fp<- babies %>%
mutate(parity_label = fct_recode(as.factor(parity), "first_pregnancy" = "0", "not_first_pregnancy" = "1")) %>%
group_by(parity_label)%>%
summarise(n = n(), mean_gest = mean(gestation, na.rm = TRUE), median_gest = median(gestation, na.rm = TRUE)) %>%
print()
## # A tibble: 2 × 4
## parity_label n mean_gest median_gest
## <fct> <int> <dbl> <dbl>
## 1 first_pregnancy 921 279. 279
## 2 not_first_pregnancy 315 281. 282
Based on the table, there is little difference in the measures and it seems that first pregnancy or not does not matter to the gestation length.