How does smoking affect fertility and pregnancy outcomes?

• A. Smoking reduces ovarian reserve, impairs oocyte quality, increases miscarriage risk, and worse obstetric outcomes.
• B. Smoking enhances ovarian reserve.
• C. Smoking has no effect on fertility.
• D. Smoking reduces the risk of miscarriage.

Answer: (A)

Smoking introduces toxins that harm both the ovarian reserve and the developing embryo. It accelerates depletion of the ovarian follicle pool, leading to a reduced ovarian reserve and potentially earlier loss of fertility. It also damages oocytes directly through oxidative stress and DNA injury, which can impair oocyte quality and raise the risk of chromosomal problems in embryos, contributing to miscarriages.

In pregnancy, the harmful chemicals cause vasoconstriction and poor placental perfusion, resulting in problems such as placental abnormalities, fetal growth restriction, preterm birth, and low birth weight. The overall picture is a clear pattern: smoking lowers fertility potential and worsens pregnancy outcomes, including miscarriage risk.

Other options suggesting any enhancement of ovarian reserve, no effect, or reduced miscarriage risk do not align with the well-established evidence of smoking’s broad negative impact on fertility and obstetric outcomes.