The Rh factor in pregnant women

The Rh blood factor plays an important role during pregnancy, especially if the expectant mother is Rh-negative. In this case, there is a risk of Rh incompatibility, which can be dangerous for the health of the woman and the baby.

What is Rh conflict and how does it occur?

About 15% of people have a negative Rh factor (Rh-). If both parents are Rh-, Rh incompatibility is excluded. However, if an Rh- woman becomes pregnant by an Rh+ man (positive Rh factor), the probability that the child inherits Rh+ is about 60%. In this case, there is a risk of immune conflict.

Rh incompatibility occurs when the red blood cells of the Rh+ fetus enter the mother's bloodstream, often at the time of delivery. The woman's immune system perceives these cells as foreign and starts producing antibodies that cross the placenta and destroy the fetus's red blood cells. This can lead to a lack of oxygen for the fetus, an increase in bilirubin levels, anemia, tissue swelling, and other complications.

Why is it important to monitor the negative Rh factor?

Generally, during the first pregnancy, the mother’s blood and the fetus's blood do not mix, and no conflict occurs. However, during delivery or medical procedures, blood contact can happen, causing the mother's body to "memorize" the Rh antigen. In subsequent pregnancies, the risk of Rh incompatibility increases.

Rh- women require special monitoring. Rh incompatibility does not present specific symptoms but can manifest as toxemia or general malaise. An ultrasound that detects an increase in the size of the fetus's liver, spleen, or heart may suggest the presence of a problem.

How to diagnose and monitor Rh incompatibility

To avoid any complications, a comprehensive examination is conducted: the blood type and Rh factor of both parents are determined, medical histories are reviewed, and blood tests are regularly performed to detect the presence of anti-Rh antibodies. The antibody levels are monitored monthly. Depending on their evolution, doctors assess the risk of conflict and the need for intervention.

The Rh factor in natural conception and IVF programs

In the case of natural conception, the risk of Rh incompatibility depends on the combination of the partners' Rh factors. If the woman is Rh- and the man is Rh+, special attention should be given by obstetricians-gynecologists, particularly in cases of repeated pregnancies. In such cases, it is important to monitor antibody levels and use preventive methods, such as the injection of Rh Immunoglobulin just after the delivery of the first Rh+ baby.

In in vitro fertilization (IVF) programs, the risk management approach is similar. In the case of IVF using the patient's own eggs, the Rh factor of both partners is determined. When using donor eggs, doctors strive to find an Rh- donor if the patient is also Rh- to exclude any risk of conflict. In cases of double donation (eggs and sperm from donors), the Rh factor of both donors is selected to ensure maximum safety for the future mother.

Thus, regardless of the conception method, a negative Rh factor requires an individual approach and constant monitoring by specialists.

Prevention and medical care

To prevent risks due to Rh incompatibility, special medications are used that block the production of antibodies. During the first pregnancy, they are administered at 28 weeks, and then within 72 hours after delivery if the child is born Rh+. This measure significantly reduces the risk of complications in subsequent pregnancies.

Specialists at the “Natuvitro” clinic provide qualified assistance during pregnancy, including in cases of negative Rh factor. Women are monitored by experienced obstetricians-gynecologists who consider all possible risks and choose an individualized medical follow-up strategy.