An egg and sperm are fertilised when they unite to form a fertilised egg, also known as a zygote. Human creation begins with this step.
Fertilization requires that sperm reach and fertilise the egg. What is the required number of sperm for this process? In this article, we will discuss the average sperm count and the factors that can affect it.
Sperm count and fertility
Men’s sperm count is an indicator of their sperm count inside their semen. Fertility is the ability to conceive and have a child. The average sperm count needed for fertilisation is about 15 million per millilitre of semen.
However, it is important to note that having a low sperm count does not necessarily mean that a man is infertile, as other factors such as sperm motility (movement) and morphology (shape) also play a role in fertility.
There are several factors that can affect sperm count and fertility, including:
- Age: As men age, their sperm count and motility may decline.
- Lifestyle: Factors such as smoking, alcohol consumption, and drug use can negatively impact sperm count and fertility.
- Diet: A diet high in processed foods and low in essential nutrients can negatively impact sperm health.
- Environmental toxins: Exposure to certain chemicals and pollutants can also affect sperm count and fertility.
- Medical conditions: Certain medical conditions such as varicocele, a condition in which the veins in the testicles are enlarged, and hormonal imbalances can also affect sperm count and fertility.
- Medications: Certain medications, such as antidepressants, blood pressure medication, and anabolic steroids, can also negatively impact sperm count and fertility.
- Obesity and lack of physical activity
- Exposure to heat (such as from hot tubs or saunas)
It’s important to note that some of these factors can be treated or managed, and men with concerns about their sperm count and fertility should consult with a doctor or fertility specialist for guidance.
How many sperm are needed for fertilization?
Approximately 15 million sperm are needed per milliliter of semen for fertilisation. The fact that a man has a low sperm count does not necessarily mean he is infertile, however.
The minimum number of sperm needed for fertilisation is not well defined. Some studies have shown that as few as 40,000 to 60,000 sperm per millilitre can be enough for some couples to conceive.
The probability of fertilisation with a low sperm count, also known as oligospermia, can vary depending on several factors, such as the sperm’s motility, morphology, and quantity of semen.
Men with a sperm count below 10 million per millilitre are considered to have a low sperm count. However, some men with a low sperm count are still able to father a child naturally.
For couples with low sperm counts, assisted reproductive technologies, like intrauterine insemination (IUI) and in-vitro fertilisation (IVF), can increase their chances of conceiving.
The role of sperm in fertilisation
The journey of sperm to the egg
- Sperm are produced in the testes and are released into the vas deferens during ejaculation.
- The sperm then travel through the vas deferens and into the urethra.
- From there, they are ejaculated out of the body and into the female reproductive tract.
- Once in the female reproductive tract, the sperm must navigate through the cervix and uterus to reach the fallopian tubes.
- In the fallopian tubes, the sperm must overcome various obstacles, such as cervical mucus and the fimbria, before reaching the egg.
- Once the sperm reaches the egg, it must successfully penetrate the egg’s protective outer layer, the corona radiata, in order to fertilize it.
The process of fertilisation
- Fertilization is the process by which a sperm and an egg fuse to form a zygote.
- It happens during sexual reproduction, but it can also happen through artificial means like in vitro fertilization.
- Sperm must navigate through the female reproductive tract and penetrate the egg’s protective outer layer.
- Sperm releases genetic material, which combines with the egg’s genetic material to form a new organism.
- The process of fertilisation can also be referred to as conception.
Fertilization requires that sperm and egg combine successfully. The average number of sperm per millilitre of semen required for fertilisation is around 40 million, but an insufficient number doesn’t necessarily mean nothing can be fertilized.
Factors such as age, lifestyle, and overall health can all play a role in sperm count and fertility. The minimum number of sperm required for fertilisation is around 40,000 to 60,000, but the probability of fertilisation increases with a higher sperm count.
If you are trying to conceive, it is important to consult with a doctor for personalised advice regarding fertility and to understand that sperm alone is not the only cause of infertility; other reasons may exist, such as problems with the egg or uterus.