Hello, You are suffering from rash on the butt crack. It is itchy and uncomfortable. You are pregnant. Hormonal changes during pregnancy can be cause rashes, excessive dryness (zero moisture content) on the part of the skin also causes rashes. Butt crack rashes are characterized by itchiness on the part of the skin. You are suggested to stay adequately hydrated and apply water based body lotion after bathing to prevent skin from getting dry. You can apply Soframycin lotion on the area affected for relieve. Applying cold compress may help. Butt crack rash can be a symptom of other infections that can be fungal. You can apply Clotrimazole cream on the area affected in case of fungal infection. Get clinically examined by your Gynae or health care provider. You will be accordingly treated. Take care of your hygiene, take bath regularly & wear loose fitting soft cotton clothes. Take care. Hope I have answered your question. Let me know if I can assist you further. Regards, Dr. Nupur K., General & Family Physician