It is a highly relevant topic, a frequently asked question. Yet, there are almost no clinical studies on the topic. Science has still not seriously explored this realm.
So, this article tries to identify the influences of active sex life on the menstrual cycle and hormonal health – from a scientific point of view.
Needless to say, the most significant thing that can occur due to sex is pregnancy, which may result in temporary discontinuation of the menstruation cycle. However, here we are not interested in this topic. Our prime area of interest is how can being sexually active affects the menstrual cycle.
Although science may not have studied this topic much, there are some indicators that sexual activity can affect hormonal health and periods.
That is why no surprise that in many cultures, it is said that having regular sex is vital for good health. Even science also confirms that, to a degree, intimacy is good for well-being, and it even appears to extend life.
Moreover, sex is more than just physical contact between individuals. It is lots more for most people. It is about relaxation, enhancing relationships, improving intimacy, and more.
Below are some scientific reasons to believe that sexual activity can influence menstrual cycles:
You lose what you do not use
First and foremost, it is vital to understand that “you lose what you do not use”. The human body quickly starts getting rid of those functions that remain unused. This allows the body to be more efficient and focus resources on other important functions.
Thus, if you do not jump or run, it becomes tougher—sedentary lifestyle results in loss of lean mass. Additionally, the body has a robust negative feedback system, which removes anything in excessive amounts, including hormones. This negative feedback ensures homeostasis or balance in the body.
Thus, if you do not have sex at all, naturally, negative feedback will send certain signals to the brain and endocrinal organs. They will be instructed to produce fewer hormones and not focus much on reproductive health. Lack of sex sends signals to your brain that sexual or reproductive health is not your priority.
Though this topic of the relationship between sexual activity and menstrual cycle is not fully explored by science, nonetheless, there are some sound studies. Much evidence comes from studies of various other hormones and body systems. If you do not use them, they start losing their ability to work properly.
There have been studies that show that sexual activity influences sex hormone levels. One study on 259 regularly menstruating women aged 18-24 found that sexual activity affects hormones.
The study found that whenever these women had sex, this increased estrogen and luteal progesterone levels by about 15%, compared to sexually inactive women!1 They tested their hormone levels eight times during each cycle to ensure their findings were relevant.
Of course, this study did not monitor menstrual cycle regularity. Nonetheless, it confirms one important thing. It establishes the basic principle of physiology.
If you are sexually active, hormone levels increase. Sexual inactivity reduces hormone levels. This might not have a short-term impact on the cycle but may start influencing it in the long run. Thus, have sex regularly for regular menstrual cycles.
Sexercise, health, and the cycle
There is much research on the benefits of exercise for sexual health. Regretfully, there is little research regarding sex as an exercise. Nevertheless, one cannot negate that sex/arousal causes a person to breathe faster and makes the heart beat faster – it is a moderate-intensity exercise. Its benefits start with foreplay.
Regular physical activity is known to help regularize cycles. Physical fitness affects sexual health and vice-versa. Therefore, there is a reason to believe that regular sex can help normalize menstrual cycles.
Of course, this also means that many women may notice some changes in the menstrual cycle when they increase their relative sexual activity. Most women notice such changes when they start having regular sex after a prolonged period of abstinence.
Sex has numerous health effects, thus may influence menstrual cycle
Again, it is no secret that lifestyle changes and specific emotions influence menstrual cycles. Sex can help relax, reduce anxiety, make a person happier, boost immunity, improve brain health, enhance sleep quality, and so on. 
All these factors may affect the menstrual cycle in some women. Regretfully, there are no studies on the subject. Nonetheless, there is a strong reason to believe in this. Moreover, people have observed many such things.
Further, orgasm is still not a fully understood phenomenon. Nonetheless, it is known that orgasm causes significant hormonal changes.
It may reduce stress hormones. Orgasm also results in increased production of certain hormones and beneficial chemicals. Frequent orgasms may influence even the working of the brain. 
The bottom line
Regular sex is good for physical health, hormonal health, and mental well-being. It can definitely influence menstrual cycles in more than one way. Of course, how much it affects would differ and depend on many factors like age, sex frequency, genetics, and more.
Thus, some may experience changes in their menstrual cycle even after intense sexual activity for a few days. Others after prolonged or regular sexual activity for weeks.
Additionally, observations also suggest that sexual activity in marital settings or with someone with whom a person has strong emotional bonding may result in more significant benefits. Since such sex is not just about fluctuations in sex hormones, it is about changes in the brain’s activity, neurotransmitters, mood, and more.
Therefore, it would be right to say that to stay young for longer, have sex regularly. But, of course, due to individual differences, the definition of regular sex may differ.
For some, it may be once a day; for others, it is once fortnightly. It also means listening to your body. Additionally, as already said, focus on developing healthy relationships, as they have a greater influence on well-being and consequently on the menstrual cycle.
- Prasad A, Mumford SL, Buck Louis GM, et al. Sexual activity, endogenous reproductive hormones and ovulation in premenopausal women. Horm Behav. 2014;66(2):330-338. doi:10.1016/j.yhbeh.2014.06.012
- Adaikan PG. AB59. Can sexual health contribute to longevity? Transl Androl Urol. 2014;3(Suppl 1):AB59. doi:10.3978/j.issn.2223-4683.2014.s059