[1] The immunological system of the mother plays an important role in pregnancy considering the embryo's tissue is half foreign and unlike mismatched organ transplant, is not normally rejected.
[2] The placenta also plays an important part in protecting the embryo for the immune attack from the mother's system.
[7][8] This shows a parallel in pregnancy and cancer; both grow and divide at incredibly fast rates without target from the human immune system.
[11] An insufficiency in the maternal immune system where the fetus is treated as a foreign substance in the body can lead to many pregnancy-related complications.
The maternal immune system, specifically within the uterus, makes some changes in order to allow for implantation and protect a pregnancy from attack.
[20][21] uNK cells secrete transforming growth factor-β (TGF-β) which is believed to have an immunosuppressive effect through modulation of leukocyte response to trophoblasts.
Studies have shown that there is a bad compatibility between specifically maternal KIR AA and fetal HLA-C2 which leads to recurrent miscarriage, preeclampsia and implantation failures.
[23] FDA established labeling request for drugs and biological products with medication risks, allowing informed decision making for pregnant and breastfeeding women and their health care providers.
For example, within antibiotics, penicillin may be used during pregnancy, whereas tetracycline is not recommended due to potential risk of fetus for a wide range of adverse effects.
[30] The use of low dose aspirin may be linked to increased rates of live births and fewer pregnancy losses for people who have had one or two miscarriages.
[31] The National Institute of Health has recently changed their stance on using low dose aspirin, stating "low-dose aspirin therapy before conception and during early pregnancy may increase pregnancy chances and live births among a person who has experienced one or two prior miscarriages.
[33] The reasoning behind the change was the determination that adherence to the medication and not discontinuing low dose aspirin due to side effects "could improve the odds for pregnancy and live birth in this group of people.
[34] Some studies have found that using both aspirin and heparin can increase the rate of live birth in a person with antiphospholipid syndrome.
Anti sperm antigen has been described as three immunoglobulin isotopes (IgG, IgA, IgM) each of which targets different part of the spermatozoa.
Infertility after anti-sperm antibody binding can be caused by autoagglutination, sperm cytotoxicity, blockage of sperm-ovum interaction, and inadequate motility.
Normally, spermatozoa fuse with the zona pellucida surrounding the mature oocyte; the resulting acrosome reaction breaks down the egg's tough coating so that the sperm can fertilize the ovum.
This results in the production of antibodies against the ZP, which stop the sperm from binding to the zona pellucida and ultimately from fertilizing the ovum.
[38] Studying the female reproductive tract, especially in humans, allows for a better understanding of the immune system, including during pregnancy.
However, studying the female reproductive tract has been a challenging area of research due to existing limitations in the in vitro and in vivo tools available.
[39] Other studies have concluded that with further technological advancements, it is possible to create a detailed 3D organoid model of the female reproductive tract which introduces a more efficient method to conduct research and collect data in the fields of drug discovery, basic research and essentially reproductive immunology.
This unique feature of the maternal-fetal interface suggests that the decidual immunome, or the immune function of the female reproductive tract, is not fully understood, yet.
Technological advances allow reproductive immunologists to collect increasingly complex data at a cellular resolution.
Polychromatic flow cytometry allows for greater resolution in the identifying novel cell types by surface and intracellular protein.