Neonatal hydrometrocolpos (HMC) is a rare Mullerian duct anomaly with an 
incidence of 0.006%. It occurs due to blockage of the vagina with accumulation 
of mucus secretions proximal to the obstacle. These secretions are secondary to 
intrauterine and postnatal stimulation of uterine and cervical glands by 
maternal estrogens. A triad of congenital HMC, polydactyly, and cardiac 
anomalies are the cardinal features of McKusick-Kaufman syndrome, which is also 
known as hydrometrocolpos-polydactyly syndrome. Bardet-Biedl syndrome is a 
well-known combination of hypogonadism, obesity, postaxial polydactyly, renal 
dysplasia, retinal degeneration, and mental impairment. In this case report, we 
describe a neonate with HMC, polydactyly, and hydronephrosis.