delayed periods have something to do with receiving oral sex

Hi,
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If semen or pre-cum has come in contact with vagina (genital contact or fingering), chances of pregnancy are possible (especially if the girl is during her fertile days at time of sexual contact). Variation of 5-10 days in menstrual cycle length is considered to be normal. Look out for development of any new symptoms if pregnancy is suspected. She should visit her gynecologist for further evaluation and assistance if she does not get her periods within 10 days of expected period dates, or gets abnormal bleeding. If pregnancy gets ruled out and if she is not ready for pregnancy, but intends to remain sexually active, she should consider getting started on suitable regular birth control measures to be protected (after her periods). She should be regular with birth control use as instructed. She should avoid having unprotected sexual contact if not ready for pregnancy.
Take care.