43         -5.4
NO2         trimester3              7      -11.4         26.8

I have four types of air pollutants, exposure period is trimester-specific, and I have the coef, and the lower bound and upper bound of 95%CI.

I want to plot a graph like the one below, can anyone help?

Answer 1

#get the data.frame
data <- read.table("DATA.csv",header=T,sep=";")

require(ggplot2)

#build and plot ggplot object
g <- ggplot(data=data,aes(x=exposureperiod,y=coef))
g <- g + facet_grid(.~variable)
g <- g + geom_errorbar(aes(ymin=coef_lb,ymax=coef_ub))
g