The goal of this observational study is to determine whether the frequency of ejaculation in men had an effect on semen parameters.. The main questions it aims to answer are:

• question 1：Whether the frequency of ejaculation has an effect on semen parameters
• question 2：Whether the penultimate abstinence period has an effect on semen parameters

The participants were men who underwent semen examination in the andrology clinic of the Reproductive Center of the First Hospital of Jilin University. A brief medical history was collected from each volunteer, including demographic information, fertility history and as well as information regarding their general health.The focus of the investigation is the time of abstinence for this examination, the penultimate abstinence period, and the number of ejaculation since the last 1 month.

The main subjects of this study were husbands who underwent semen examination, Including pre-conception, infertility, and his wife with a history of pregnancy loss. Before the examination, the basic information such as age, height, weight, smoking, drinking, infertility years, fertility and pregnancy history, marriage years, education, occupation and exclusion criteria have adverse effects on sperm were investigated.The focus of the investigation is the time of abstinence for this examination, the penultimate abstinence period, and the number of ejaculation since the last 1 month. According to World Health Organization standards, semen analysis requires abstinence for 48h to 7 days. Semen parameters were recorded, including sperm DNA fragmentation rate, sperm motility rate, total sperm count, sperm motility, and sperm morphology. The frequency of ejaculation was divided into four groups:(1)0-4 times/month;(2)5-8 times/month;(3) 8-12 times/month;(4) >12 times/month.

Inclusion Criteria:

1. Normal ejaculation function, normal sexual life, masturbation can ejaculate
2. Male age between 22 and 45 years old.
3. According to World Health Organization standards, the semen examination time is within 48h to 7 days of abstinence.

Exclusion Criteria:

1. The man was diagnosed with extremely severe oligospermia (sperm concentration <1 million/ml) and azoospermia.
2. Identify the factors affecting semen parameters, long-term exposure to high temperature, long-term exposure to chemicals, heavy metals, radiation and other toxic and harmful substances, orchitis/epididymitis, cryptorchidism, radiotherapy and chemotherapy treatment, and taking drugs to improve sperm within three months

The participants were men who underwent semen examination in the andrology clinic of the Reproductive Center of the First Hospital of Jilin University. Including pre-conception, infertility, and his wife with a history of pregnancy loss.