Having intercourse after ovulation will not affect the fertilization of the fertilized egg. Whether the fertilized egg can be successfully fertilized after ovulation is mainly affected by the following factors: 1. whether the estrogen and progesterone levels in the female body are normal. Only if the estrogen and progesterone levels are normal will the endometrium of the female uterus maintain its normal thickness and accommodate the fertilized egg. After the fertilized egg has been laid, it will grow and develop normally under the effect of estrogen levels. 2. whether the fallopian tubes are open, whether the cilia of the fallopian tubes are swinging and whether the peristalsis of the fallopian tubes is normal. If the fallopian tubes are not open or have abnormal peristalsis, it will cause a tubal pregnancy. 3. If the endometrium is too thin or has abnormalities such as adhesions and polyps, it will affect the fertilized egg’s implantation and lead to miscarriage.