Do Blood Groups Matter When Trying to Conceive?

BySamradni Pradhan
Updated: 6 Jun 2025, 11:07 am

If you're trying to get pregnant, you might ask if your blood group or your partner's could be a factor. Blood group does not often impact the ability to conceive, but it is a potential consideration for things like a partner's immune system, risks in pregnancy, and compatibility. The blog explores the potential impact of blood group on fertility and provides valuable guidance to support your fertility journey.

Pregatips.com
Trying to conceive or preparing for pregnancy involves more than just tracking ovulation and hormone levels. Among the many factors that can influence fertility and pregnancy health, your blood group and your partner’s may also play a role. But how exactly does it matter?
In this article:

Blood group indeed plays a role in various health-related issues. It can affect certain aspects of conception, growth within the uterus, and foetal development.

Understanding Blood Groups: The Basics

Your blood group will fall under one of these four groups: A, B, AB, or O. The presence or lack of particular antigens on the outer surface of your red blood cells is what decides them. In addition, blood is classified as Rh-positive or Rh-negative based on whether the Rhesus factor is present.A person can be described as A-positive (A+) or O-negative (O–). You receive your blood group from your biological parents, and it never changes over time.Certain cases of incompatible blood groups during pregnancy can involve the Rh factor and, to a lesser degree, the ABO group.Laboratory testing to determine blood group and Rh factor typically involves blood typing methods, and in some specialised cases, techniques like electrophoresis are used to analyse blood proteins and provide detailed blood group information.

1. Does ABO Blood Group Affect Fertility?

The ABO group is the first thing to look at. Being A, B, AB, or O blood group does not stop you from getting pregnant on its own. Some studies have also investigated whether blood group may be associated with egg production (ovarian reserve) or hormonal levels.

2. Rh Factor: Why It Matters More Than You Think

The Rh factor is where the blood group becomes more medically significant. As Rh-negative parents, you might pass the Rh-positive trait on to your child. This results in what is called Rh incompatibility.Here's how it works:
  • If the mother is Rh-negative and the father is Rh-positive, the baby can be either Rh-positive or Rh-negative.
  • If the baby is Rh-positive, the mother’s immune system may recognise the baby’s blood cells as foreign and produce antibodies against them.
What to do about it:Modern medicine has a highly effective way to prevent Rh incompatibility from becoming an issue. If you're Rh-negative, you'll likely receive an injection of Rh immunoglobulin (RhIg or RhoGAM) around the 28th week of pregnancy and again after birth if your baby is Rh-positive. This prevents your body from forming those harmful antibodies.

3. What About ABO Incompatibility Between Partners?

Just as with Rh factor, ABO incompatibility can occur between a pregnant individual and their foetus. For example, if you have the O blood group and your baby has A or B blood (inherited from the other parent), your body might produce antibodies against the baby's blood cells.However, ABO incompatibility tends to be much milder than Rh incompatibility. In most cases:
  • It doesn't affect fertility or implantation.
  • If a reaction occurs, it's usually limited to mild jaundice in the newborn, which is easily treated.
Fertility impact:ABO incompatibility is unlikely to affect your ability to conceive. It's more relevant during or after delivery and is rarely a cause for concern in modern obstetric care.

4. Could Blood Group Influence IVF Success?

Ongoing research is investigating whether blood group influences IVF (in vitro fertilisation) outcomes, specifically in terms of embryo quality and implantation rates. Some studies suggest small associations; for example, people with blood group A might have slightly better outcomes in certain settings, but the evidence remains inconclusive.Fertility clinics generally do not use blood group as a determinant in IVF protocols or embryo selection.When it comes to fertility, other factors have a greater impact than blood group, including:
  • Age
  • Hormone levels
  • Uterine health
  • Lifestyle factors (like nutrition, smoking, stress)
Note: Ongoing studies in this area have not yet yielded definitive conclusions.

5. Should You and Your Partner Compare Blood Groups Before Trying to Conceive?

It can be helpful to know both your and your partner's blood groups, mainly to understand your Rh compatibility. It's a simple blood test and is usually part of early prenatal care.Here's why it's useful:
  • If both of you are Rh-negative, there is no incompatibility risk.
  • If you're Rh-negative and your partner is Rh-positive, RhIg will be needed during pregnancy.
  • If you're unsure, testing early can help you prepare for any preventative steps.
However, you don't need to be overly concerned or delay trying to conceive based on blood group alone. These are manageable medical factors, not barriers to pregnancy.

What You Can Do Next

Understanding your blood group is one more way to take charge of your reproductive health. It doesn't define your fertility, but it provides useful context, especially regarding Rh compatibility and planning for pregnancy.Here's how to move forward:
  • Ask your provider to confirm your blood group and Rh factor.
  • If you're Rh-negative, be proactive in discussing RhIg and future pregnancies.
  • Keep blood group in perspective. Focus on other fertility signs and general health, including cycle tracking, hormone testing, nutrition, and lifestyle habits.
Your blood group is a fascinating detail. For most people, blood group doesn't stop conception or lead to fertility problems. The Rh factor is the exception and should be managed with your care team during pregnancy, not before.

FAQs - Frequently Asked Questions on Whether Blood Groups Matter When Trying to Conceive

  1. Can Rh incompatibility affect my ability to conceive?Rh incompatibility doesn't prevent conception. It becomes relevant during pregnancy, specifically when the fetus has a different Rh status than the mother. Even then, it's easily managed with Rh immunoglobulin injections.
  2. Should I avoid certain partners based on blood group?No. While blood group compatibility may affect pregnancy management (especially with the Rh factor), it's not a reason to avoid trying to conceive with a partner. Modern medicine provides effective solutions to mitigate potential risks.
  3. Does blood group affect miscarriage risk?In rare cases, immune reactions related to Rh or ABO incompatibility can contribute to miscarriage. However, these are uncommon and usually preventable with early medical intervention.
Disclaimer: Medically approved by Dr Gayathri Dinesh Kamath, Additional Director Obstetrics & Gynaecology, Fortis Hospital Bannerghatta Road