Preconception sex determination: Maternal demographic variables as a predictive “tool”

Background: The unending attempt targeted at having a particular sex has led to unplanned increase in family sizes, especially in the developing world. Most published studies on sex selection did not consider the effects of maternal variables. Objective: The main objective of the study is to investigate the effects of maternal variables: age, date of the last menstrual period (LMP), blood group, and genotype on the sex of a baby. Materials and Methods: One hundred and twenty-seven case files of women who attended the Antenatal and Postnatal Clinics at the Lagos University Teaching Hospital, Idi-Araba, Lagos, between 2013 and 2015 were randomly selected. They comprised women between the ages of 18 and 40 years. Data extracted were maternal age, LMP, blood groups, and genotypes of mothers and sexes of their babies. Results: The percentages of boy (38.4%) to girl (9%) child born to mothers with LMP occurring in 1st week (day 1–7) of the month were significant (P < 0.05) compared to 2nd, 3rd, and 4th week, with male-to-female percentages of 12.3%–25.9%, 15.1%–24.1%, and 34.3%–33.3% (P > 0.05), respectively. There was no association between genotype and blood groups of the mothers and the sex of the baby (P > 0.05). Conclusion: The study showed correlations between the sex of the infants and the week of the month of LMP supporting maternal involvement in sex determination.