Paternal Genes Heavily Influence Pregnancy, Surgeon Reveals

According to a report published on August 28, 2025, Dr. Karan Rajan, a UK-based NHS surgeon and popular health content creator, has shed light on the crucial role of paternal biology and genetics in pregnancy. The surgeon stresses that despite the biological reality, society still continues to view pregnancy as solely the woman's responsibility and burden.

Dr. Rajan explains that one of the most crucial aspects of pregnancy, placental formation, is largely driven by the father's contribution, as it is primarily influenced by paternal genes. He compares pregnancy to an "aggressive land grab situation," where the maternal immune system fights off the foreign placenta, and the paternal genes push for more fetal growth.

The surgeon further elaborates that the placenta is not a gentle or passive organ; it actively embeds itself into the mother's uterine lining to secure the nutrients the fetus needs. This "almost parasitic entity" can lead to pregnancy complications like preeclampsia, which are considered "failures of paternal biology."

Dr. Rajan emphasizes that since placental formation is heavily influenced by the father's genes, paternal genes can also influence gestational diabetes, miscarriages, and even fetal growth restriction. He highlights that sperm take roughly three months to fully develop, making a healthy preconception period essential for men to optimize their diet, sleep, stress, and environmental exposures to ensure the health of the placenta and the fetus.