**2.1 Study design**

This case–control research comprised 30 pregnant women and 30 non-pregnant women who visited Al-zahraa Teaching Hospital's outpatient clinic on a regular basis. As a result of a randomized selection (where every member of a population has an equal probability of being included in the sample and where all feasible samples of a given size have an equal probability of being chosen), selected participants were assessed individually using a plate form questioner and agreed to participate in this study for three months, starting in July and ending in September 2019.
