Is the chance of getting pregnant high if having sex 8 days before menstruation?
Nov 15, 2025
Source: Cainiu Health
Dr. Zhang Lu
Introduction
If the menstrual cycle is regular (e.g., 28–30 days), ovulation usually occurs approximately 14 days before the next menstrual period. Eight days before menstruation, the ovulation period has typically already passed, and the egg has lost its ability to be fertilized; thus, the likelihood of pregnancy during intercourse at this time is low. However, it should be noted that even with a regular cycle, slight variations may occur due to factors such as emotional state or stress, potentially delaying ovulation and leaving a small chance of unintended pregnancy.
Generally, the likelihood of pregnancy from intercourse 8 days before menstruation is relatively low, but not entirely impossible. The exact probability depends on the regularity of the menstrual cycle. If in doubt, it is advisable to consult a healthcare provider in advance. Detailed analysis is as follows:
If the menstrual cycle is regular (e.g., 28–30 days), ovulation typically occurs around 14 days before the next period. Therefore, 8 days before menstruation usually falls after the ovulation phase, by which time the egg has likely lost its ability to be fertilized, making pregnancy less likely. However, it's important to note that even in regular cycles, factors such as emotional stress or pressure may cause slight variations, potentially delaying ovulation and leaving a small chance of unintended pregnancy.
If the menstrual cycle is irregular, ovulation timing can be unpredictable, and ovulation may occur as late as 8 days before menstruation. If the egg is still viable at this time, fertilization can occur following intercourse, significantly increasing the chance of pregnancy. In such cases, the risk cannot be considered low based solely on the timing of "8 days before menstruation."
If menstruation is delayed by more than 7 days after intercourse 8 days prior to the expected period, a pregnancy test using an early-detection urine test strip can provide initial results, or a blood test at a hospital can confirm pregnancy. For individuals not planning a pregnancy, effective contraception is recommended during every act of intercourse to prevent unintended pregnancy and related complications.
