Cleft Lip Repair – Optimal Window: 3–6 Months of Age Unilateral cleft lip surgery is recommended once the infant reaches 3 months of age with satisfactory body weight. Bilateral cleft lip patients with slower physical development may delay surgery to 5–6 months. Surgical goals: Layered suturing of lip muscles and skin to close the lip cleft, with concurrent minor correction of collapsed alae nasi and asymmetric nostrils.