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What is the likelihood of pregnancy during my period?
Last reviewed: 06.07.2025
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When using the "dangerous days" calculation method as a contraception, it is the irregularity of menstruation that should be taken into account. Failures are possible due to overwork, time zone changes, hormonal imbalances, etc. Also little known is the fact that sperm survives up to eight days, so intimacy on the fourth or fifth day of the cycle with subsequent ovulation seven to ten days later increases the likelihood of pregnancy during menstruation.
Normally, a woman’s cycle lasts 21-35 days and is divided into two phases:
- preparatory before fertilization, characterized by active production of follicle-stimulating and luteinizing hormones;
- ovulation.
It is considered ideal when both phases last the same number of days. For example, with a 28-day cycle, each phase is allocated 14 days. An important aspect is the regularity of the monthly cycle (a difference of three days is allowed). The exception will be girls under eighteen years old, whose cycle has not yet been established.
It is believed that pregnancy does not occur only on the first day of menstruation due to the release of a dead egg. On other days, you should remain vigilant and think about reliable methods of protection against unwanted pregnancy.
Possibility of pregnancy during menstruation
The maturation of the egg can occur ahead of schedule, and the lifespan of the sperm after sexual intercourse is up to seven to eight days. Based on these data and the presence of a menstrual failure in a woman, conception is possible a few days after sex on the fifth or sixth day of menstruation. A special risk group is made up of representatives of the fair sex with an irregular cycle, its abrupt changes (lengthening/shortening). The first days of menstruation are considered the safest.
The simultaneous maturation of two eggs in one cycle increases the possibility of pregnancy during menstruation. Such a rare phenomenon is typical for young girls during a hormonal peak due to a strong orgasm, individual characteristics of the body, as a result of a hereditary factor.
There have been situations when bleeding due to stress, cervical trauma was confused with menstruation, and conception occurred. Doctors recommend protection on all days of the cycle, and using a condom during menstruation will protect the uterus from the penetration of pathogenic microorganisms.
It should be remembered that menstruation during pregnancy is not normal. At a minimum, the appearance of blood signals a hormonal imbalance, and at a maximum, it foretells a spontaneous termination of pregnancy. Do not postpone a visit to the gynecologist. With timely treatment, it is possible to preserve the desired pregnancy and give birth to a healthy baby.