How many donor sperm units should I buy for one child?

There is no single answer. Begin by identifying your treatment type and plan for 3 to 4 treatment cycles unless your clinic advises otherwise.

Do I need more units for insemination than for IVF?

Usually yes. Insemination often involves planning several treatment cycles, while IVF commonly starts with one unit plus a backup unit.

Should I reserve extra units for future siblings?

Yes, if having genetically related siblings is important to you. Reserving extra units early can help protect future options with the same donor.

Fertility Education

How Many Donor Sperm Units Should You Buy to Have One Child?

By Dr. John K. Jain, MD

Starting your fertility journey is an exciting step. One of the most common questions patients ask is how many units of donor sperm they need to purchase.

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Because every patient is unique, there is no universal magic number. The most important factors in determining how many units to purchase are your age, your fertility status, and the type of treatment you are undergoing.

We recommend consulting your gynaecologist or fertility specialist before getting started to better understand your individual chances of success. However, the guide below can help you plan.

Understanding Success Rates

Donor sperm can be used for insemination or for IVF treatment, and success rates vary based on the method and your age.

Insemination success rate:

If you are under age 35: approximately 18 percent chance of a live birth per cycle.
Ages 35-40: the rate drops slightly to 10-15 percent per cycle.

Cumulative birth rates are calculated using actuarial methods, rather than simply multiplying your chance of success by the number of months you try.

Following this approach, the cumulative birth rate for women under 35 doing insemination approaches 75 percent after six cycles. For women aged 35-40, the six-month cumulative rate is roughly 50-65 percent.

IVF success rates are generally higher per treatment cycle than insemination rates, but they still vary significantly with age and clinical circumstances.

As a practical rule, many patients plan insemination and IVF separately because the number of units required changes depending on whether treatment stays with insemination or progresses to IVF.

So, How Many Units Should You Buy?

As most successful pregnancies occur within the first 3 to 4 months of trying, we generally recommend planning for 3 to 4 treatment cycles upfront and reassessing with your doctor if you are not yet pregnant.

Here is what this may look like depending on your treatment:

For Insemination

Plan for 3-4 units. You will typically use 1 unit per treatment cycle.

For IVF

Plan for 2 units. One unit is usually needed for the treatment cycle, and a second unit is recommended as a backup in case of laboratory issues or a later retrieval.

If your chosen donor has good availability, you may choose to purchase units month by month. However, popular donors can sell out quickly, so buying enough units for 3 to 4 treatment cycles upfront can help avoid having to change donor during your journey. Keeping a small reserve is also recommended to protect against shipping delays, laboratory issues, or limited future availability.

Planning for Multiple Children

If you would like biologically related siblings using the same donor, it is advisable to purchase additional units for frozen storage, either at Premier Sperm Bank or at your clinic.

Please keep in mind that success the first time does not automatically guarantee the same outcome in the future, particularly as many women are 2-3 years older when trying to conceive their next child.

If you succeed with insemination, purchase enough units to allow for future insemination treatment cycles and consider reserving at least 1 additional unit for IVF should a more advanced treatment option be needed later.

If you succeed with IVF and have frozen embryos remaining, you already have a strong starting point. Even so, keeping at least 1 backup unit of sperm in storage is a sensible precaution in case an embryo does not survive thawing or fails to implant.

Two young siblings playing together on a bedroom floor.

Frequently Asked Questions

Choosing the Right Type of Sperm Unit

Sperm banks often use terminology such as washed vs. unwashed, MOT values, and volume sizes. To keep it simple, focus on whether the sperm is washed (IUI) or unwashed (ICI), and how many motile sperm cells are available.

Treatment guide at a glance

Always check with your clinic first, but these are the general rules

Keep the decision simple: confirm whether your treatment calls for washed or unwashed sperm, then make sure the MOT level gives your clinic enough motile sperm cells to work with.

IUI sperm (washed) can be used for all types of treatment.

ICI sperm (unwashed) can also be used for all types of treatment, as your clinic's laboratory can prepare and wash the sample before use.

Because washing may reduce the number of sperm cells, we recommend choosing a higher MOT when purchasing ICI sperm compared to IUI sperm.

MOT indicates the number of million motile sperm cells per millilitre. Each unit contains 0.5 ml, so a MOT20+ unit contains at least 10 million motile sperm cells.

MOT20+ at Premier Sperm Bank

Most units at Premier Sperm Bank are MOT20+. Studies show that for insemination you generally need MOT10+, and even fewer sperm are required for IVF or ICSI.

Using MOT20+ units ensures that you have more than enough motile sperm for treatment and provides additional peace of mind.

Whether you're just beginning to explore donor options or are ready to move forward, we are here to guide you with personal, one-to-one support.

From choosing the right donor to navigating practical steps such as delivery, we're here to make your journey as smooth and reassuring as possible.

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